Cubesats

1. Cubesats STUDENTS’ SATELLITES IN SPACE

2. AMSATS : • AMSAT is a short notation for an amateur satellite. • AMSATS have been first in a number of satellite technologies including store and forward messaging. • For decades ,the amateur radio community has been building and flying their series of amateur satellites . • Amsats have also become the models for the small sat revolution. • Thekey to the success of amsats and student satellites is obtaining a cheap ride to orbit.

3. ORIGIN OF CUBESAT DESIGN: • The CubeSat Project is a international collaboration of over 40 universities, high schools, and private firms developing picosatellites containing scientific, private, and government payloads. • Low Earth Orbit space missions • Cost to complete a CubeSat mission ranges from $65,000 to $ 80,000 • Life span of about 9 months on an average • AMSATS are already a hot topic in aerospace. • Worldwide interest is focused on Cubesats in particular, • partly because they are becoming a de facto standard.

4. USE OF CUBESATS: • The CubeSat initiative is a global congregation of universities and private firms striving to advance small satellite technology. • Opportunity for students to apply their classroom instruction in a real-world project • Learning while building • Enhancement of student engineering skills (by carrying out science data gathering or supporting a commercial space agenda.) • Shift of focus towards higher end applications • In addition to receiving real-world experience, students also make contacts with potential employers.

5. A CUBESAT KIT EXTERNAL STRUCTURE

6. LAUNCHING FACILITY: • Cubesats are often launched in groups from dedicated • launchers as secondary payloads on a rocket. • The CubeSat design specification is proposed by Stanford and Cal Poly San Luis Obispo universities. • The primary responsibility of Cal Poly is to act as a launch coordinator and to ensure the safety of the Cubesats and protect the launch vehicle (LV), primary payload, and other • Cubesats. • Cubesats are usually ejected from a P-POD launcher.

7. THE P-POD LAUNCHER: • The Poly Picosatellite Orbital Deployer(P-POD) is Cal Poly’s • standardized CubeSat deployment system. • Capable of carrying three standard Cubesats and serves as the interface between the Cubesats and LV. • Aluminum, rectangular box with a door and a • spring mechanism.

8. CONSTRAINTS IN CONSTRUCTION: NON-TESTING REQUIREMENTS: • Each single CubeSat may not exceed 1 kg mass. • Center of mass must be within 2 cm of its geometric center. • Double and triple configurations are possible. • Compatibility with p-pod. • The use of Aluminum 7075 or 6061-T6 is suggested for the main structure. • Deactivation of all electronics during launch to prevent any electrical or RF interference with the launch vehicle and primary payloads.

9. • Deployment of antennas 15 minutes after ejection from the P-POD (as detected by CubeSat deployment switches). • Providing documentation of proper licenses for use of frequencies. (this requires proof of frequency coordination by the International Amateur Radio Union (IARU).)

10. TESTING REQUIREMENTS: The following tests are performed before the launch of a CubeSat into space • Component tests • System tests • Vibration tests • Thermal vacuum tests • Electromagnetic interference tests • Integration tests

11. BUDGET ALLOCATION:

12. POWER BUDGET:

13. CUBESAT SUBSYSTEMS: • Power generation and distribution system(PG&D) • Tracking, telemetry and command(TTC) • Mechanical structures and analysis(MSA) • Data and command handling • System integration and testing

14. POWER GENERATION AND DISTRIBUTION SYSTEM: • Provides the power for the CubeSat’s electronic components. • Generated with high-efficiency gallium arsenide solar cells • Storage of power in lithium-ion cells

15. BLOCK DIAGRAM FOR PGD SYSTEM

16. Tracking,telemetry and command Telemetry: A system that reliably and transparently conveys measurement information from a remotely located data generating source to users located in space or on Earth. Tracking: A system that observes and collects data to plot the moving path of an object. Command: a system by which control is established and maintained. • Responsible for all satellite communications, on the satellite and on the ground. • The communications system operates in the UHF range, to take advantage of the worldwide network of amateur radio operators that operate in the same frequency range.

17. BLOCK DIAGRAM OF TTC SYSTEM

18. MECHANICAL STRUCTURES AND ANALYSIS: The team has a twofold task • To determine the temperature gradients throughout the CubeSat • Design and fabrication of all the mechanical support structures needed for the satellite, including vibration and thermal stress simulation and testing. • The thermal subsystem uses control techniques to keep the satellite and its subsystems within the allowable temperature limits. • The subsystem shall be turned off during ground operations, launch, and ascent of the satellite. • Passive mode in orbit, with the active control turned on as needed.

19. BLOCK DIAGRAM OF THERMAL SYSTEM:

20. DATA AND COMMAND HANDLING SYSTEM: • The microprocessors and other digital support circuitry necessary to make the CubeSat operate, as well as all of the software requirements are taken care of • Automated tasks run by a Rabbit Semiconductors microprocessor • Programmable integrated circuits (PIC) chips to aid the Rabbit processors in data routing and handling throughout the satellite • PIC Serves as backup processor in case of failure of main OBC • C rules here. • Onboard memory

22. ATTITUDE DETERMINATION AND STABILIZATION • Used to track Cubesats in space and maintain • updated orbit parameters. Following equipment are used for attitude determination: • Magnetometers and Sun Sensors • Gyroscopes • Linear Accelerometers Following equipment are used for attitude control • Momentum wheels • Magnetorquers • Thrusters

23. VACUUM ARC THRUSTER LOCATIONS OF THRUSTERS A SUN SENSOR

24. PAYLOADS: • First used in beacon mode • Satellite imaging • Measuring changes in atmospheric density • In-orbit tests • To measure the radiation environment on the satellite’s near orbit. • SETI ………AND LOTS MORE!

25. MISSION STATISTICS: • Inherent freedom to fail • 3 out of 6 Cubesats failed to respond in 2003 • A rocket carrying 14 Cubesats exploded few minutes after launch in 2006 • Next mission scheduled on Jan 17 this year

26. A number of CubeSat projects are running in different universities currently. Some of them are: BillikenSat-II by Parks College, Saint Louis University, U.S. Delfi-C3 by Delft University of Technology, The Netherlands : It is a 3-unit CubeSat 10x10x30 centimeters AAUSAT-II by Aalborg University, Denmark AubieSat-1 by Auburn University, U.S. Compass One by Fachhochschule Aachen, Germany TIsat-1 by the University of Applied Sciences of Southern Switzerland (SUPSI), Switzerland 7.DTUsat-2 by Technical University of Denmark, Denmark

27. 8.DTUsat-2 by Technical University of Denmark, Denmark 9.CAPE-1 by University of Louisiana at Lafayette, U.S. 10.CASsat jointly by University of Sydney and University of Technology, Sydney, Australia 11.CAPE-1 by University of Louisiana at Lafayette, U.S. 12.Hermes by University of Colorado at Boulder, U.S. 13.PolySat by California Polytechnic State University, U.S. 14.Swiss Cube by the Swiss Federal Institute of Technology, Switzerland 15.MEROPE by Montana State University, Space Science and Engineering Laboratory

28. A NORWEGIAN CUBESAT A GRID OSCILLATOR ANTENNA A TRIPLE CUBESAT THE FIRST CUBESAT

29. Some Cubesats A thruster integrated on a chip

31. THANK YOU……….