Design and Performance of the BOPPS UVVis Fine Pointing System

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fine pointing system (FPS), designed for science pointing on the ... telescope, three axis control system, and two instruments. The John ... of custom software.
Design and Performance of the BOPPS UVVis Fine Pointing System Jed Diller Southwest Research Institute 1050 Walnut St. Boulder, CO 80302 303-546-9670 [email protected]

Kevin Dinkel Southwest Research Institute 1050 Walnut St. Boulder, CO 80305 303-546-9670 [email protected]

Abstract-In September, 2013 the BRRISON mission suffered an anomaly resulting in a total loss of science data for the duration of flight.

The Balloon Observation Platform for

Planetary Science (BOPPS) mission is in essence a re-flight of the BRRISON mission. The BOPPS mission was designed to study multiple comets and other planetary bodies as well as demonstrate a fine pointing system. The performance of this fine pointing system (FPS), designed for science pointing on the

Zach Dischner Southwest Research Institute 1050 Walnut St. Boulder, CO 80305 303-546-9670 [email protected]

Eliot Young Southwest Research Institute 1050 Walnut St. Boulder, CO 80302 303-546-9670 [email protected]

the gondola and BIRC infrared instrument. The UVVis instrument, housing a near ultra-violet detector, visible detector, and the fine pointing system, was built by Southwest Research Institute in Boulder, CO. BOPPS launched from Fort Sumner, NM on September 25th, 2014. Figure 1 below outlines the payload in stowed and un­ stowed configurations.

50 milliarscecond level, will be discussed along with the mission as a whole. Due to a telescope focusing issue that manifested in flight during the allocated FPS demonstration window,

thorough

FPS

characterization

could

not

be

performed. However, a calibration dataset demonstrated stable pointing of 33 and 58 milliarcsecond (mas) RMS in instrument Azimuth

and

Elevation

respectively.

This

performance

is

Telescope without baffle extension

considered marginal given the conservative FPS settings it was UWIS optical bench

acquired with.

BIRe optical bench

Table of Contents

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1. INTRODUCTION AND BACKGROUND 2. HARDWARE 3. SOFTWARE 4. TESTING

BIOGRAPHY

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5. FLIGHT RESULTS

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Figure 1: BOPPS Gondola Overview [1]

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A primary challenge while gathering planetary science data is the small, distant, and dull nature of targets. To get high quality images from a balloon in the stratosphere, arcsecond level pointing must be maintained while the gondola is being perturbed by stratospheric winds. These winds act on the balloon, flight train, and gondola, exciting pendulum­ like dynamics. The BOPPS gondola attempts to achieve this arcsecond level pointing using a three part control system highlighted in Figure 2 below.

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REFERENCEs

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6. SUMMARy

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1. INTRODUCTION AND BACKGROUND

The BOPPS (Balloon Observation Platfonn for Planetary Science) mission was conceived with the science goals of collecting infrared, ultra-violet, and visible images of the comets Siding Spring, PanSTARRS, and Jacques, as well as other planetary targets like Ceres and Uranus. BOPPS is a re-flight of the 2013 flight of the BRRlSON (Balloon Rapid Response for ISON), which suffered an in-flight anomaly and was unable to collect any science data. The performance characterization of a fine pointing system was a primary project goal and is the focus of this paper. The BOPPS high altitude balloon gondola is comprised of a 0.8 meter telescope, three axis control system, and two instruments. The John Hopkins Applied Physics Laboratory (APL) built 978-1-4799-5380-6/15/$31.00 ©2015 IEEE

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Figure 3: STO gondola residual motion is frequencies < 5Hz Figure 2: BOPPS gondola and coarse control components in Fort Sumner, NM