Developing an ADCS Prototype for NTNU Test Satellite

91 Pages·2014·43.72 MB·English

by  Øyvind Rein

Developing an ADCS Prototype for NTNU
Test Satellite
Øyvind Rein
Master of Science in Cybernetics
Submission date: June 2014
Supervisor: Jan Tommy Gravdahl, ITK
Norwegian University of Science and Technology
Department of Engineering Cybernetics

Assignment text
The assignment will be about further development of an Attitude Determination and Control System.
It will be a continuation of the specialization project that was written during the fall of 2013. The
long-term goal is to make a functioning ADCS that can be integrated with NUTS (Norwegian
University Test Satellite). Previous master students have done a lot of theoretical work with both
control and estimation algorithms, which provides a foundation for building a prototype of the ADCS.
That way, the theory can be tested in real life. The main topic of this assignment is to build and test
an ADCS prototype. Specific tasks:
 Complete and manufacture the ADCS Module, implement drivers and test hardware
 Assemble an ADCS Prototype, which includes:
o ADCS Module
o Magnetorquers (Coils)
o A structure for mounting
o Placement of photodiodes
o Battery driven power source
o Wireless communication
 Create a Test Platform that can be used to test different control and estimation algorithms.
 Use the Test Platform to test the B-dot detumbling algorithm.

Start date: 07.01.2014
Due date: 01.07.2014

Abstract
NUTS is a student satellite program at NTNU with a goal of launching a cube satellite
intospace. Studentscontributethroughprojects, masterthesesorvoluntarywork. The
satellite will shoot pictures of earth with a camera that will be fixed to the satellite’s
body.In order to accurately point the camera towards the desired target an Attitude
Determination and Control System is required. In this thesis, a prototype of the ADCS
has been developed along with a platform for testing software and control algorithms.
Further, the b-dot algorithm has successfully been tested using the testbed developed.
B-dot is a detumbling algorithm that will be used to stop the satellite’s initial spin
after it is ejected from its pod.

Sammendrag
NUTS er et studentsatellite prosjekt p˚a NTNU med m˚al om ˚a skyte en kubesatelitt
oppiverdensrommet. Studenterharbidratgjennomprosjektoppgaver,masteroppgaver
eller frivillig arbeid. Satellitten vil bruke et fastmontert kamera til˚a ta bilde av jorda.
Av den grunn er det nødvendig med et system som kan endre retningen til satelliten
slik at kamera kan ta blide av et ønsket m˚al. Et slikt system kalles p˚a fagspr˚aket
for Attitude Determination and Control System, eller ADCS. I denne oppgaven er det
utviklet en prototype av ADCS systemet i lag med en platform for˚a teste maskinvare,
programvare og kontrollalgotitmer. Til slutt ble en nedspinnings algoritme, B-dot,
testet i dette oppsettet med suksess. Algoritmens funksjon er˚a stoppe uønsket spinn
som kan oppst˚a etter utløsning fra bæreraketten.
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Preface
This Master Thesis was written during the spring of 2014 at the Norwegian University
of Technology and Science, Department of Engineering Cybernetics. It has been a part
of the student satellite program NUTS (Norwegian University Test Satellite). This
thesis concludes my Master’s degree in Engineering Cybernetics, Robot Control.
I would like to thank my supervisor Jan Tommy Gravdahl for all the guidance and
follow-up throughout the semester. I would also like to thank the whole NUTS team
for all the help and support I have gotten, and I hope my contribution makes up for it.
I wish everyone who have been, or will be, involved with the project good luck. I am
certain all the hard work will be awarded with a successful launch. Finally, I would
like to thank my parents for the all the support, and for always keeping their doors
open, giving me place where I could escape the studies and recharge my batteries.
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