It carries the loads of sheer stress and cabin pressure. Figure. 9 shows the combined features mentioned above. The semi-monocoque structure is considered.
NASA-CR-19289I
,.-ii_/r,?v:i 7 •*' />
O
DEPARTMENT COLLEGE OLD
OF OF
DOMINION
NORFOLK,
©
SCIENCE
.
)
/
_.,
UNIVERSITY
VIRGINIA
GEOMETRIC
ct3
COMPUTER
SCIENCES 23529
MODELING
FOR
COMPUTER
AIDED
DESIGN
By James
L
Progress For the
Schwing,
Principal
Report period ended
Investigator
January
1, 1993
O tS_
Prepared National
o
for Aeronautics
Langley Hampton,
Research Virginia
and
Space
Administration
Center 23681-0001
" _I ,,, O" z
tn
u t"
,d"x 0", it", _0 l.r', +.,-4 0
,.-I ',0
©
62
t'_ ,_+D
Under Research Lawrence SSD-Vehicle
t April
1993
Grant
NCC1-99
F. Rowell, Analysis
Technical Branch
Monitor
.
DEPARTMENT COLLEGE OLD
OF COMPUTER
SCIENCE
OF SCIENCES
DOMINION
NORFOLK,
UNIVERSITY
VIRGINIA
GEOMETRIC
23529
MODELING
FOR
COMPUTER
By James
L. Schwing,
Progress For
the
period
ended
Aeronautics
Langley
and
Research
Hampton,
1, 1993
Grant
Lawrence
Submitted
Administration
23681-0001
NCCI-99
F. Rowell,
SSD-Vehicle
Space
Center
Virginia
Under Research
Analysis
Technical
Monitor
Branch
by the
Old Dominion P.O. Box 6369 Norfolk,
January
for
National
April
Investigator
Report
Prepared
V
Principal
Virginia
1993
University
Research
23508-0369
Foundation
AIDED
DESIGN
Geometric
Modeling
Progress
for Computer
Report
Aided
- January
Design
1993
1. Introduction
Over
the
past
implementation carried
several
software
out under
this grant
(VAB)
of NASA
resulted
in the
development
the
Research
interactive Tool
sonnel
of
puter
and
aided
the last
year,
execution
surface the
and
of the
the
and grant
The
Solid
among
these
Environment
it is the purpose
particularly
has
Aerospace
the
design
work
This
Modeling
by EASIE,
and
Analysis
Corp.
Primary
of smactural
parallel
to design
vehicles.
Vigyan
studies.
In addition, areas
grant
of the Vehicle
and
provided
implementation,
representation
investigators
design
tools
in the
members
Corp.
SMART,
of this
of aerospace
with
and
and Execution.
development
goal
design
Sciences
tool,
consultation
of the per-
and
in the areas
algorithm of com-
algorithms.
specifically
proposed
to consider
the
areas.
Provide general consulting codes; in particular, design Establish perform Research Build
and
Integration
geometric
primary
out jointly
packages
modeling
to provide
the
Computer
of several
software
design,
During following
grant
carried
Langley,
integration
Software
this
development,
the
been
in the conceptual
has been
geometric
and
for Application
it has
to be used
Branch
arel
years,
on the use and development of aerospace structural and implement a new Structures Module for SMART.
a database interface for POST that allows data consistency checks for the model. the possibility
a prototype
of providing
X-Window
interface
a general
data
for EASIE.
easier integrity
definition checker
of data for EASIE.
analysis and
helps
-2-
Develop transfer
methods for the creation of smoother, "faired" surfaces for SMART to allow the of SMART geometry to structural grid generation programs and other analysis
programs
requiring
Develop
algorithms
This report papers.
Copies
of this report ence
surfaces
articles
to a number
of the
Master's
they
appear
provides
ally provides
initial
user interface
that
paper
to otherwise
have
obtain.
and
computing.
presentations been
appended
The other
are therefore
and journal to the
papers
not included
and
end
confer-
here.
Codes
designers
property
makes
it easy
proven
to be of interest
with a rapid prototyping
analysis. to learn
it has become
tools
In addition, and use.
a priority
into the areas of aerodynamic
Recently,
a new design
concerned
engineering team
and
to number team
effort
have
phase.
tion plans
for the
gone
groups
the type
analysis.
at NASA,
with the purpose
through
has
a formal
These notably
collected
review
process.
extensions
to SMART.
of the
work
centered
on taking
the
The
personnel
structural
implementation on this grant
analysis
portion
plans aided
of the
and
approved
continuing
in the development
codes
including
analysis
that
the
HISAIR
requirements synthesized The
design
system on
have project. from
all
by
the
team
is
requirements
to the of the
consulting
is
analysis
enhancements
and
for these
first
engineered
of the SMART
documents here
a carefully
of soliciting
were
and addition-
of vehicle
the capabilities
and su'uctural
requirements
capability
design
and developing
debugging
The
SMART
Given
to extend
of other
was formed
groups.
since
completing
A major documents
conference
an AIAA
of Structural
mass
in VAB,
presently
and
and distributed
projects,
in the open literature
conceptual
support
design
requirements.
Extensions
SMART
conducted
of Master's
may be difficult
as cited
exacting
use of parallel
projects
2. Use and Development
2.1 SMART
more
for the efficient
refers
since
to meet
coding
and
implementa-
on the general
-3developmentof tion
of these
transfer
system
Corporation. developed
data
improvements
A portion
project
"Surface Generation Vehicle Fuselages", ence, 1992.
In addition, implementation This
has
several
included design
the primary
structure
includes
of
the
a lifting-body
task
between
needs
to be changed
following
James
interior
Computer
structure
por-
Sciences
for fuselages,
was
to support element
in the VAB.
has been
the development
involved
these
converting At present
of
been
focused
conceptual
design
and
level
a discrete
stage
wing
sections the vehicle
hardcopy
is changing
design.
and
in
of the priThe
model
multi-bubble with
and
involved
model
vehicle.
and internal
from
codes
element
launch
design
aerospace
analysis
of a finite
a two
on the
linear
tanks. and
the analytic
quamodel
changes.
and other
Robinson.
stage
has
structural Some
codes
and analysis
of the primary
results
have
been
provided
of this work,
resulted
through in the
publication.
"Structural tem", J.C. and
to meet
grant
underway
the sections.
on these
by Mr.
of finite
fuselage,
scaling
Consultation
tools
configuration
dratic
grant
design
this
first
of this model
this
under
air-breathing
Development
to develop
with
for the final
Consulting
aided
currently
to programmers
code
Operations Applied ato Structural Support of Aerospace ODU Master's Project, Department of Computer Sci-
the use of a number
studies
given
that used
research
of computer
Of these, mary
Analysis
continuing
been
of the actual
by Ms. S. Schwartz.
and Editing S. Schwartz,
Structural
Implementation
has
of this code,
as a Master's
2.2 General
algorithms.
and Loads Analysis of a Two-Stage Fully Reusable Advanced Launch SysRobinson and D.O. Stanley, Fourth Symposium on Multidisciplinary Analysis
Optimizations,
September
1992,
AIAA
paper
# AIAA-92-4774.
-4-
2.3 Smooth
Surfaces
Recently
there
has been
(CFD)
analysis
to models
which
generate
CFD
an increasing
interest
at the conceptual
grids
and provide
in applying
level.
the
computational
Currently,
corresponding
none
analysis,
fluid dynamics
of the
software
provide
tools
systems for model
generation. As while
a fast
reducing
uniform the
stage the
rational
basic
size
bicublc
building
smoothness
of this,
3.1 Database POST
for
Interface is an event
is batch
oriented
leads
to a high
degree
an ahernate
Current
the
method
be specified.
they
for futme
algorithms to given
exhibit
data
properties
surfaces.
the were
developed
sets.
NURB's
necessary
This work
smoothing
to find were
to carry
resulted
of data sets
out
in a Master's
has
non-
chosen the
as
desired
project
by
extension
driven
program,
the
taking
input
from
POST
data
has
prototype
and
these
to which
an ascii
techniques
favorable. to tabular
The
to the
personnel
variables,
set
above
categories.
flexibility
items.
For
of POST
example,
of input
when
parameters
of such input. prior
work
parameter on this grant
the
the
The
different
for the definition the
into
file.
of data
a completely
implemented
falls
'event'
in the definition
no tools
designed
applies
input
is selected,
provides
extremely
of the
B-Splines",
EASIE
of guidance
which
been
for Data Reduction using Cubic-Rational Department of Computer Science, 1992.
of interdependence
research
a prototype
reaction
approximations
investigated
to POST
POST
into
grant
In essence
of an Algorithm Master's Project,
Enhancements
must
data.
since
needed
on this
Macri.
"Implementation C. Macri, ODU 3.
the
B-spline
blocks
conditions
Ms. Carol
of
personnel
last
piece
of Schwing variables are
Grimm
of POST.
currently
necessary
and
engaged
for a phase
User in one
-5releaseof students,
a new
Ms.
Hima
on integrating data
entry
POST Gurla
data
EASIE
and Mr. Vasu
provides
design
systems
of the
ing the efficiency.
EASIE
that
driven
aspect ascii the
the Athena domain do
and
provides
some
mand
user
time,
and
form
out
carried
work
out by graduate
has also commenced
snipping
the
current
of the data
namelist
integrity
Tsai
and
and
seem
and
analysis
emphasized.
check-
that
in this
area
resulted
in two highly
the application
Ms. Ya-Chen
Kao
to the
public
derived
is rapidly
to
of the
is designed
system
for for
is in the public
becoming
of public
domain
available. software
interface.
master's
environment.
respectively.
tools
in technology
in this system
of the user
modes.
interface
is the windowing
combination
different
improv-
the importance
advances
advances
in two
and
of software
this user
X-terminals
this
Result-
codes.
of the software and
and execut-
codes.
errors
a collection
of recent
of these
analysis
reducing
Currently,
advantage
of X-servers
stand-alone,
released
Most
the task of building
programs
to the next revolution
can operate CCE
and
been
not take
it would
will lead
carried
design
X-Windows.
gazing,
EASIE
by Ms. Chia-Lin
does
simplify
between
On the forefront
in the
hardware
environment,
and
that
a methodology
has
has been
interface.
crystal
both
of EASIE
at MIT,
research since
one
terminals
and hardware
The
being
the application
of diverse,
of data
engineering
of EASIE
project
low-cost
divided
version
utilities
consisting
exchange
the task of coordinating
presenting
the database
will allow
a set of interactive
aided
for simple
At the same
with
This
is currently
EASIE
ing in a streamlining
menu
work
Bokka.
directly
of POST.
and
ing computer
Now
This
described.
3.2 X-Windows
To
interface.
management
requirements
ing previously
ease
user
projects.
These The
The
effort
are the complete work
was
was com-
completed
-6"User Interface Design Computer
Science,
"Application Department
4. Parallel
the
IRIS
They
a certain
amount
efficient
clear
machines
that much
and/or
Master's
for EASIE",
that
Y-C
Project,
Kao,
Department
of
ODU
Master's
Project,
in computing
power
will arise
personnel
of the
Further,
on this grant
standing
algorithm of application
Joe Rehder
of VAB.
have
in to support
machines.
While
adjustment
or distributed Algorithms
near optimally
principal
investigators
programs
will come
this can only been
on
areas
will
that work
occur
extremely
is contained
under of this
direct
this can be seen
VAB
machines advantage
and
can and
do provide
careful
grant
if the proper
the
single
next
utilization ground
in providing
of
processor
new
impact
on research
major
of parallel
work both
of exciting
in the following
environment,
conversion.
that
via the proper
design
investigation
for sequential
automated
in
analysis
of this
requires
developed
productive
a number have
these
to take
initially
Indeed, the
environment
anywhere
development
This
environments.
brought
algorithm
developed.
of analysis
processing.
been
parallel
may not perform
the development
have
improvements
computing
all multi-processor
of any
belief
of the future
distributed
of automatic
being
It is the
number
are
use
the algorithms
tributed
ODU
1992.
computers
programs.
true
Tsai,
Algorithms
use of parallel
new
C-L.
Driven Interface Generation of Computer Science, 1992.
It has become in the
for EASIE",
on
and
dis-
is developed. the basis
architectures being
impact
The
for under-
and
also
conducted
in a
by Mr.
publications.
Optimal Parallel Algorithms for Problems Modeled by a Family of Intervals, ( S. Olariu, J. Schwing and J. Zhang ), IEEE Transactions of Parallel and Distributed Systems, v.3 no. 3, (1992), 364 - 374. A preliminary version was published in Proc. 28-th Annual Allerton
Conf.
On the Power ( S. Olariu,
on Communication, of Two-Dimensional
J. Schwing
and J. Zhang
Control,
and Computing,
Processor ), Parallel
Arrays
Processing
Optimal Parallel Encoding and Decoding Algorithms and J. Zhang ), International Journal of Foundations
1990,
282-291.
with a Reconfigurable Letters,
1, (1992)
for Trees, ( S. Olariu, of Computer Science,
Bus System, 29-34. J. Schwing v. 3 no. 1,
7 (1992), 1 puter
- 10. A preliminary
Science
Conference,
version
of this paper
San Antonio,
Integer Problems on Reconfigurable and J. Zhang ), Journal of Computer
Texas,
J.
Channel Zhang
1991,
in Proc.
1991
ACM
Com-
I - 10.
Meshes, with Applications, and Software Engineering,
A preliminary version has appeared in Proceedings ence on Communications, Control, and Computing, A Constant-time J. Schwing and
appeared
March
( S. Olariu, J. Schwing accepted for publication.
of the 29th Annual 821-830, 1991.
Assignment Algorithm for Reconfigurable ), B/T, v. 32, (1992) 586 - 597.
Allerton
Meshes,
Confer-
( S. Olariu,
Fast Computer Vision Algorithms on Recortfigurable Meshes, ( S Olariu, J. Schwing and J. Zhang ), Image and Vision Computing Journal, v.10 no. 9, (1992) 610 - 616. A preliminary version of this work has appeared in Proceeding of the 6th International Parallel Processing Symposium, Beverly Hills, 1992. Selection
on Meshes
J. Schwing,
with
and J. Zhang
Multiple ), B/T,
Broadcasting,
accepted
( D. Bhagavathi,
P. Looges,
S. Olariu,
for publication.
Simulating Enhanced Meshes with Applications, ( R. Lin, S. Olariu, Zhang ), Parallel Processing Letters, accepted for publication.
J. Schwing,
and
J.
Applications of Reconfigurable Meshes to Constant-time Computations, ( S. Olariu, J. Schwing and J. Zhang ), Parallel Computing, accepted for publication. A preliminary version of this paper appeared as "Constant Time Integer Sorting on an nxn Reconfigurable Mesh" in Proc. of the International Phoenix Conf. on Computers and Communications, Scottsdale, Arizona, 1992, 480-484. A Simple Selection Algorithm Shen, L. Wilson, and J. Zhang lication. Parallel
A preliminary and Distributed
Fast Mid-level Vision J. Zhang ), Parallel EWPC'92, IOS Press,
version Systems,
for Reconfigurable Meshes, ( S. Olariu, J. Schwing, W. ), Parallel Algorithms and Applications, accepted for pubof this work appeared in Proc ISMM Pittsburgh, October 1992, 257 - 261.
Algorithms on Reconfigurable Computing: From Theory 1992, 188-191.
Meshes, to Sound
Sorting in O(1) time on a Reconfigurable Mesh of Size Schwing and J. Zhang ), Parallel Computing: From Theory ings of EWPC'92, Plenary Address, lOS Press, 1992, 16-27.
( S. Olariu, Practice,
Conference
on
J. Schwing Proceedings
and of
nxn, ( R. Lin, S.Olariu, J. to Sound Practice, Proceed-
A Fast Selection Algorithm on Meshes with Multiple Broadcasting, ( D. Bhagavathi, P. Looges, S. Olariu, J. Schwing, and J. Zhang ) Proc. International Conference on Parallel Processing, St. Charles, Illinois, 1992, p. 111-10 - III-17. Fast Component Labeling Zhang ), Computing and and Information, Toronto,
on Reconfigurable Information - Proc. 1992, 121 - 124.
Efficient Image Processing Algorithms Schwing and J. Zhang ), Proc. of Vision May 1992.
Meshes, ( S. Olariu, J. Schwing and J. International Conference on Computing
for Reconfigurable Meshes, Interface, 1992, Vancouver,
( S. British
Computing the Hough Transform on Reconfigurable Meshes, ( S. Olariu, J. Zhang ), Proc. of Vision Interface, 1992, Vancouver, British Columbia, Time-Optimal Sorting and Applications on nxn Enhanced Meshes, ( Schwing and J. Zhang ), Proc. IEEE lnternat. Conf. on Computer Systems Engineering, Comp Euro '92, The Hague, May 1992, 250 - 255.
Olariu, J. Columbia,
J. Schwing May 1992.
and
S. Olariu, J. and Software
-8Interval-RelatedProblems on Zhang
), Proc.
ASAP
Recontigurable
"92, Berkeley,
Efficient Image Computations Zhang ), Proc. of CONPAR
August
Meshes,
( S. Olariu,
1992, 445
on Reeoniigurable '92, Lyon, France,
Zhang
Polygon ), SPIE
Problems Conference
on
Meshes, September
Reeontigurable
on Vision
( S. Olariu, 1992.
Meshes,
Geometry,
Boston,
An Optimal Parallel vertex Cover Algorithm Schwing, W. Shen, and J. Zhang ), Proc ISCIS 1992, 49 - 55. Geometric J. Zhang
Problems ), Proc
ISCIS
on Meshes Conference,
with
Multiple
Antalya,
J. Sehwing
( S. Olariu, Geometry ( S. Olariu,
November
J.
and
J.
Broadcasting, November
J. Schwing Conference,
J. Sch'wing
and St. and
J.
1992.
for Cographs, ( R. Conference, Antalya,
Turkey,
and
- 455.
Convexity Problems on Meshes with Multiple Broadcasting, J. Zhang ), Proc. 4th Annual Canadian Computational John's, August 1992, 365 - 370. Convex
J. Schwing
Lin, S. Olariu, J. Turkey, November
( S. Olariu, 1992,
J. Schwing
41 - 47.
and
-9-
Appendix Master's
Project
Reports
and AIAA
Conference
Procedings
Surface Operations
Generation Applied
and Editing
to Structural
of Aerospace
Vehicle
Susan
Old
Dominion
Advisor:
work was supported
University
Dr.
Professor
under
of
for the degree of Science
James
1992
NASA grant
of
L. Schwing,
of Computer
April,
1This
Department
satisfaction
the requirements Master
Associate
Project to the
Science of
in partial
Project
Fuselages
K. Schwartz
A Master's submitted Computer
Support
NCC1-99.
Science
1
Abstract SMART, sisBranch
Solid Modeling Aerospace Research Tool, isthe Vehicle Analyof NASA
Langley Research Center's computer-aided design tool
used in aerospace vehicle design. Modeling of structuralcomponents SMART
using
includes the representation of the transverse or cross-wiseelements
of a vehicle'sfuselage,ringframes and bulkheads.
Ringframes
are placed
along a vehicle'sfuselage to provide structural support and maintain the shape of the fuselage. Bulkheads
are also used to maintain shape but are
placed at locations where substantialstructuralsupport is required. Given a Bdzier curve representation of a cross-sectionalcut through a vehicle'sfuselageand/or an interiortank, this project produces a frrst-guess Bd'zierpatch representationof a ringframe or bulkhead at the cross-sectional position. The grid produced islaterused in the structuralanalysisof the vehicle.The graphical display of the generated patches allows the user to edit patch control points in realtime. Constraintsconsidered in the patch generation include maintaining %quare-like_ patches and placement of longitudinal, or lengthwise along the fuselage,structuralelements calledlongerons.
Contents 1
Introduction
2
Capabilities
5 of SMART
Aircraft
4
Structural
3.1
Design
3.2
The
of Finite
4.1
Steps
in the Finite
4.2
Creating
6
Algorithms 6.1 6.2
the
9 ......................
Design
Overview
Geometric
7
Design
Considerations
Actual
5
6
9
........................
Element
Analysis
Element
Mesh
11 15
Method
...............
18
........................
18
Representation
21
for Generating
Capabilities New Results
Bulkheads
Developed for SMART ............................
6.2.I
Bulkheads
6.2.2
Ringframes
and Prior
26
PAng&ames
to the Project
....
26 30
.........................
30
........................
36
Conclusion
Appendix the
37 A:
SMART
Implementation
of the
Algorithms:
Snapshots
Display
of 39
Appendix
B: Software
Requirements
Appendix
C: SMART
Code
for
to Implement
SMART Algorithms
Structures
65 103
List
of Figures
1
The Layout of the SMART
2
Ringframe from an offsetcurve [REHDER,
3
Bulkhead between fuselage and internaltank [REHDER,
4
Semimonocoque
5
Typical semi-monocoque
6
Typical transport fuselagecenter sectionfloor ment.
Screen [SMART,
construction [MCKIN,
p. 2-I] ...... p. 3] ........ p. 4]
p. 144] .........
stiffenedsheU--L-1011
8 9 12
[NIU, p. 376]
13
arrange-
beams
[NIU, p. 396] ........................
14
7
Typical pressure fiatbulkhead [NIU, p. 398] ..........
8
Fail-sa/edesign by using longitudinalbeam
9
lage. [NIU,p. 391] ......................... Sketch of main detailsof aeroplane structure [STIN66, p. 205]
10
7
14
along side of fuse15 16
Finitedifferenceand finiteelement discretizations of a turbine blade profile.(a) Typical finitedifferencemodel. (b) Typical finiteelement model. [HUEB,
11
An
arbitrary shape
p. 5] ...............
divided into nodes and elements.
17 The
shape is governed by the partialdifferential equation shown. The
value of this equation at any point in an element is a
function of the values of the nodes _i bounding
the element.
12
[BARAN, p. 3] . ......................... Model reduction due to structure symmetry ..........
19 20
13
Two
22
14
Bdzier curves and their control points [FOLEY,
p. 488] i The Bdzier curve defined by the points Pi is divided at t = into a leftcurve defined by the points Li and a right curve defined by the points P_. [FOLEY,
p. 508] ...........
15
Bicubic Bdzier Patch
16
Vectors and points used to calculatea patch
17
A fuselagecross-section ......................
18
25
.......................
A fuselage cross-sectionwith component
26
..........
29 42
cubic Bdzier curve
segments and control points.................... 19
A simple component
20 21
tank
cross-section
cubic
Bdzier
(simple curve
implies
segments
convex and
segments
and
control
points
2
................
shape)
control
A fuselage cross-section with interior simple tank A multi-bubble tank cross-section with component curve
43 with
points...
44
cross-section. cubic Bdzier
45 46
22 23
A fuselagecross-sectionwith interiormulti-bubble tank crosssection................................
47
A fuselage cross-sectionwith generated interiorcirculartank with cubic B_zier curve segments showing the path of growth for bulkhead patches................
24
. .......
with first-guessbulkhead patches................. 25
48
A fuselage cross-sectionwith generated interiorcirculartank 49
A fuselage cross-sectionwith generated interiorcirculartank with control points (plotted as one-third points) edited to smoother patches..........................
26
bulkhead 27
patches
A fuselage
patches
A fuselage and where
29
original
of near-equal
Initial
bulkhead
A fuselage section
editing
cubic Blue
locations
where
complish
equal
sponding
curves
Initial
of arclength
bulkhead
simple
with
Bdzier squares
on the
original number
given
of near-equal patches
based
between fuselage cross-section section ................................ 33
Bulkhead fuselage
34
after
editing
cross-section
Placement of twelve interior multi-bubble
53 growth
of patches
on cubic and
55 cross-
correspond-
cross-sections were
indicate split and
of arclength Bdzier
54
between ....... tank
between
per cross-section,
percents
curves
cross-section.
multi-bubble
cross-sections
of control and
corresponding
cross-section
green
of curves
to accomplish
points
curves
points.
............ Bdzier
52
locations
tank
interior
.....
cross-section
simple tank
growth
split and
on cubic
of control and
cross-section
and
ing points.
32
percents
cross-section
tank
51
first-guess
curves
indicate
were
cross-section,
and
with
curves.
corresponding
per
cross-section
after
simple
cross-sections
based
growth
growth
between
cross-sections
patches
fuselage
fuselage 31
given
tank
inward
interior
green
inward
interior
curves
of curves
curves
Bulkhead
with
the
B_ier
on linear
growth
on
number
between 30
without
based
Bdzier
squares
equal
on cubic
cross-section
cubic
Blue
based
cross-section
bulkhead 28
50
A fuselage cross-section without interiortank with first-guess
corre-
.......
growth
multi-bubble
to ac56 curves
tank
cross57
points
multi-bubble
of patches tank
between
cross-section.
longerons on fuselage cross-section tank cross-section .............
58 with 59
35
Placement terior
36
Placement interior
37
tank
of thirty simple
A fuselage A fuselage
tank
cross-section percent
on fuselage
cross-section
of thirteen
constant 39
longerons
tank
simple
Placement interior
38
of nine
simple
longerons
on fuselage .................
longerons
with
in. .
cross-section
on fuselage
cross-section along
cross-section
cubic
with constant
61 cross-section
patches B_ier width
60
with with
.................
with ringframe
of growth
cross-section
cross-section
................
62 generated curve ringframe
with
segments. patches.
63 64
1
Introduction
"A model is a representation of some (not necessarilyall)featuresof a concrete or abstract entity. The
purpose of a model or an entity is to allow
people to visualizeand understand the structure or behavior of the entity, and to provide a convenient vehiclefor'experimentation'with and prediction of the effectsof inputs or changes to the model [FOLEY, many
instances,the model is the only means
pp. 286-7]." In
in which analysis can be per-
formed to determine feasibility of an idea. Costs of creatingan actual entity or the testingfacilityfor a particularentitymay be prohibitiveand a model provides the simulation of the entityforexperimentation and learning about a proposed system. The
cost of memory
and computing
the past two decades and made
time has decreased drasticallyin
the computer
one of the most viable tools
for modeling. In particular,graphics-based modeling tools are now used "to createand editthe model, to obtain values foritsparameters, and to visualize itsbehavior and structure [FOLEY,
p. 287]."
In the mid 1970's, the Vehicle Analysis Branch, VAB, ley Research Center, LaRC, system. Numerous
of NASA
began development of itsown
Lang-
solid modeling
commercially produced systems were evaluated and de-
termined not to meet the needs of the VAB.
Thus, SMART,
or Solid Modeling
Aerospace Research Tool, was begun in the 1980's to provide the VAB
with
itsown computer-aided design tool foraerospace vehicledesign. A primary method
of modeling used by aerospace and structural engi-
neers is based on the abilityto create a "nice" grid on a surface. Finite element analysisand computational fluiddynamics both relyon known
val-
ues at points relativelyclose to one another to predict values of quantities likestuctural stressat other points. Currently, the difficulties in producing suitablegrids for these analyses slows the design process. Manual
means of
producing the grids are unsuitable and automating the process is the desired method. The
goal of this project has been to automate the B_zier patch gener-
ation of fuselage bulkheads and ringframes used in the structural analysis of aerospace vehicles. Sections two through fiveof this paper provide insight into the basicsof SMART,
aircraftstructuraldesign, the finiteelement
analysisprocess,and the geometric representationsused in the modeling process. Section six presents the algorithms developed to generate the desired 5
patches. Snapshotsof the SMART display the algorithms are provided as Appendix tures requirements document
showing the implementation of
A.
Copies of the SMART
and source code are prodded
struc-
as Appendices
B
and C, respectively.
2
Capabilities
SMART,
of SMART
written in the C programming
language, was developed for use on
the Silicon Graphics IRIS workstation, a computer graphics
hardware and the UNIX
which features custom
operating system.
The initialmodeling
requirements of the software included: • ability
to generate
complex
vehicle
shapes
easy
manipulation
component
grouping
• facilitate chial • provide
data
analysis
display, small
shown
input
facilitated
to create are
with
extensive represented
components
using
representation
of
a hierar-
to
a variety
of
slider
p.
main
bars
from over
for
"Bdzier
viewing
the
mouse and
primitive
and
shapes cubic
given
curves
evolution.
over
the
pressing
or a series
a
desired
Most menu,
an appropriate that
is, SMART-
or by
"free-hand"
SMART
cross-section 3]."
of the
for displaying
In particular, p.
oc-
or viewports,
shapes,
modifying
[MCMIL,
features
an area
components,
viewport.
"novice,
main
windows and
to the
of vehicle the
The
viewport
basic
creating
arbitrary
2]."
pertinent
in the
to accomodate
menus,
by positioning figure
p. 1].
designed
two large
mouse
by either
was
[MCMIL,
1, are
generation
capability
completely
user
[MCMIL,
be created the
vehicle
geometric
horizontal
and
automatic
rendering an
two
geometric
may
descriptions
easily;
users
is accomplished
Objects
geometric
scheme;
with the
in Figure
bar, or plotted button.
and
of the
of SMART
area,
of menus
quickly
a single
experienced
textport
a variety user
interface
and
3-dimensional
and
interaction
user
casional,
from
programs;
• real-time The
accurate
The
"has
capability cross-sections
of points
connected
® SMART
"'
FILl[
"
@
NASA/L,_C_JSSD/VAB
I"'""1 C|
'_ I
S'U_aCI[
CVTS
t'-'
P_Y._$1M
I'-'*"'f ''_' I'""_'l CmLCIM.AIOR
Mira;ION
*"*
CFO SRIOS
Mk",,.P
®
®
Prima IROTAIP£1_NIWlNOIZ,_U
OPTIONS
®
v
|OOL|AH
MAIN
IZ-_MIDU.Y
I _lOC_qCl
•
_I}"K_
l
_.'wJ!
_RI
ROiI,,II_:_NIW_fll
Z..ZH I 1.2Hl
I
m(:Ii[
I111;I
OOe(IORT),II
_(_/"
®
Figure 2-1 The Layout of the SMART
E. Mode Menubar
A. Textport B. Clock C. Function
F. View Windows Name Area
D. Information
Figure
Screen
G. View Option Menubars
Display Area
1: The
Layout
of the
H. Menu Display Area
SMART
Screen
[SMART,
p.
2-1]
_t"U
Figure
by straight
2: Ringframe
lines,
discussion Once
of processes.
dation
of the
ment
requirements.
paper,
for the
pp.
3-4]
component
have
of the
the
cross-sections the
currently
and pp.
portion
and
applied
require-
represents
generation provided
and document.
to constructing
the
creating
arate
curve
the
cross-section
representing
The
planar
in several
as in Figure
surface,
different
represented
types
of files.
as in Figure
of a tank
interior
placeB of this
model
curve,
a bulkhead,
fulfill-
[REHDER,
from
a ringframe,
the
longeron
in Appendix
requirements
for a
New
analysis.
offset creating
A
consoli-
is generated between two curves: surface of the fuselage; the other
fuselage
3]."
is the
components. A planar surface curves is formed by the outer the
p.
is accessed
developed,
this project
24-28],
of the
technique
[MCMIL,
component
being
bulkhead
p. 3]
5 of this paper.
for structural
written
See [SOFT,
pertinent
describes
been
[REHDER,
in Section
process
ring'frame
curve
is created,
generation
specifications of many
is presented
A capability,
model
ment
an offset
to as Cartesian
curves
a geometric
variety ments
referred
of Bdzier
from
of these
one of the is a scaled 2, or a sep-
to the
fuselage,
3. by Bdzier In particular,
bicubic
patches,
SMART
has
may the
be stored capability
of writing an ASCII text file of the patch data for an entire vehicle in the format known as a "neutral file." This file may then be "read" by the PATRAN
structural
analysis
program
[PATRAN]
and
this
geometry
is used
as
f Figure
3: Bulkhead
between
to create
a suitable
a template on that
grid
for various
3
Aircraft
3.1
Design
The
design
namics the
of the ture. each
and to the
[STIN66,
payload,
air. fuel,
the various
the
airframe
engines.
perform
[REHDER,
finite
p. 4]
element
analysis
loadings.
is great
design
engineer.
of the This
and
must
the
the
often attitude
190]." 9
run
the
distribution predicting
and
air-loads
a sound these
thousandsw
weight
to the
such as the
of the
engineer throughout
sur-
airframe
loads
within,
is to produce
into
of the
shaped
distribute
structural
aerodyconsiders
reaction
the items
job
the
aerodynarnicist
in accurately
surface,
of both
of specially
must
an accurate
difficulty
of speed,
The analyzes
also protect
engineer's
cases--which
efforts
"envelope
envelope
Given
structure's
combined
shape
structural
combinations p.
stress
the
structural
190]."
The
there
on
critical
then
tank
Design
requires
presence
the
Because point
[STIN66,
the
p.
and
vehicle,
"most
and
as an aerodynamic
surrounding
and
internal
Considerations
air
surfaces
and
Structural
engineer
rounding
grid
pressure
of an aircraft
vehicle
fuselage
strucloads
considers arising
at the
from
the flight
_Structural control,
design
the operational
[STIN66,
p. 192]."
each deserves scope
affects
and
which
at high
• The study in which
of loads the
or bearing, cross-sectional stress. shape defined
and
Shear
are
shear. element.
stress
as the
types
apply
to tensile
it should
ratio,
stiffness.
concern
and
both
the way
it is applied
in a particular
must
way, it is said
tensile,
to the surface.
compressive
caused noted
The
it is stressed.
that
strain
stress.
stress.
stress
material's
Shear
by shear
and compressive
be
in 1-g
is caused by tension across a stress is the reverse of tensile
when
displacement
explanation:
strength-to-weight
of stress:
tangential changes
angular
simplistic approach, strain causes stress.
three
the
on the ground.
the area over which is loaded
Tensile stress Compressive
occurs
multidimensionally definitions
and
and
and smooth
high specific
is of major
a material
There
vehicle
a high
design
are beyond
a cursory
wrinkle-free
and
on a material
When
stressed.
have
temperatures,
load is applied
be considered.
at most,
and
of an aeroplane
for structural
an unloaded
must
stability
full explanations
reasonably
from
envelope, potential
considerations However,
remain
material
flight
development
each win be given
is different
fabrication
to be
the
are many
skin must
particularly
strain
role and
There
paper,
• The outer
• The
achievable
to be fully explored.
of this
flight,
the
causes
is
Similar
Although strain
a and
Heat is also a consideration. The boundary layer of air surrounding a high-speed aircraftbecomes heated and raisesthe temperature of the skin of the aircraft.External radiant heat may also be a factor. The elasticity/plasticity of a material is an important factor. If the strain caused by a stresscompletely disappears when
the stressis re-
moved, the material is said to be wholly elastic.If the strainhas not disappeared, the material issaid to have a permanent
"set" and plas-
ticityhas occurred. "A structure is designed so that the working range of any component
does not exceed itselasticlimit. It is now possi-
ble to study stress-patternsestablished in structural components various states
applied that
proportional
loads ....
within to the
elastic stress
A useful limits
general
law, known
of a material
producing I0
it [STIN66,
the
as Hooke's strain
p. 197]."
produced
by Law, is
• Bending
and torsion or twisting must also be accounted for. Bending
takes place when
a load is applied to a point on the flexuralaxis of
a structural member and the reaction is at another point on the axis. Torsion will also occur ifthe reaction is offsetfrom the flexuralaxis. • Fatigue
is also
studied.
It occurs
lower than maximum structural members. None
tensile
when
stress
repeated
stresses,
allowable,
cause
each
the
much
cracking
of
of these items can be taken in isolationand generally combinations
axe considered simultaneously. "An important aid in structural analysisis the Principleof Superposition: that the totalstraincaused by a load-system may be considered as the sum of the individual strainscaused by the various load components, taken in isolation[STIN66, p. 197]." "The analysis of stress and strain in advanced aircraftstructures has forced the development of very elegant and complicated mathematical niques. The dynamic
structural engineer must
tech-
relate the effectsof weights, aero-
inputs, elasticresponses and stress distributionsthroughout
the
structure as one whole, for a wide variety of differentshapes. Fortunately, the grid-likeconstruction allows accurate analyses to be made into mathematical
and translated
statements that can be handled by computers
[STIN66,
p. 213]."
3.2
The
The
airplane
This
paper
Actual has
Design three
will only
basic
address
parts, the
the
fuselage,
the
parts
of which
fuselage,
wings, are
and
the
the
focus
tail. for
this project. "The airplane cargo,
controls,
capacity a spacecraft
seen
is the
axe attached
airplane.
the
fuselage
and
and
and
It should
body
other have
which items,
the
aerodynamic or missile
to which
wings
provides
space
depending
upon
smallest qualities
may
the
streamline of the
be called
but
4 and
5 .
This
means
11
that
the
tail
crew,
the
and
size
consistent
... The is more
body or tank [MCKIN, p. 140]." The modern aircraft's fuselage is of a semi-monocoque in Figures
the
for the form
airplane
a fuselage
and
fuselage
main
unit
of an
passengers, design with
of the desired
structure
commonly
called
construction, has
of
a framework
as
Figure 4: Semimonocoqueconstruction which
supports
placed
on the fuselage.
elements. called
The
lage's
frames,
longitudinal
little
doors
in Figure
plates
serves
of the
at the frames
than
that
This
of the
but
are
paper The
helps
6.
to distribute may
are used
of the
to maintain
types
support
over
areas
to the fuseat
the skin
for doorways
the structural
are
is a substantially
is placed
the loads
stresses
of structural
perpendicular
A bulkhead
be cut-out
of the
fuselage
A bulkhead
a fuselage,
144]
most
of several
or rings•
across
as in Figure
primarily
cross-section
loads frame
consists elements
formers
There
withstand
p.
points
of
and
allows
and
holes,
requirement,
as seen
7.
A frame outline
and
and
expansion. and
must
framework
cutting
beam,
loads,
radial
which
or transverse
cross-section
concentrated
skin
The
vertical
bulkheads,
constructed
but
an external
[MCKIN,
are
ported
by the
bulging
due
smaller and
and
are used
components
bulkheads
to severe
and stresses.
shape
which
or rings
of the
body
can be seen
construction
Formers
to all of these
longitudinal
the
of the vehicle,
bulkheads.
lighter
refers
to maintain
and
in Figure
of the frames have
to maintain
the same
a uniform
has
can
8. The
be lighter
outline
shape
the
as the
of the
skin.
as ringframes. are longerons
frames They
and also 12
and
support are
used
stringers. the
They
are sup-
outer
skin
to prevent
to carry
the
axial
loads
Figure 5: Typical semi-monocoquestiffened shell--L-1011 [NIU, p.
13
376]
lhaN
r-tm_
Figure
6: Typical
transport
fuselage
center
section
floor
beams
arrangement.
[NIU, p. 396]
!!
Figure
7: Typical
pressure
flat
14
bulkhead
[NIU,
p. 398]
Longitudinil_
Ii.
_','_"
_
. =,=,,
__
8: Fail-safe
[NIU,p.
\
"_C'_'C/
Poor _lm
by using
longitudinal
beam
along
by bending.
and
Longerons
aft of the
vehicle
are
and
especially
run
the
designed
length
to take
of the
and of lighter construction. See Figure 5. external skin is formed from metal sheets which
frames
and
stress and above. The
bulkheads cabin
a high
4
pressure.
and
to weight locations.
total
failure
Overview
Finite 1]'.
Figure
element
Originally
9 shows
ratio,
and
It has
design
through
load
is defined
the
it is well
suited and
redistribution
to be a "group
equations
developed
for the
of any study
15
loads
Stringers
are to the
loads
features
to be "very
Element
governing
the
combined
flexibility
end
are attached
It carries
is considered
of Finite
analysis the
or welding.
structure
strength
without
approximating p.
by riveting
semi-monocoque
combinations failure
of fuselage.
the
fuselage.
shorter The
has
side
391]
caused fore
design
I I _-.;7
_r I.
Figure
._./3.
of sheer
mentioned
efficient,
i.e., it
for unusual
can withstand [NIU,
load local
p. 377]."
Analysis of numerical
continuous
of stresses
methods
system in complex
for
[BARAN, airframe
'Ruddavain_- combinedelevsLof Tailplmes famed dthol ss bqr| D-oosedtelsina I_uts I by sepillte Iti_ and spas
_lefms andflapssimi_ to
__
Crasharchattached to lawwd bulkheadand box bwa keel Suplxxtsporta_,.tst=bo_d |lazed petal-lype canopydoocs
"
Lar|e box-beamkeel fastenedto main luselafe hzme,suppeflsseals, ho_ses
spazs,born _d IroeLfuselage box-bern. Rent framesupportsenginemounting
rellact_blenosewheelat forw_d end. controlr_s androds andtakes
Figure
9: Sketch
andluddeg:telJJs8 edle sj with r|bletsmd skimordishedskin to replace s41blllslq r&inls.
of main
"
Separateribs andsparset torsionbox with I_nose leadingedgelairin|.
__
details
of aeroplane
16
structure
•
(STIN66,
p. 205}
Figure 10: Finite differenceand finite element discretizations of a turbine blade profile. (a) Typical finite differencemodel. (b) Typical finite element model. [HUEB, p. 5] structures [HUEB, p. variety
of engineering
complex
costs
and scientists. of this method. The values
The
model. and
This
process
of creating
to the
tire problem. determine
in Figure
elements The the
then
size and
accuaracy
at selected model
connected, and
the
original
nodes
of the
combined
of the
elements assumptions model.
to represent
of elements
analysis.
17
and
a suf-
system
is
of the
discretization made are
a solution simplifying
struc-
governing
elements
equations,
Solutions
many
with
physical
are
users
of the
is called
differential
engineers
the
the
and
infinitely
points
of the define
to
frequent
point
is to approximate
nodes
number
is the
analysis
when
all
most
at each
with
restricted
to virtually the
in a
in hardware
or structure
10. Simplifying from
specified and
evaluated
was
declines
remain
used
for problems
analysis
or structure
A mathematical
or nodes,
functions,
applied
individual
element
points
is illustrated
being
system
of accuracy.
The
available
engineers
is also
effective
process
system
today
element significant
this
quantity of the
finite
but the
aerospace
of finite
equation
approximating then
unknown
degree
created.
made and
method
It is particularly
of a continuous
objective
differential ficient
have
element
recently,
computers,
Civil
difficulty of the
ture.
Until
mainframe
processing
finite
disciplines.
geometries.
expensive
3], the
to create which
are
created
for
for the
en-
assumptions
4.1
Steps
in
Finite
element
which
has
the
Finite
analysis
its own
Element
Method
Can be performed
difficulties
and
time
in a sequence
of five steps,
requirements.
They
are
each
of
summarized
as follows: .
Perform ments
the
discretization.
is the most
accuracy
of the analysis.
on the nature next section. 2. Define erties .
Dividing
important
boundary
elethe
take various
This is discussed
conditions
in nature
analytical
into affect
or loading
polynomial
The
may
structure
this will greatly
of each element
interpolation
them.
the physical because
properties
Formulate tiating
Elements
of the problem.
the geometric and
phase
equations because
of the
expression
in greater
and
ease
in the
any material
prop-
to the
element. in these
for the displacement
at any
analysis.
These
in integrating
functions
depending detail
pertinent
for each
interpolation
shapes
are
and
differen-
equations point
often
give
inside
"an
the ele-
ment" [BARAN, p. 4]. The value of the equation at any point in an element is a function of the nodes bounding the element. See Figure 11.
.
Assemble Step
.
the system
2 above,
Make additional equations
may
and
equations,
solve
calculations, be used
accounting
if necessary.
to calculate
structural analysis, nodal values values are then used to calculate
4.2
Creating
the
There
are two basic
spring
elements
variety
of engineering than
plate than
the
outlined
in
other
The solution
of the system
of
parameters.
For example,
in
represent body displacements. These strains and stresses in the elements.
Mesh
categories
are examples
greater
for properties
the equations.
problems
cross-sectional
or shell elements. The their other dimensions
of planar
elements:
of line elements. to represent depth
line and
Beam parts
or width.
area.
elements whose
Area
are
lengths
elements
plate elements have a thickness and are usually represented by
18
Beam used are
in a much
include much three
and
flat
smaller or four
Y7 a2_
_z_
.I
j Figure
11:
An arbitrary
is governed
by the
equation
at any
point
nodes.
or volume
The being
model
structure placing
being likely
this
that
it is a "waste
that
of the
by the
the
location
shape
of time
and
element
of the
corners
and
of the
accounting
actual
pattern
the
Other
of nodes
p.
The
size
on and
19
structure
regions
mesh
meshes John
having
of the
is created,
can be created
M.Biggs
precision
element
model
locations
model
symmetry,
the
as saying
greater
than
88]."
significant The
structure.
choice
Finer
to account
physical
A coarse
quotes
of the finite
a coordinate system with an origin definition of nodes and elements. Ultimately,
nodes
dimensions.
problem,
methods
[HUEB,
structure's
shape of this
of the
used
of the actual
physical
Huebner
discontinuities.
for the
value
values
of element
are determined.
to employ
nodes.
The
The
to other
and load points.
analysis
elements.
of the
compared
the
if necessary.
of the
and shown.
type
is an idealization
support,
mesh,
input
shape
structure by
initial
The
are a third
to be stressed
at stress,
from
equation
is significant
created
nodes
p. 3]
By understanding
most nodes
elements
x
is a function
[BARAN,
thickness
analyzed.
into
differential
element.
whose
divided
in an element
the
Solid
shape
partial
• ; bounding
for parts
/
should
of the
of nodes closely
model
can
as in Figure
an axis elements
is determined
12.
of symmetry depends
be
reduced
Establishing allows
on
include
approximate
the
easier type
of
I
I
I I
•
I _axm
Figure 12: Model
finite
element
suggests
analysis
being
the following If the
using
analysis
• Nodes
should
where
to transition should
from
be made
When
using
plate
ferred
shape
because
elements
should
stresses
and
or discontinuity
points,
as displacements should
a series
they
in the
99]. _ analysis.
other
locations is required.
If it is necessary
dimensions
a factor
elements,
are more only
the
only
p.
of two.
of adjacent The
transition
of elements.
or axisymmetric be used
than
should
"localized
displacement
if possible.
to fine meshes,
disconti-
strains
and
94-99]:
mesh
or temperatures,
be used,
by more
pp.
that
[HUEB,
load
differ
across
states
at supports,
coarse
not
This
Huebner
geometric a refined
than
spacing
should
principle. cause
[HUEB,
and/or
requiring
mesh
such
required.
modeling
a more refined
be placed
mesh
elements
Venant's
accuracy
loads
and areas
of the load
information,
Uniform
concentrated
St.
requires
the
element
discontinuities
vicinity
• Stress
and
for finite
dimensions
or geometric
immediate
performed
involves
minimum
be determined loads
reduction due to structuresymmetry
as rules
problem
nuities,
of symnmtryJ
when
transitions.
2O
accurate required
quadrilaterals than
triangles.
by the
are
the pre-
Triangular
geometry
or for
•
The
aspect,
ements
or length-to-width,
should
be as close
as 5.0 are permissible, • In triangular angles
and
should
all angles ations
but below
quadrilateral
be used.
are
60 degrees,
surfaces
all in one should
should
plane.
be less than
• Poisson's in the
ratio,
material
optimum
or right
el-
as large
obtuse
angles
in the
or acute
triangle,
quadrilateral,
where
but
devi-
with flat elements by the
whose
surface
nodes
and
the
are
plane
15 degrees. be less than
of an applied
contracts
no extreme!y
is the equilateral
subtended
An
elastic
while
direction.
in the tension
Poisson's
0.5.
tension
to the tension
to the tension.
ratios
is permissible.
angle
should
direction
perpendicular
or quadrilateral Aspect
3.0 is preferrable.
be modeled
The
of triangular
as possible.
elements,
The
of up to 30 degrees
• Curved
ratio
to unity
elongates
its cross-section
During
direction
material
and
simple
contracts
compression,
expands
the
perpendicularly
ratio is the ratio of the resultant
perpendicular
strains to the parallel strains. Most metallic materials have a value of 0.25-0.3 and an assumed value of 0.3 is used. It is also assumed that Poisson's material
ratio approaches [NILES,
• Lengths
and
of zero
may
areas
nodes
It is assumed ness.
5 Vehicles shape
the
of the
smaller
elements
for the
twisting
model's
fiat
must
be non-zero.
Values
results.
elements
fiat plate
Geometric are drawn
area
not extend across to cause numerical
that
If in-plane
represent
and
unpredictable
and
reach a maximum
151-152].
of line
produce
Elements should ness. This tends ditional
pp.
0.5 as the stresses
discontinuities or changes in thickerrors and inaccurate results. Adshould
elements
is allowed,
have plate
be used. no in-plane elements
rotational do not
stiff-
accurately
plates.
Representation using
vehicle•
curves There
and are
surfaces
numerous
21
which ways
approximate
the
desired
to represent
such
curves
D
It /
/
•
/
•
'_.
r
p,
Figure 13: Two
Bdzier curves and their control points [FOLEY,
p. 488]
and surfaces. As surface representations are a generMization of curve representation, this section will firstconsider working with curves. Often, a parameterization of curves,where each coordinate, z, _/,and z, isa function of a parameter, t, i.e.,z -- z(t),I/= _l(t),z= z(t), is used to avoid problems occuring with explicitand implicitequations used to describegeometric figures.For specifics, see [FOLEY,
p. 478].
The predominant method used in SMART
isthe B_zier form of the para-
metric cubic polynomial curve segment. This consistsof 4 points, Po, /'I, P2, and P3 where P0 and P3 are endpoints of the curve segment and PI and P2 are additional controlpoints. Generally not on the curve segment, points JD1
and P_ indirectlyspecify the tangent vectors to the curve at P0 and P3.
Specifically, the directionof the tangent vector at Po is determined by PoP2 and the directionof the tangent vector at P3 is determined by P3P2.
See
Figure 13. To determine a point P on the curve segment, the parameterization of the domain The
is set up so that
weighting
factors
at parameter
for each
t -- 0, P -
point,
known
are:
Boa(t) B,_(t) B_(t) B_(t)
= = = =
22
Po, and
as the
(i - t)_ 3t(1 - t)_ 3t_(1-t) t3
at t = 1, P = P3.
Bernstein
polynomials,
The resultant equation to evaluate P is:
e(t) = Z Pj× B](t) j----O
Note
that
of cubic 2-D;
P(t)
is guaranteed
polynomials.
z, !/, and There
to be cubic
The
sum
in t because
is computed
it is a linear
for each
combination
coordinate,
z and
y in
z in 3-D).
are
several
advantages
inherent
to this
Cubic curves do not "wiggle" as much
representation:
as higher order polynomials and
give a relativelysmooth approximation of the desired shape. Note that a cubic curve is the lowest degree polynomial to interpolate to four requirements: the two endpoints and the specifiedderivativesat each endpoint [FOLEY]. • The
resultant curve segment
is contained by the convex hull of its
representativepoints. This guarantees that the curve segment isplanar. Calculation
of the
notably the
at the
linear
The
endpoints,
combination
storage
points
derivative
is easy. of the
requirements
and
possibly,
at any
point
For a given
derivatives
for a curve
information
on the
curve
t, P'(t)
of the
are
slope
continuity
most
is calculated
Bernstein
segment
about
segment,
as
polynomials.
minimal--the with
four adjoining
segments. Another
way
of pairs
of the
resentation
to compute given
four
to inherit
the
P(t)
involves
points.
formation
is applied
generation,
or if the curve
transformation. be applied computation
to the
four
linear allows
four
these
23
from
viewing
points
time.
points,
interpolations the
invariance.
scaling, rotation, result is the same
is generated
control
linearity
of a_ne
original
Therefore, to the
This
property
applying an affine transformation, lation, to a Bdzier curve, the
successive
Bdzier
That
shearing, whether
followed
the points,
of the segment,
or transthe trans-
by the followed
transformations which
rep-
is, when
need
curve by the only
minimizes
To represent end.
a given
Continuity
shape,
of segments
successive
is guaranteed
the next curve. If slope continuity then P_ and P3 of the first curve remain
coUinear.
Sometimes eter
Moving
a B_zier
t is normally
place would
curve should
be split.
be exactly
the original
[FAR.IN,
is the piece
pp.
technique
75-77]
on the curve
and
HRs.
and
gives
The the
point point
L4 (which Q(t)
t. The
Ra, R2, Rs,
four
center
four
s:
where are
ratio the
and
x
of distances
curve,
or the
of the curve [0, c] and the
pp. 507-510]
the geometric by drawing
and
construction
As in Figure
slopes
the
L3R2
value
a point
X
of the
patch.
collinearity points points
second
14, "the
point
the construction
form
P(s,
must
same
Bdzier
points
ratio
curve
at
for the first
Bdzier
bicubic
patches
in a 4 x 4 gridlike
a Bdzier
curve
pattern.
segment.
The parameterization
t) is calculated
The requires
by:
Poo Pol ?o2 ?o.s Po6 Po8 Po9 P1o P. P. Pl4 for the Bernstein Slope
points
on either
be consistent
24
t2 t 1
between
point
side of the
_3
polynomials
continuity
of a control
on either
control
by the
of the
tttt3 L2H
curve.
positioned
patch
of the surface.
matrix
between
control
divides
to surfaces.
points,
of the
MB
by maintaining
boundary
control
coefficient
control
RI)
p. 508],"
R.t are for the
t, and
points
the
using
of t is found
can be extended
control
1 ]
is the
the
interval
La, L2, La, and L4 are the control
and
a side
s and
control
achieved them
s
MB
the
on
points
two variables,
sz
points
by sixteen
points
If the param-
the first piece
in 1959.
is also
[FOLEY,
representation
are determined
value
endpoint(s).
of t in this interval
c along
to [c, 1]. [FOLEY,
this process
is required, curve must
it divides P1P2 and P2P3 in the ratio of t : (1 - t), divides P2Pa and PaP4 and L3R_ to likewise divide
curve
B_zier
a value
In essence,
by F. de Casteljau
parameter and
[0,1],
end-to-
is set to P0 of
at the
curve over the parameter's
for a parameter
line L2H so that so that it similarly
the slope
percentage
corresponding
describe
developed
if P3 of one curve
over the interval
the
curve
are placed
to be split into two pieces.
a certain
second
The
curve needs
to represent
where
curves
from one segment to the next and Po and P1 of the second
P2 or P1 "controls"
defined
can be specified
B_zier
is
between
Additionally,
side of the the
the P;'s
two patches
on the border
border.
along
and
boundary
edge.
the and
Calculation
L2_'
L3
= [I 4
4
at t = x into by the points
Figure 14: The B_zier curve defined by the points P/is divided a left curve defined by the points Li and a right curve defined /_.
[FOLEY,
of the with
p. 508]
slope
at a given
respect
point
to parameters
All surfaces
in SMART
sometimes
two other
ever,
is equivalent
to the
representation the
B_zier
endpoints
curve
curve in this
curves
for clarity
The tangent utilizes There
in editing
multiple,
representation
vectors
to each
matrices which
which are
is the
endpoint and the allow
included
is the
one-third
of t = 0,½,§,
and
are the spaced
B_zier
method.
Often
vectors
conversion
in Appendix
25
The from
The
on
that
the
one-third
directly
on the
curves. the
Hermite
slopes
of the
representation
to represent one
point
points
Note
same.
other
two tangent
1.
how-
of which
of the
points
closely known.
patches; each
first
"control-like"
are easy
bicubic
values
to place
derivatives
are used,
coordinate
representations
project
B_zier
The
the
values
for both
the two endpoints
the other,
with
using
by partial
15.
for curves
representation.
Hermite
are
t. See Figure
are represented
at parameter
used
are
is achieved
representations
requires
of the
points
s and/or
B_zier
which
on a patch
the curve.
representation
C in the matrices2.h
file.
to
14
11
75
12
3
o
Figure
6
Algorithms
15: Bicubic
for
B_zier
Patch
Generating
Bulkheads
and
Ringframes 6.1 As
Capabilities Project with
many
redrawn
graphics
at speeds
has remained
Developed programs,
which
routine
and
based
on its present
coordinates,
the
mouse
over a menu,
a bar,
while
of the
The
This main
loop
performed.
The
time
(true)
exit else
main
if over
a main-menu
option
loop and
redisplay;
a menu
checks
then
begin 26
then
is constantly
the
mouse
the
user
the
by explicit
of SMART
the
accomplished
is:
image with
location
had
Based
or editing
through
to the
that
on the screen.
loop is exited
loop in this portion
begin if choosing
screen
whether
are accomplished each
Prior
believing
is generally
or over a viewport
is refreshed
main
on the
eye into
determines
calculations
display
being
structure
software.
certain
The
of the function The
in the
position,
are available.
image
human
on the screen.
a looping
mouse's
the
fool the
continuously
for SMART
placed on the
capabilities
loop, menu
regardless choices.
if
over
main-cross-section-menu
exit
main
loop and
then
redisplay;
else if over store-patches-menu store else
patches
if over
in SMART
data
type.of.growth.menu
redisplay else
then
patches
if over
using
structure
B_zier
or linear
growth-direction-menu
redisplay
with patches
and
redisplay;"
then i_orrnat;
then
interior
or exterior
to cross-
section; else
if over store
new-edge-menu
partial
then
patches,
leading
edge,
begin
and
new calculations
from
old
redisplay;
end else
if over
a bar
then
begin if over
patch-growing-bar
calculate
partial
then
patches
redisplay; if over radius-bar
else
calculate else
new
given
redisplay; if over centerline-bar
then
and
percentage
and
then
patches
calculate else
to given
new patches
given
new
radius
length
new
centerpoint
and
position
redisplay;
if over
ringframe-bar
calculate
new
with
then
patches
ringframe
for ring'frame
value
and
redisplay
patches;
end
else
if over edit
the
control
right-view'port points
and
then redisplay;
end The fuselage symmetry
initial
algorithms
cross-section of the
for creating
represented
cross-section
bulkhead
by a linked about
a vertical
27
patches
list of Bdzier axis
centered
on a given
curves.
Due
to the
of symmetry,
the
cross-
section
representation
is actually
Figure
12. For the remainder
imply the "half-cross-section" Because many interior spherical
in shape,
of a tank, on the tank
axis
to the
created
fuselage of the
of the
a first-guess
cross-section,
with
cross-section.
around
the semicircle
one-third
The centerpoint
semicircular
points
of the
of the semicircle
on the fuselage cross-section. external to the cross-section by aerodynamicists The patches
will
cross-section
endpoints The
between
on the
points
on the
to correspond
to the
curves
of the at the
fuselage
calculated
and the default to any one-thlrd
The analogous representation has also been developed and may
for computational
generated
its
was placed
midpoint between fuselage cross-section endpoints, was half the minimum distance from the centerpoint
used
as in
to a cross-section
fuselage
were generated
of arclength
cross-section.
reference
cross-section,
unless explicit indication to the contrary. tanks of a vehicle are spherical or multi-bubble
of symmetry
cross-section
percent
of this paper,
the software
interior
one half of the complete
radius point
using a circle potentially be
fluid dynamics.
the given
cross-section
and
the semi-circle
represented a structural bulkhead between the fuselageand the tank. The percent-of-arclengthguide for generating tank points enabled the patches to have reasonable wedge-like shape, which is as close to square-likepatches as possible. The originalalgorithm was as follows: procedure begin for
bulkhead-first-guess
each curve
(cross-section,
in cross-section
centerpt,
radius)
do
begin calculate
1/3
calculate
inward
calculate
normalized
of each
pts on curve;
1/3
pointing
normal
vectors
from
vectors centerpt
1/3
pt;
in direction
point;
calculate tank-points at length radius direction of normalized vectors; comment:
to each
The
from
centerpt
in
two points and two vectors comprise
the Hermite representationof the curve, as seen in Figure 16.
28
C_laterpomt
Figure
I6:
Vectors
calculate 1/3
B_ier
and
B_zier
patch
points
curves
points
calculate place
and
used
to calculate
between
a patch
corresponding
tank-points;
patch
on linked
from
4 B6zier
curves
list;
end end Using ated
established
to enable
radius
the
of the
at most decrease
only
to move
is tangent
to the
or B6zier
Editing Because
fuselage
points
a position
patch points
on the
the
axis growth
Menus
is important
to allow
were generated
29
the
tank
fuselage until are
menus
is used
radius
bar allows
between
and
the
The
of symmetry
cross-section.
tank
until
in the
Another
bars A bar
growth
cross-section.
a bulkhead.
along
curve
of control the
fuselage
graphical
parameters.
allowing
to represent
and
semi-circle linear
routines,
to change tank,
to the
to zero tank
user
interior
tangent
interior
SMART
the the used
were
cre-
to change
the
cross-section is also
where
allowed there
centerpoint tank
is to
is no of the
cross-section
to allow
choice
of
cross-sections. smoothing according
of patch
wedges.
to a given
radius,
these
points
termining circle.
can be _dragged" the
change
Movement
and one-third Patch
is restricted
points
corner
with
the mouse
in arclength
to tank-points
on either
points
around
and recalculating
side
of the
which corner
on the axis of symmetry
the
the
semicircle
actual
are patch
point
are
on the
"corner"
are then
required
by de-
point
points
recalculated.
to remain
on the
axis.
The
eight
"dragged"
patch
with
control
points
the mouse
not
to smooth
on either
the
cross-section
interior
shape
may
also
of the patches.
be The
change in mouse position is used to calculate the new one-third point position. Points on the fuselage may not be edited in order to preserve the previously Due
determined
to the
speed
redisplayed
6.2
shape
based
of the
Silicon
on aerodynamic Graphics
and
structural
processor,
constraints.
changes
in patches
are
in real time.
New
Results
The specifictasking of this project was to allow automatic generation of a bulkhead or rin_ra.me for a given cross-section(s).The bulkhead would be drawn between
two given cross-sections,one representing the fuselage and
the other representing the interiortank.
This allows the interiortank to
have any predetermined shape and not be limited to being circular. The ring[tame would be drawn interiorto the fuselagecross-sectionat a default width which could be edited.
6.2.1
Bulkheads
There
were
head
between
patches
several the
problems
two cross-sections.
supports
the
current
sponding curve points that both cross-sections ments. may lems
Even not
if the
pair
were
of successive when
differences
Locations
number with
curves where
The
method
in creating
patches
requirement
of calculating
for
to have each
the
on each
in arclength splits
are
of curves to create following
is the
was
"nicely"
shaped which
greater are
their
algorithm
cross-section, made
same,
patch
using
splitting than
internally
3O
These
into
a predetermined stored
and
corre-
arclengths
compared curves
bulk-
problem is curve seg-
respective patches.
the
"square-like"
of the two cross-sections. The most obvious may not have the same number of B_zier
up in a fashion
solved
to consider
prob-
arclengths two
curves
percentage. create
an
addi-
tionalediting capability,explained in further detailbelow. The algorithm is as follows: procedure
match-curve-arclengths (faselage-cross-section, tank-cross-sectio
n)
begin calculatepercent of arclength of each curve in fuselage-cross-section; calculate
percent
of axclength
of each
curve
in
tank-cross-section; determine are look
value close
curves
there
and
curve
percents
of arclength
enough;
at first
while
where
in each
is another
another
curve
cross-section;
curve
in the fuselage-cross-section
in the
tank-cross-section
do
begin if difference curves
in percents
close-enough-value begin split
curve first
look
of arclength
in each cross-section
than
then
with larger
curve
of current
is greater
percent
will have
at second
curve
same
of split
of arclength
(pal):
pal as smaller curve
(other
curve; piece
of larger curve, farther along the cross-section) and the next curve on the other cross-section; end else look at the
next
curves
on both
cross-sections;
end end This the
same
algorithm number
accomplishes of Bdzier
percents of arclength, information is stored
curves
two things: and
both
corresponding
cross-sections curves
end have
up with
near-equal
within an agreed-upon factor. As mentioned above, as to which curve endpoints were created by splitting 31
originalcurves. Although
the percent of arclength is a reasonable way to
lineup corresponding curves, it is sometimes preferrableto move
the curve
endpoints to straightenthe patch wedges. "New n endpoints can be "dragged" with the mouse:
the change in mouse position is translated into the change
in percent of arclength of the split in the originalcurve and the original curve is resplitwith the new percent. The subdivision of a Bd'ziercurve is accomplished by finding control points of the curve as represented by a higher degree polynomial.
Each piece of the curve willrepresent the same
cubic polynomial on itsown intervaldomain, as explained in Section 5 of this paper on Bdzier curves or [FARIN,
pp.
75-6]. Therefore, each new
curve is an exact duplicate of the corresponding piece of the originalcurve. By returning to the originalcurve each time, the originalshape of the crosssection is preserved, but editing of at least some of the curve endpoints is now also a feature of the software. The other problem that needed consideration was the placement of Iongerons in the longitudinalstructuraldesign. The places where these longerons intersectthe fuselage cross-sectionneeded to be at "coruer" points of the patches for laterstructural analysis,as explained in sections3 and 4 of this paper on aerospace vehiclestructure and finiteelement analysis. The shape of the vehiclein many
instancesreflectsonly aerodynamic requirements, and
curve endpoints in the fuselagecross-sectionare usually not in the locations of longeron placement. The guidance from engineers at NASA cleAnalysis Branch can be summarized:
Langley Research Center's Vehilongerons are ideallyspaced equally
around the fuselage,but must especiallybe placed at discontinuity points, or curve endpoints where successive curves are not slope continuous with one another. Thus, a percentage of the longerons to be placed on the crosssection,equal to the percent of arclength of the portion of the cross-section between discontinuitypoints, should be equally spaced between the discontinuity points. If the desired placement of the longeron is too close to an already might
existing be created.
curve-length, percent between The
curve
endpoint,
To resolve
from
the
of the equal
curve
spacing
discontinuities, resulting
tion of a comparison
value
this,
narrow
if a desired
endpoint,
could
is shown
in two
to determine So_
which
longeron
for that
longeron
used
patch,
corresponding
curve-length
the
algorithm
a very
is undesirable,
position
is within
to less than section
be placed
of the
twenty-five cross-section
at the endpoint.
parts.
The
if the
placement
first
is the of the
computalongeron
a
requires curve
the splitting
of an existing
curve or if it will be placed
on an existing
endpoint: procedure
compute-compare-value
push-up-length, comment: and
back-up-length,
Because not
longerons
exactly
at the
push-up-length, positioning back-up-length, and
length-not-yet-included) may
located
past
located
previous
yet,
keep
position the
curves
track of the
term
of differences
in the
curve
of the
in section
compare-value
curve-length total
fuselage
total
to equal-spacing-length
calculated
longeron.
in the following
of the
end of equal-spacing-length,
or the
previously-placed
quantities
of the
difference the
did not
"section"
endpoints
end of equal-spacing-length,
which
the current portion discontinuities.
begin if first
the
before
the
difference
or the curve-length point
at curve
equal-spacing-length,
length-not-yet-included,
from
be placed
or the curve-length point
positioning
(equal-spacing-length,
and The
algorithms
axtual
use of refers
cross-section
to
between
then
= equal-spacing-length;
else begin if push-up-length
and
compare-value else else
if longeron
on previous
algorithm
= compare-value
for placing
push-up-length;
longerons 33
+ back-up-length;
curve -
end actual
then
> 0 then
end
The
-
= equal-spacing-length
not placed
compare-value
zero
> 0 then = equal-spacing-length
if back-up-length compare-value
are both
= equal-spacing-length;
if push-up-length compare-value
back-up-length
is:
then
length-not-yet-placed;
procedure
place-longerons(f_selage-cross-section, number-longerons-to.place)
comment:
The first
endpoint
of the
cross-section,
beginning further
along
the
of a curve
is the one
the second
closest
endpoint
to the
is
cross-section.
begin for each
section
of fuselage-cross-section
between
discontinuities
begin number.longerons-for-section
=
( number-longerons-to-place) if number-longerons-for-section
x (pal-of-section);
> 0 then
begin calculate
equal-spacing-length;
comment:
equal-spacing-length
= pal-of-section
by (number-longerons-for-section look
at first
while
divided
+ 1)
curve of section;
all longerons
not placed
in section
do
begin compute-compare-value; if pal-current-curve
= compare-value
then
begin place look
longeron at next
at second curve
endpoint
of curve;
in section;
end
else
if pal-current-curve
begin if not first longeron
curve was
34
> compare-value of section not placed
then
and on previous
curve
and
do
compare-value
< 25% of equal-spacing-length
begin place
]ongeron
back-up-length
at first endpoint
of curve;
= compare-value;
end else
if pal-current-curve differ
and
compare-value
by > 25% of equal-spacing-length
then
begin split
current
place look
curve
(wrt
longeron
at split
at curve
beginning
compare-value); point; at split
point;
end
else
if pal-current-curve differ
and
compare-value
by < 25% of equal-spacing-length
then
begin place
longeron
at second
push-ahead-length pal-current-curve •look at next
endpoint
= difference
curve
and
of curve;
of
compare-value;
in section;
end end
else
(pal-current-current
< compare-value)
begin increase
length-not-_let-included
by pal-current-curve;
look
at next
curve
in section;
end end place
longeron
at last
end end end
35
endpoint
of section;
then
This algorithm would be applied to the fuselage cross-sectionprior to the match-curve-azclengths algorithm to ensure that the interiortank crosssection matches the fuselagecross-sectionfor which the longerons have been considered.
6.2.2
Ringframes
The originalalgorithms enabled constant percentage ringfxames, i.e.,those ringfraxneswhose width at each one-third point of the fuselage cross-section •was a given percentage of the length of the Bdgier curve from the one-third point to the corresponding tank cross-sectionpoint,to be created. However, in actual aerospace vehicledesign, the requirement forringframes isconstant width and not constant percentage, although constant width is a misnomer. At points of discontinuity, the width of the ringframe isusually a littlewider, the leading edge of the ringframe maintaining the basic shape of the crosssection at a place of greater structuralstress. To create a realistic width for the ringframe at points of discontinuity,the followingalgorithm was used to change the calculated "normal" to the crosssection at 1:hediscontinuitypoint. When normal vectors to each one-third point are calculated,because the tangent to each curve at the discontinuity is different,the curves would have a differentnormal vector emanating
from
the same point. This algorithm provides an alternativeto just averaging the two norrnals at the discontinuitypoint: procedure
normal-at-discontinuity
begin for
each
discontinuity
point
do
begin calculate first calculate
normal
vector
to second
endpoint
curve meeting at discontinuity; normal vector to first endpoint
second compute normal
curve points
meeting
of of
at discontinuity;
corresponding
to tails
of two
vectors;
compute
tangent
compute
intersection
vectors
to each
point
36
curve
between
at discontinuity;
two lines
through
respectivepoints at vectors
the head
in the direction
new-normal
of the normal
of the tangent
-- vector
from
are then
constructed
vectors;
discontinuity
to intersection
end end The
ringframe
patches
procedure
as follows:
ring.frame.patches
begin for
each curve
in fuselage-cross-
section
do
begin calculate
4 inward
B_zier
representation section length
point
place
patch
point
in direction
, two vectors
in direction patch
using
of one-third
curve,
ring frame-width calculate
curves
Hermite on fuselage-cross.
of normal
at
of ringframe-width
of normal;
from
4 curves;
in linked
list;
end end
7
Conclusion
The
algorithms
sections mentioned tation
described
engineers
will be placed Actual
are provided The
in Appendix
complex,
may and
the
a user
needs
represent the
has been
being
of the
A of this
SMART
in the
feedback
from
positive.
The
developed display
current the
cross-
previously
final implemen-
structures showing
portion
these
results
paper.
can
be a very
to specify
a simple
implemented
extremely
the currently
of the user
reverse
been
preliminary
of software
Getting
reflect
cations
within
and
"snapshots"
development
evolution.
have
of SMART
NASA
of SMART.
truly
just
portion
long
and
sometimes
his or her requirements
can
be extremely
concept
is also often
37
yet true.
such
frustrating.
the implementation This
project
has
difficult that
they
The
specifi-
may
be very
added
a new
dimesion sign phases more
to SMART of aerospace
expediently
and should vehicle
enable
the
designing
research
and
development
in the future.
38
and testing
of the de-
to be accomplished
MASTER
PROJECT
Generating The Complete Control Environment Inferface for EASIE
by Chia-Lin
Tsai
Project Advisor: Dr. James L. Schwing Associate Professor of CS
Computer Science Department Old Dominion University Norfolk, VA 23529 April
1992
ABSTRACT
The
Znvironment
_xecution, design of
of utility
mode
quickly
the
of
supports
a central two
provides
data,
provides
depth
control
these
modes
and
a full of as
the
rapid
EASIE
of
sufficient
menu
action
items,
executing
guidance and
execute
Executive allowing
Users
can
This
project
will
this
project
are
and
a menu-driven
with
interface
is and
database,
(ADE),
process.
results
integration
modes
Control
and
conceptual the
users
executive
needed.
of
relational
Complete
design
needs
programs.
basic
select
programs,
_ntegration
integrating
analysis
which
with
which
review
which
(CCE), users
switch
consider
in-
between the
CCE
interface. Two
selecting
will
task
about
users
application
the
face
the
meet
Application-DerivedExecutive
execution
mode
to
programs
provides
_oftware
designed
engineering
of programs
operations:
to
that
stand-alone
execution it
was
engineers
many
a set
EASIE,
for_pplication
objectives menus
selecting be
by
of using
structures
implemented
in the
a windowing of
the
selecting
X window
ii
system
system,
to and
redesign to
menus. OSF/Motif
the
reorganize The
project version.
CONTENTS
PAGE
ii
ABBTI_CT CONTENTS LIST 1
2
OF
iii FIGURES
iv
AN INTRODUCTION TO THE F_BIE 1.1 Why EASIE was developed 1.2 What EASIE was 1.3 What two operation modes 1.4 What CCE mode was A COMPARISON BETWEEN THE AND THE DESIGN PRINCIPLES 2.1 Be consistent 2.2 Provide feedback 2.3 2.4 2.5 2.6 TWO 3.1 3.2
BYBTEM
of
EASIE
1 I 1 2 2
were
CURRENT EASIE SYSTEM ..........................
Minimize error possibilities Provide error recovery Accommodate multiple skill Minimize memorization OBJECTIVES Redesign Reorganize
................
3 3 4 4 4 5 5
levels
OF THIS PROJECT ..................... the selecting menus the selecting structures
6 6 8
4
AN OUTLINE OF THIS PROJECT ......................... 4.1 A general view 4.2 Improvements 4.3 A sample session using the CCE mode 4.4 A command summary using the CCE mode
10 10 12 13 17
5
CONCLUSION
21
.........................................
REFERENCES APPENDIX
A:
State-transition
APPENDIX
B:
User
APPENDIX
C:
Sample
APPENDIX
D:
manual
Programs
screens and
diagrams of
this using
files
iii
of
this
project
project the of
CCE
this
mode project
of
this
project
LIST OF FIGURES
PAGE
Figure
1
WorkSpace
2.
Basic
Control
Environment
menu
9
e.ooo,oooo_eeoooo..oooooo
easie.input
File,
iv
............
11
1.
AN INTRODUCTION
1.1
WHY
E_IE
The
_nvironment
Execution, design of
that
stand-alone
need
for
Research
Center's
WHAT EASIE
uniform
task
meet
and
the
of
_ntegration
needs
tools
the
results
stemmed
activities
Division
and
conceptual
programs has
engineering Systems
of
integrating
analysis and
access
to
The the
solution to
the
_oftware
with
[REF
9].
from
the
Langley
(SSD).
WAS
uses
techniques
the
most
iterative
through
programs
predominant One
quick,
data.
design
progresses
application
refined
a
system
technique.
successive
increasingly
via
of
EASIE
to
analysis
facilitates
process. In
supports central in
application automatic program a
face
interface.
final
aid
to
Space
provides
methodology
this
designed
techniques
design
EABIE
l_pplication
engineering
such
aided
1.2
for was
engineers
computer
a
DEVELOPED
EASIE,
many
The
_
OF THE EASIE SYSTEM
design.
addition, rapid
EASIE integration
relational the
is
and
of
programs,
EASIE the
and and
a
of
utility
execution
review
EASIE
provides
1
of steps both
which about
utilities
tasks:
coordination of
programs
provides
and
logging
programs
of
following
modification
definition
Therefore,
set
database.
execution
execution
a
data executed a
which
selection of
program files
of data, during
throughout
methodology
a
and
set
of
software
coordinating
1.3
TWO
OPERATION
The
guidance
items,
execute
full
design
are
sequence allows
the
results these the
1.4
modes
WHAT
CCE
MODE
CCE-mode
operating
system
can line.
be
This
of
data,
users
user
second which
using
project
will
of
provides
a
a
and
can
of
techniques design
sequence.
iteratively Users
action
control
CCE,
the
with
mode
establish
re-execute input
menu
in-depth
to
(ADE),
users
select The
when
executing
review
switch
consider
This the
between
redesigning
interface.
The
multitude
the
of
provides
(CCE),
interaction.
as needed.
task
codes.
modes
programs.
automatically
minimum
CCE-mode
review
example,
refine
the
Executive
which
Executive
allow
to
basic
allowing
For
engineer
with
quickly
interface
then
analysis
two
mode
Control
which
and
with
application
process.
provided
and
ease
_pplication-_erived
to
Complete
executive
the
first,
to
EASIE
execution
sufficient
execution,
OF
users
menu-driven
and
design
MODES
provides
operations. a
programs
engineering
EASIE
is
utility
of issued Various
WAS interface without
files, via
provides requiring
directories, menu
levels
or
selections of
menus,
available.
2
or
the
flexibility
the
user
data. typed
display,
to
In
CCE,
in
via
and
of
help
an
track
a
commands a
command text
are
2.
A COMPARISON
BETWEEN
AND THE DESIGN
To
design
number
of
human
error
2.1
factors
above
model,
of
the
have
been
portion
help
fully
is
to
error
recovery,
memorization.
in
[REF
8]. significant
in
let the
good
feedback,
buried
problems,
a
ensure
provides
utility
consider
provide
minimize
EASIE
respect
interface
menu
position at
a
within
logically
us
the
current
consider
EASIE
each
interface.
and
commands
such
can as
consistent.
fixed
be
used
Help,
always
menu,
and when
characters whenever
Status,
conceptual
hardware in
binding
the
output
displayed
in
the
same
is
being
Cancel
can
portion same
messages
are
codings
are
the have
input
the
input, be
in
the
considering always
text and
3
The
system-status
place,
addition,
keyboard
and
example,
are the
In
EASIE,
function
For
items
employed. of
is
sequencing,
uniform.
the
relative
always
EASIE
functionality,
EASIE,
shown
more
these
with
and
to
CONSISTENT
First,
EASIE
levels,
this
see
to
provide
discussed
however, To
BE
are
have
consistent,
above,
interface. the
be
skill
described
we
which
possibilities,
are
functionality;
interface,
design:
multiple
As
of
a
principles
user
human
principles
in
accommodate These
good
design
minimize
EASIF. SYSTEM
PRINCIPLF
a
factors
THE CURRENT
same global
invoked
ab
any
time,
are
provided
EASIE
and
generic and
can
PROVIDE
FEEDBACK
Feedback
can
corresponding
as
Hove,
to
any
type
applied
EASIE
be
to
functional
of
interface
sequencing
is
Copy, of
and
Delete
object
in
example,
user
when
2.3
MINIMIZE
an
Users of
The
system
the
the
Cancel, provides
thus
EASIE
provides
some
word
of
provide
is
the
accepted
functional
input by
the
feedback,
communicated
to
the
processing.
input
tries
to
there
may
Correct. Cancel
not
input,
etc.)
acknowledgement
errors
interface
important
the
each
the
POSSIBILITIES
ERROR
and
when
and
Currently,
keyboard
object,
does no
to
levels,
sequencing,
satisfied. as
is
make
user
PROVIDE is
is
ERROR
how,
It
EASIE
operation
will
job
matter
such
there
possible
design.
restricted
position,
However,
three
hardware-binding,
is trivially
(command,
system.
at
user-interface
feedback
language
given
the
levels
hardware-binding
2.4
be
such
system.
2.2
for
commands
to
minimize be
some
in any
minimize the
system, error
errors
error
as
occurred
and
it
is the
possibilities. possible. in
the
No
future.
RECOVERY to
provide
error
Unfortunately, feature.
recovery: EASIE
Undo, currently
Abort, only
2.5
ACCOMMODATE User
interface
accommodate help,
multiple
not
skill
some
not
does
which
the
about
how
a
interface
use
commands.
to
extensibility
which
functionality
to
combinations
new
does
users
productive options, going
2.6
EASIE
final
principle
memorization.
on
facility. full
user
a add
primitive additional
new
commands the
which to
down
For
explanation
offer
and
used
these
EASIE
can
allow
start
with
specialized
as
doing
specifying commands,
or
procedures.
MEMORIZATION
system
commands
interface
hiding
bogged
start-up
EASIE
Finally,
commands
infrequently
the
defining
complexity
becoming
complicated
MINIMIZE
by
basic
without
learning
The
not
work
through
minimize
learn
but
a
commands.
provide
next,
give
the
provides
do
does
letting
interface
interaction it
help
not
EASIE
existing
not
to
detailed
means
the
of
interface
Thirdly,
does
however,
faster
to
help
prompts,
Secondly,
what
sufficiently
to
EASIE,
are
ones.
suggest
EASIE
used
accelerators,
which
sufficient.
offer
example,
to
be
complexity.
slower
is
can are
hiding
replace
generally
not
which
accelerators
that
prompts
LEVELS
levels
and
provide
techniques
SKILL
methods
extensibility,
does
are
MULTIPLE
seems a
of The
to
complicated
be
user
interface
original
redundant. menu
to
economic.
5
configuration A
get
design
new
what
user is
is
to
of has
needed.
to
the read It
is
3.
TWO OBJECTIVES
There
are
selecting the
menus
3.1
using
of
a
structures
this
project:
windowing
redesign
system,
according
to
the
and
the
reorganize
design
principles
above.
REDESIGN
THE
Redesign
of
(CCE)
mode
OSF/M0tif
SELECTING the
will
be
skill
to
_omplete
the
in
the
initial
This
EASIE
X
we allow hide
_xecutive
window
menus
will
system:
_ontrol
the
selection,
windows.
in
the
implemented
numerical
be
level
of
Since
with
menus
MENUS
menus
version.
alphabetical those
objectives
by
selecting
outlined
of
two
OF THIS PROJF.,C'T
system,
of
CCE
want
to
the
mode
are
redesign
accommodation
complexity
from
have
a
the
user. Window-based feature
of
expect
all
user
most
computer
The of
software
X
user
that
the
to
display
hardware recompiling,
window
X
supports or
relinking
are
the
protocol application.
6
beginning
to
Massachusetts
industry-standard to
portable
and
common
user-friendly at
an
addition, text
X
are
programmers
In
the
become
polished
is
that
containing
users
developed
allows
protocol.
windows that
have
(MIT),
interfaces
7]
and
System,
that
sophisticated supports
to
Technology
system
[REF
systems,
applications
interfaces. Institute
interfaces
to
X
allows
develop any
programs
graphics without X
system
on
any
modifying,. is
based
on
a
network-transparent and
manipulates
and
sends
a
that The
toolkit
provides manager
is
description
visual
manager reducing
Third, the provides
of
windows
to
windows
on
describes
the
standard
behavior.
It
writers
with with
is
for
icons,
a
guidelines guidelines
the
on moving
restoring workspace. for
guide
to for
for
style
2]
is
First, of
applications. upon
OSF/Motif
files
works
that
with
from
Finally,
the
usage,
providing
the
toolkit
The
window
windows, icons, style
and
and guide
toolkit
application
widgets, widgets,
and
interface
resizing
windows
new
the
describe
of
screen.
and
toolkit
which
developers
states
the
The
presentation
manager
designing
styles.
collection
window
using
many
particular
guide.
varied
text
manager
windows
functions
arranging
writers
window
in
presentation
interface
initial
and
[REF
toolkit,
and
simple
and
operation
any
application
create
changes X
system
OSF/Motif
allows
or
interface
window
the
clients,
device-independent
of
and
rich
Second,
The
define
a
creates
from
input
a
manager, a
based.
to
X
graphical
properties
components.
the
server
between
not
combining
standard
designers
user
a variety
building
language
interface
of
is for
a
of
X
requests
provides
for
window
gadgets
to
does
also
interface
The
different
X
a base
toolkit
and
manage
X
language,
widgets
to
that
version
user
OSF/Motif
response
important
style. as
mode.
clients
is
OSF/Motif
description
the
notify One
serves
graphical
window
in
systems
interface
layer
the
to
state.
window
user
a
windows
events
window's
other
client-server
widget and
window
manager
writers
customized
window
provide
the
behavior
3.2
with
standard They
Menu,
Data
Menu,
Procedure
are
find
of
example. there
ACTIVATE, easier
are
or
elements
user
interface
then those
be
the
"Permanent"
and
of
the
in
to
selection
only
six
They
decisions. be
more
choose
take 1 on
have
READ
and
FROM
UFD.
they
need.
In
8
page.
read
for
all
the
we
want
to
us
have
an
WORKSPACE,
REMOVE
what
of
difficult
Let
DESCRIPTION,
the
example
Therefore,
the
and be
next
to
efficient.
mentioned
will an
is
Menu,
redundant
the
It
concerning
choices:
TEMPLATE, to
choices.
their
Execution
Menu be
of
Control
Building
to
us
seven Menu
Workspace
reorganization
Figure
choices.
menus
are
Let
shown
your
users
ones
has
Application
Procedure
the
design
a "Permanent"
Menu,
objective
make
interface
Menu,
Menu,
old
their
to
of
mentioned
EASIE
Selection
twenty-eight
SAVE for
the
the
Menu
select
If
will
of
previously
memorization.
Control
reorganize
four
reorganization
addition
Utility
that
minimization
selections,
of in
Menu,
One
to
the
Execution
ineffective.
There
the
Review/Modification
We
Workspace
standard
is
1.0
menus
Building
above.
these
new
STRUCTURES
to
Version
Template
a
SELECTING
respect
principles.
commands.
be
objective
with
different
designing
Together,
to
THE
second
interface
for
applications.
REORGANIZE
users
managers.
OSF/Motif
for
The
guidelines
then
NEW, It
COPY,
will
addition,
be the"
user
can
if
not
he/she
paths. the
does There
file
WORKSPACE 1 2 3 4 5 6 7 8 9 i0 11
- READ - CLEAR - TYPE -NEW - COPY
12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
-
ENTER
enter
name
not is or
no
some
commands
know
or
way
path
for he/she
make the
with sure user
file about
to
get
name
or
the the
file
with names
information
needs.
CONTROL DESCRIPTION
LOG
OF
WORKSPACE CONFIGURATION TEMPLATE APPL. PROG. PROCEDURE INFORMATION COMMAND LOG PROCEDURE WORKSPACE CONFIGURATION WORKSPACE
OLD
PROCEDURE ACTIVATE WORKSPACE CONFIGURATION TEMPLATE APPL. PROG. UTILITY INPUT TEMPL OUTPUT TEMPL PROCEDURE PROGRAM UFD SAVE TEMPORARY WORKSPACE PROCEDURE REMOVE FROM UFD WORKSPACE CONFIGURATION TEMPLATE PROCEDURE SET USER LOGIN CHARACTERISTICS
COMMAND RD WS RD CFG RD TPL RD APPL RD PROC CL T¥ LOG TY PROC N WS N CFG
CP WS CP PROC ACT WS ACT CFG
ACT ACT
TPL APPL
ACT ACT ACT ACT
UTL ITPL OTPL PROC
ACT PUFD SAWS SA PROC RM WS RM CFG RM TPL RM PROC SLOG
COMMAND: Figure
I.
WorkSpace
9
Control
FORMAT
menu
path or of
4. AN
4.1
OF TttlS PROJECt
AG__ The
main
existing
purpose
EASIE
selection a
processing
EASIE
command
checking
for
front
menu
are
system,
menu
provide
but
end
to
be
into
EASIE
passes
where
processor,
and
they they
messages
are
of
users
warnings
will
window is
which
handles
basic
necessary
end.
to
also
the
EASIE
window
for
be
the
error
commands
user
the
to
to
and
EASIE
in
the
the
project
easie.file
ln
change
processing
front
shown
to
this
as
some
available
also
not
nice-looking,
commands
the
called
are
and
for
Thus,
file
a
work
some
by
is
design
The
provided a
project
to
processor.
directory
Error
this
EASIE.
and
will
written
of
or
home
command the
displayed
user.
in
this
a
file
window. When name
as
default file
Template directory, is
directory
starts
argument.
define
WorkSpace
changed
an
user
file
include
line
the
name the
basic
(.TPL),
called basic
entered
if
for after
operating and
Procedure base
may
the
system
there
executed
The
(.PROC),
I0
the
EASIE
and
They
are
purpose,
corresponding
system.
The
file contents The
a
this
directory,
format
environment. by
for
use of
Application
home
For no
will
directories.
(.CFG),
is
enter
contents
environment
default
directory.
a particular being
user
easie.input.
Configuration
and
the
Alternatively,
filenames
(.WS),
EASIE,
(.APPL), program a
blank
name may
following
or be is
an
example
format
of
the
easie.input.
/tmp_mnt/home/tsai_c/project/ws.WS /tmp_mnt/home/tsai_c/project/cfg.CFG /tmp_mnt/home/tsai_c/project/tpl.TPL /tmp_mnt/home/tsai_c/project /tmp_mnt/home/tsai_c/project/program /tmp_mnt/home/tsai_c/project/base Figure
The
2.
state
implemented
Basic
diagrams
for
gives
a
EASIE
system.
Environment
user
the
in
Appendix
improved
manual
for
What
File,
A
EASIE
the
follows
new is
define
the
operation
interface.
CCE
a
easie.input
mode
Appendix
interface
description
of
the
B
of
the
new
CCE
interface. Upon a
initialization,
window
the
with
current
eight
the basic
status
or
These
Update,
Organize,
Execute,
a
to
any
further
choose
organized
first
level
of
in sub-menu
in
are
Print,
of
these
a
a
pull-right
a
up and
working Retrieve,
The
user
can
The
main
menu
pull-down
for
pop bar
the
Open,
selections. is
menu in
List.
which
will
main
Tools,
and
hierarchy and
interface
environment
selections
a
mode
selections
operating
area.
mouse
eight
CCE
further
for levels
use is the of
sub-menu. The includes Application,
working the
file Template,
directories. easie.input,
area
These or
the
will
show
names
of
Procedure, data filename
the
WorkSpace, the
are
read which ii
current
home, from the
status
which
Configuration, program, the user
default entered
and
base file,. as
an
argument. not
If
specify
display
The
"OK",
the
the
as
first
file
time
the
updated
system,
be
and
user
or
file
does
system in
the
will working
executing
user
will
If
will
asked
answer
the
be
the
be
the
otherwise,
status
logged
the
during
not.
saved;
the
if the
the
status
will
saved,
or
position
be
the
current
be
name
variables,
will
status
not
such
corresponding
exiting
updated
will
the
the
status
save
status
4.2
on
Before to
no
environment
current
system. whether
is
that
area.
is
updated
kept
as
same
in.
IMPROVEMENTS First,
selecting his/her system user.
we
choice
The
user,
base
for
appropriate
as
the
and
is
provided
to
enter
some
with file
the
on-line
of
a file names.
we
can
factors.
EASIE list
We
12
assist
the
he/she
program
provides
provide a
again,
list
of
offer
the Fifth,
when some
List
limiting we
user.
remove
previous
his/her
for
we
select
utility
also
selecting
for
enhanced
indicates
Finally,
the to
Fourth,
the
to
whenever
status
for
user
help
change
situation,
system
of
provide
system
current
the
help
needs.
a given
The
for
on-line
user
The
windowing
confusion
offer
Third,
confusion
environment
and
he/she
for
a
simpler
the
user.
status.
operating
get
example,
files
memorization
is
we
buttons.
directory
selection
user
memorization
can
for
the it
Second,
user
to
current
and
help
given Thus,
minimized.
the
the
have
choices.
pushes
or
there
all the the
current the
he/she
user needs
unnecessary
and
confusing
mode
(EASIE
R),
Quit
menu
choices,
command
this
T),
of
menu
(EASIE
sequence
(EASIE
command
SAMPLE The
the were
SESSION
mode
recorded
Appendix
number.
highlight mode
reference, previously
in
Screen log
a menu current mouse screen Screen
in
I is
bar
eight
status.
The
device. 2 to 3
shows
the
utility
cancel
a
command
as
a sample
given
in
we
file
this
C
screens
in
n represents put
system
EASIE,
for
Appendix
to
been
EASIE
the of
included
has
the
uses
general
the
together
using
type
to
the
CCE
"easie".
As
"easie.input". file
log-in
log-in
have
For
been
user
can
2 is
the
main
and
resize
the
given
under
the
/tmp
mnt/home/tsai_c/project
shows
the
user
the
the
13
the
the
1 by
using
the
will
use
file,
directory, input
file
includes shown
following
input
users
area
window.
in the
to It
screen
resizing
of
of
presented
a working the
window
contents
contents
screen
characteristics.
selections,
Screen present
command
the
n where
session of
default
with
(EASIE
2.
the
using
Zero:
display
to
References
byScreen
contents
Figure
return
screens
initialize
this
the
is
The
sample
To
Menu
the
MODE
session.
capabilities
above
CCE
session
denoted
environment.
and Q),
THE
the
This
the
described
who
be
Previous
menus
follow.
during
C will
screen
to
to
Toggle
O).
EASIE
user
example,
command
USING
following
CCE
Return
sequence
selection
4.3
for
before
We
examples. easie.input and
it
just
executing
the
program. The
for
the
menu first
levels
of
level
of
Retrieve, the
triangle
The
first
main
menu
after Screen
General
Concept
pop-up
which
the
The
4
shows
can
pop-up
is
a
condition
pushing
the
help
that
there
the
we
select
Note
after
push
Now
and
choice,
the
_pen,
List.
down,
window
is
2ools,
and
the
further
menu
sub-menu.
for
user
a pull-down for
are
sub-menu
pop-up
The
is
main
_rint,
Screen
window.
the
pull-right
the
choice.
help
bar
choice.
shows
in
_xecute,
the
which
a pull-right
level
sub-menus
that 5
and
pull
from
pull-right
above.
the
sub-menu,
selection,
Concept
are
in a hierarchy
Qrganize,
_ools
General there
of
the
L[pdate,
choose
if
organized
sub-menu.
selections
the
is
the
OK
button
in
window
will
be
closed. Screen System up
6
Command
widget,
the
will
be
help
which
widget
widget.
up
Screen
Help
button.
Screen
7,
widget
will
the be
button
and 8
typed
show
is
the If
System closed.
in.
the
the
user
Command The
The
on-line
pop-up
7 is
the
button Help
will
widget
pushes
the
Close
and for
the the
specific
will
the pop
for pushed button
on-line Comment
the The
erase
information help
situation
key.
one
button
pop-
in
Enter
into
A
the
command
on-line
widget
14
system
written
Clear
command.
Screen
strike
and
the
_ystem
up.
the or
generated
user
the
popped
type
Pushing the
choose
be
can Ok
easie.file.
contents
we
will
user
push
command
file,
the
The
and
that
widget
widget.
EASIE
shows
a
that by in help
choice
under
the
_ools
Screen Log
9
shows
choice.
is
the
There
appropriate these
selection
results
are
EASIE
two
10
selection. want
will
represents
be
we
activate
the
pushed
the
the
_ystem
user for
command.
pushes
the
the
clear
by
pushing
generated
an
this
widget,
appeared. widget
are
file
name
he/she
Selection
the
directory.
to,
and
shows help
push
information Screen
clear
Log.
An
each
want
Screen
under to 15
The similar
clear is
the and
the the
presented
Retrieve to
the
Open
buttons
of
shows
Filter
shown
for above.
the
user
the New
file button
the
by
result
the
the
result.
selection
and
selection.
Notice
15
except
for the
will
appear
a
chose
to
change
want
to
change
of
file
Update that
names
Screen the
Help the New
the
in
way
shows
the
be this
name
13
in
of
chose
sub-menu.
the
will
directory.
we
up.
user
list
pushing
filename
popped
bottom
user
Screen
we An
the
The
when
pull-down
WorkSpace
the
is
new
be
above,
how
button.
means
extension
on
Open
directory.
will
described
directory
described
shows
the
the
which
home
.APPL
chosen
Filter
pushing
widget an
The
the
the
with
ii
The
for
14
from
buttons
Screen
Select
widget
sub-choice
the
wants.
modified
the
to
of
column.
then
be
functions
button.
the
will
files
of
sub-choice
dialogue
similar
Filter
_OME
application
all
The
results
the
ACTIVATE-Application-HOME
we
when
sub-choices
command
Next
to
the
to
sub-choices. Screen
In
similar
12
on-line
button. WorkSpace means
current
that
status.
selection the
sub-choice
are
Directory
under
modified
CCE
16
that
shows
under the
the
we
widget.
we
Copy.
be
shown
in
menu
chose
up,
_irectory
want
to
widget
update
A Change-
the
default
Screen
17
are
the
Screen
the
we
and
_pplication
selected, all
the The
this file
is
base
the
similar
names
functions
the
copy-to
file
name.
Bemove,
selection,
selection Next Quit
functions
we
of
Save,
the
Execute are
a
of
pop-
to
choice
Screen
19.
the
20
is
command
and
ReName
sub-choices
how
to to
under
the
functions
exit
the
the
fools
16
a
EASIE
to
the
to
COPYof
functions Orgahize and
mentioned
selection.
file
that
selection,
system.
the
user the
The
19 the
as
the
under
the
pull-
under
similar
choice.
Print
of
same
for
shows
Screen
demonstrate
widget
the
18
selecting
widget
System
selection,
are
are
_opy
extension
widget
COPY-to
this
the
After
Screen
Screen
under
.APPL
this
There
sub-choice
the
similar
consider
EASIE
with
in
widget.
enter
widget
is
of
pop
pop-up
Rename.
_pplication
result
will
The
and
selection.
sub-choice
system
widget.
_rganize
the
the
the
choice. of
that
of
configurations.
this
_ave,
name,
List
improvement
this
widget.
the
_emove,
we
the
of
ACTIVATE-Application-HOME
of the
of
means
popped thls
an
sub-choice
and
of
a look
when
directory.
the
_ASE
programs
will
Copy,
When
presents
to
a look
It
functions
take
result
down
base
be
The
choices:
the
the
is
command's. Now
four
take
selection.
for
will
selection
us
pushed
widget
directory
System
Let
_pdate
Directory
U_pdate
mode.
directory
up
the
the
above. We
select
Screen
2{
shows
the
Screen
choice.
22
whether
is
to
the
the save
means
to
button
means
to
logged
pushes 24
Ok
shows
executing written
into
EASIE
Update,
called
knowing
the
USING
have
selections
the
time
when
be
and
collects
user
Screen during
commands
will
the
the
generated
and
Ok
Cancel
status.
EASIE
user
the
first
result
commands
will
be
to
the
sent
EASIE can
be
For and
the
are
They
the
user
of
these
eight
is
In
of
these
no
longer
commands.
since
performed
by Help
selection.
17
modified
choice As
under
described
is the
Retrieve, follows,
choices.
new
functions
the
it in
what
Some the
EASIE
It
responsible The
information.
commands
Open,
List.
each
as
selections
Tools,
and
the
interface
are
under
this
List
mode
Print,
example,
MODE
CCE There
commands
provides the
the
Execute,
that
CCE
summarizes
window.
structure
interface. selection,
main
noted
automatically
THE
project.
EASIE
the
the
up.
the
Pushing
modified
easie.file,
of
Organize,
be
as
generated
section
this
distribute
should
not
These
SUMMARY
of
EASIE
ask
Pushing
the
the
popped
will
not.
status
saving
be
processor.
in
bar
or
presents
of
information
organized menu
for
file
following
command
we
a
COMMAND The
23
system.
command
4.4
Screen
It
status.
original
example
the
status
modified
the
will
widget.
current
button
an
widget
question
the
keep
in.
the
question
pop-up
save
button
user
A
for
interface
selections
do
of
those
CCE
mode
the above,
!ools some
functions for
example,
Tools S
have
been
added
changing
the
to
the
base
modified or
the
CCE
mode
program
interface,
directory.
Selection
- System command Used to pass a command to Form: S Example: S is
the
operation
system.
C
- Comment Used to place a comment in the command log. This allows notes to be inserted in the log for later reference and clarity. Form: C Example: C enter today's date
CL
- Clear Log Used to remove prior information from a cluttered command log or clear the log completely. Form: CL Example: CL D Allowable object types: D - prior to a given date T - total, a new log started
L
-
Log out Used to give an orderly closeout of the EASIE system, and return the user to the computer's operation system. Before exiting the EASIE, the system will pop up a question widget, and ask the user: "Save Current Status?". If the answer is "OK", the system will save the current status into a file called easie.input; otherwise, it will not save the updated status, and it will keep the original status. After that, the system will close all the windows which the user opened during executing the system. Form: L Example:
Open ACT
L
Selection - Activate Used to
associate
the
indicated
object
with
the
workspace. Form: ACT Example: ACT CFG /tmp_mnt/home/tsai_c/project/cfg. Allowable object types: APPL, CFG, ITPL, OTPL, WS N
- New Used
to
create
a new
object
or 18
get
a fresh
PROC,
object.
user's
CFG TPL,
Form: N Example: Allowable Retrieve TY
-
Type Used
-
types:
to
type TY
the
TY PROC object
indicated
-
-
-
the
terminal.
by
collection
of
variables
IDB,
ODB,
defined
a
data
with database.
any
TPL
Description
RDAPPL object
file description associated procedure, template, or /tmp_mnt/home/tsai_c/project/appl.APPL types: APPL, CFG, ITPL, OTPL, WS
PROC,
TPL,
Selection Edit system editor for certain operations. /tmp_mnt/home/tsai_c/project/proc.PROC types: LOG, PROC, TPL
Change Description Used to change a file description of the indicated object by using the system editor. Form: CD Example: CD TPL /tmp_mnt/home/tsai_c/project/tpl.TPL Allowable object types: APPL, CFG, ITPL, OTPL, PROC, TPL, WS
Orqanize CP
at
as the template.
Used to invoke a Form: ED Example: ED PROC Allowable object CD
file
database. program, "view" of is defined
Example: Allowable
-
PROC
Review
Used to read a workspace, program Form: RD
ED
TPL,
Used to review data from the configuration This command invokes the interactive "REVIEWER" and will display for possible modification a configuration database. A view of a database
Read
Update
CFG,
/tmp_mnt/home/tsai_c/project/proc.PROC types: LOG, PROC, BAT, FILE
Form: RVU Example: RVU IDB Allowable object types: RD
WS,
Selection
Form: Example: Allowable RVU
N WS object
Copy Used Form:
Selection
to
copy one CP
file to
another. 19
a
Example: CP CFG /tmp_mnt/home/tsai c/project/cfg.CFG /tmp mnt/home/tsaic/project/configuration.CFG Allowable object types: APPL, CFG, PROC, TPL, WS, RM
FILE
- Remove Used to remove a file from the user's file directory. Form: RM Example: RM CFG /tmp_mnt/home/tsai_c/project/cfg.CFG Allowable object types: APPL, CFG, PROC, TPL, WS, FILE
SA
- Save Used to save the Form: SA Example: SA PROC Allowable object
CN
work.
- Change Name Used to change the name of a file as indicated. Form: CN Example: CN TPL /tmp_mnt/home/tsai c/project/tpl.TPL /tmpmnt/home/tsai_c/project/template.TPL Allowable object types: APPL, CFG, PROC, TPL, WS,
Execute EX
indicated object for the later /tmp mnt/home/tsaic/project/proc.PROC types: PROC, WS
-
Selection
Execute Used to execute procedure command Form: EX Example: EXAPPL Allowable object
SUB
FILE
an indicated application program file. /tmpmnt/home/tsaic/project/appl.APPL types: APPL, PROC
or
-Submit Used submit a job for batch processing. Form: SUB Example: SUB APPL /tmp mnt/home/tsai_c/project/appl.APPL Allowable object types: APPL
Print PR
Selection
- Print Used to print an indicated file at a local printer. Form: PR Example: PR LOG /tmp_mnt/home/tsai_c/project/log.LOG Allowable object types: LOG, PROC, BAT, FILE
PRVU
- Print Review Used to print a template Form: PRVU Example: PRVU IDB Allowable object types:
or
a view
IDB,
ODB,
2O
of
TPL
the
hard
database.
copy
5.
CONCLUSION
EASIE the
is
needs
alone of
of
consisted
conceptual
engineering
the
EASIE
and
the
well-organized. give
a
considered
in
system,
a
design
is
At concept principles,
the
the
redesign
to
hide
reader mode
to
general and
Although
stand-
selecting
selecting of
menu
users.
menu
menu
this
are
project
This
implemented
the
the
in
not is
to
project the
X
of
the
introduction
current of
and
from minimize concept
some we
paper
EASIE this
By
the
system
is
window
EASIE and
project,
of
menus the
EASIE
this
reorganize
the
and
an
user.
using To
the we
some
a
general
to
the
design
some
flaws.
got are
to
windowing
system
the
Finally, modified
redesign
structures.
reorganize
we
EASIE
is
selecting give
the
system
did.
functionality 21
a
selecting
memorization. about
reader
project
the by
the
comparing
current
improvements enhance
gives
system.
that
selecting
complexity
a
is
objectives
menus
is
the
objectives
EASIE
two
the
structures
the
many
meet
alphanumerical
purpose
by
this
found
selecting
the
the
to
project.
we
Therefore,
and
between
beginning,
about
To
for
two
this
the
EASIE
organized
comparison
of
of main
needs
Since are
the
programs
who
programs.
mode,
principles,
outline
utility
version.
paper
system,
CCE
CCE
of
engineers
structures
to
OSF/Motif This
the
end
set
interface
Thus,
front
a
design
analysis
original
selection,
of
to
the
current
in
EASIE in
system
this
in
project.
format;
does
not
suggest
that
we
may
level widget
be of as
more
mode,
the
the
can
still file
will
minimize
the if
not
menus
to
choice
be of
menu.
22
put
in
the
of
the
buttons
first
level
correct This
Second,
pull-right
choices
bugs
well.
checking.
some
the
be
potential
perform
levels
we
some
must
file-existence
organizing
the
are
input
system
provide
pull-right pushing
there
First,
otherwise,
project
It
CCE
in in of
menus. the the
second pop-up
pull-right
we
REFERENCES
[REF Inc., for 1990
i] X XlI,
...... Toolkit release
[REF 2] Foundation,
, by the Intrinsics 4,
Staff of Reference
Volume
five,
O'Reilly Manual,
O'Reilly
...... , OSF/Motif Style Prentice-Hall, Inc., New
[REF 3] A1 Kelley C, second edition, Inc., California,
and The 1990
[REF 4] Brian W. Proqramminq Lanquaqe, Jersey, 1988
[REF 5] Brian W. Kernighan Environment, Prentice-Hall, [REF 6] Dan Heller, Version, Volume Six, Inc., 1991
& Associates,
Guide, Jersey,
Ira Pohl, A Book Benjamin/Cummings
Kernighan second
Software
On C Proqramminq in Publishing Company,
Pike, The New Jersey,
Proaramminq edition,
[REF 7] Douglas A. Young, The Applications with xt, OSF/MOTIF New Jersey, 1990 [REF 8] James D. Foley, and John F. Hughes, Practice, second edition, U.S.A., 1990
Open 1988
Inc.,
and Dennis M. Ritchie, The C edition, Prentice-Hall Inc., New
and Rob Inc.,
Motif Motif
and Associates, second edition
X
UNIX Proqramminq 1984
Manual O'Reilly
Window edition,
For OSF/MOTIF & Associates,
System Proqramminq Prentice-Hall,
and Inc.,
Andries van Dam, Steven K. Feiner, Computer Graphics: Principles and Addison-Wesley Publishing Company,
[REF 9] James L. Schwing, Lawrence F. Rowell, and Russell E. Criste, The Environment for Application Software Integration and Execution fEASIE) Version 1.0 Volume III Proqram Execution Guide, NASA TM-I00575, National Aeronautics and Space Administration (NASA) Langley Research Center, Hampton, Virginia, April 1988 [REF i0] Software,
Joseph Prentice
S. Dumas, Hall, New
Desiqninq Jersey,
[REF ii] Samul P. Harbison and Guy Manual, 3rd edition, Prentice-Hall, [REF 12] William M. Newman and of Interactive Computer Graphics, Book
Company,
U.S.A.,
1979
23
L.
User
Interfaces
1988 Steele Jr., A Reference Inc., New Jersey, 1991
Robert F. Sproull, second edition,
Principles McGraw-Hill-
for
Master's Project Report
Application
Driven Interface for EASIE
Advisor-
Generation
Dr. James L. Schwing
Apri_2Z, 1992 Department of Computer Science Old Dominion University Norfolk, VA 23529 - 0162
ABSTRACT The Environment interface
for Application
and a set of utility programs
programs
about
execution.
a central
relational
Software
which support database.
One of them is a menu-driven
(ADE),
which
provides
execute
an application
(CCE),
provides
with sufficient program.
an extended
Integration
the rapid integration
EASIE
execution guidance
and Execution,
provides
mode,
called
to review
interface
which
and execution with two
a menu
called Complete
allows
provides
basic
Application-Driven
data, select
The other mode of execution, executive
users
EASIE,
a user
of analysis modes Execution
action-item, Control
in depth
control
techniques
only.
of
and
Execution
of the
design
process. Currently, of this project in a window
the EASIE system to extend system.
in the generation
is based alphanumeric
the flexibility
Secondly,
of an ADE
of the EASIE
a set of utilities application.
interaction system
in the ADE
will be developed
mode
It is the purpose
by implementing
to assist the experienced
engineer
it
Table
of Contents
1. Introduction 2. EASIE:
ADE-modc
2.1 Concepts 2.2 Sample
Considerations
of EASIE system Session
for ADE mode
2.3 Menu Manipulation 2.4 The Drawbacks 3. Principles
in ADE mode
of EASIE in ADE mode
of Interface
4. Modification
Design
of EASIE in ADE mode
4.1 W'mdow System: 4.2 Design
and Construction
OSF's MOTIF
Considerations
4.3 Demonstration
for ADE Facilitator
of the ADE Facilitator
5. The General Stmcmm
of Solution
5.IData Structure 5.2 Mechanisms 5.3 Capabilities
and Limitations
6. Conclusions 7. References Appendix:
program
Listing
of ADE Facilitator
I. Introduction The Environment for NASA
for Application
by Old Dominion
Branch of NASA
Langley,
the task of coordinating EASIE provides and execution with two
engineering
called Complete
Control
in depth control
of the design
directly typed.
known
In general,
process.
system.
the EASIE
study through
system addresses
represents
the execution
to this evaluate
the design
"EASIE
users"
system
programs
against
a final solution
easily
programs
its objectives.
are responsible
used in the engineering engineers".
design
a basic
viewing,
manage
[1].
EASIE
sufficient
program.
provides mode,
guidance
The other mode
executive
interface
can be issued
access
and analysis
system
users called
to review
of execution, which allows
via menu
system,
the EASIE
programs
EASIE
will be referred
its input
selection
or
it also is complicated via the menw-driven
the design
They
of users who be involved
design
to this group as
these users are only interested
system
in
[1]. programers"
and improvement
EASIE
experts
the design
of data required
will refer
to as "application
process.
are the
and the generation
documentation
for the development design
Tiffs group conducts
In general,
and output variables
method
used by engineers applications
user tools
and editing
classes
of modeling
documentation
with respect
or "experts". and
will refer to this
to particular
application
[1].
Considerations
through successive
provides
programs,
with
the engineer/designer/analyst.
aided by EASIE
2. EASIE : ADE-mode
EASIE
to ease
system.
into an EASIE
and can defines
The predominant
design
installed
as "experienced
programs
utility program
execution
of an operating
or, more often, as "designers".
already
group
programs
group
users
the needs of two different
of modeling
These programers/engineers analysis
database
commands
the flexibRity
Analysis
which support the rapid integration
an extended
Most users currently
and Vehicle
is a menu-driven
an application
In CCE,
developed
as ADE.
The first classification
A second
Corporation
which
codes.
provides
(CCE), provides
in the buildup and use of an engineering
executing
of them
which
CCE provides
to use like an operating mode
One
EASIE,
and a set of software
and analysis
and execute
Execution
Although
Sciences
about a central relational
(ADE),
a menu action-item,
and Execution,
and a set of utility programs
of execution.
Execution
Computer
design
programs
modes
Integration
with a methodology
a user interface
Application-Driven dam, select
University,
provides
of analysis
basic
Software
which
of program
environment
and data with the existing
is the iterative
of analysis support
data.
by providing environment.
techniques
the selection
EASIE
technique.
to increasingly and
also provides
the ability
One processes
execution tools
to quickly
ref'med data. of application
for a design
integrate
to
new
team t_ analysis
2.1 Conceptsof EASIE system Conflmn'atlon l)nts: Configur_ion in_facc
data is stored in a systc_
dmbase.
is that data held in the database are anatomically
appUcadon program in an appropria_ made, a copy database
of this "master"
is provided
for review, database
formal
database
on a "read
communicated
is placed
only" basis.
m either a user or an
in a controlled
project
directory.
That is, the users may display
only by the design
user
Once the basic dam definitions and values have been
or they may make copy of the database
can be entered
An advantage of the F._Sm
for their personal
manager
Access
to this
the configuration
files.
Updates
dam
to the master
[1].
Reviewer: The EASIE software
interface
data. Based upon an indicated REVIEWER, to retrieve
provide analysis
using information the necessary
a program program
contained
called the "REVIEWER"
or other dataset in the database
in the database,
input and present
which can access
can then make
any
for a designer,
the appropriate
the
selection
that data at the terminal
Rm.._.ii_tteg The software data templates.
screen forms used to control A data template
by a given Frogram EASIE
process
a list of all data required for input (or supplied
as output)
modify
access
data formats.
to these
the variables
Since
data templates
in the database
data templates
arc generated
is used in conjunction
when
presented
by
with the
during the Review
[1].
FORTRAN
the Formatter
subroutine allowing
2.2 Sample Menu
Session
displayed
interaction
for ADE during
code, called Forma_r data or store
Derived
It consists among
an ADE session
code,
the automatic
generation
of
which can be placed in the application
data into the database
during program
Executive
are typically
of steps to conduct
(ADE)
mode.
for a given application.
these programs
created by experienced some particular
user can easily learn to manipulate
of four short programs
Within the concepts
to enable
execution.
mode
an introductory
with EASIE
relationship
uses the data templates
the proper sequence
such an interface, the AppLication
source
it to retrieve
new users through
system
Finally,
to directly
A final utility called
program
are ca/led
along with their required
utility program.
REVIEWER
is basically
the flow of data to and from the database
Now
we look
This example
that define
and draw
design
activity.
data and execute at an example
illustrates a box.
engineers
capabilities Figure
to guide Given
programs
to describe
in an
of the EASIE
1 represents
the basic
and their data.
of the EASIE system,
we can realize this figure
in a straight forward manner.
Default (pmtecled)
Drawlt ........i:_/iiiilj
Dmwin
tal_s x,y.z
.. .-.
Drsw
!
Boz Progrsm
Boxout t
Figure
.z
vo_umo
I.
Flow
Diagram
For
Sample
Z
Session
Using
EASIE
:'