Presentation Transcript

1. PrathamIITB Student Satellite SaptarshiBandyopadhyay Project Manager and System Engineer Pratham, IIT Bombay 12th March, 2010
2. Student satellite – The Idea! Aim - To develop a satellite in a time frame of 2-3 years be of low cost low mass (< 10kgs) launch it into orbit COTS instruments to reduce costs Success of mission attached to process of learning, not just final output MINI – SPUTNIK ASUSAT NCUBE SSETI AAU Cubesat SNOE ICARUS CATSAT DTUSAT MEROPE COMPASS SEEDS
3. Grand Plan forIIT Bombay Student Satellite Project Make IIT Bombay a respected center for advancement in Satellite and Space Technology in the world Launch at least 5 satellites within the next few years Satellites as test-beds for new technology that is being developed in the institute and need space qualification
4. Mission Statement for Pratham Acquiring knowledgein Satellite and Space Technology. Have the Satellite entirely designedby the student body of IIT Bombay. Have the Satellite launched; measure TEC of the Ionosphere above IITB. Involve students from other universitiesin our Satellite project.
5. Success Criteria
6. Vital Statistics of Pratham Weight ~ 10 kgs Size 260mm X 260mm X 260mm LVI from VSSC Solar panels on 4 sides Orbit 10:30 polarsun-synchronous, 817km altitude 3 pre-deployed monopoles Downlink at 2 frequencies(145MHz and 437MHz) No tele-command, fully autonomous 4 months mission life
7. Team Size: 38 Departments:AeroChemCivilCSElecEPMech PRATHAM Integration Team Quality Team Core Group (10 members) PR Team Structure OBC Power Comm Thermal Payload Control Mechanism
8. Technical Mentors Prof K. Sudhakar (Aero) Prof P. M. Mujumdar (Aero) Prof H. Arya (Aero) Prof H. B. Hablani (Aero) Prof S. P. Bhat (Aero) Prof K. Chatterjee (Elec) Prof B. G. Fernandes (Elec) Prof K. N. Iyer (Mech) Dr K P Ray (SAMEER) Prof Madhu N. Belur (Elec) Prof KrithiRamamritham (CS) Prof R. K. Pant (Aero) Prof K. K. Isaac (Mech) Prof U. N. Gaitonde (Mech) Prof R. K. Shevgaonkar (Elec) Prof R. N. Banavar (Syscon) Prof D. K. Sharma (Elec) Prof R. P. Shimpi (Aero) Prof Girish Kumar (Elec) Prof KaviArya (CS) Prof B Bandyopadhyay (Syscon)
9. Timeline
10. Payload Total Electron Count - Ionosphere TEC map above Ground Station Ionosphere Tomography Method used - Faraday rotation Social Goal Ground station workshops 11 participating universities MHRD Virtual Experiments Collaboration with IPGP, France
11. TEC Coverage over the World
12. Communication and Ground Station Low bit rate Beacon (145MHz) High bit rate (1.2kbps) Monopole for downlink of data (437MHz) NO telecommand Linearly polarized radio signals 2 crossed yagisat ground stations to receive data and measure their polarization Low cost ground stations for other universities(approx INR 25000/-) Kill Switch (Uplink) added to satisfy IARU’s constraint for getting license
13. Attitude Determination and Control Goal Stabilize the satellite after deployment Maintain 3 axis attitude stabilization of the satellite Sensors GPS (1) Single axis sun sensor (6) Magnetometer (1) Actuators Magnetorquer (3) Control law Linear controller Kalman Filter for sensor fusion Stability Analysis Robustness Analysis Manufacturing accuracies needed Estimator and Controller fully functional Monte Carlo simulations running
14. On Board Computer Subsystem Hardware Two ATMega 128 micro-controllers One Interfaces with Power, Sensors and Actuators (master) Other dedicated to CC1020 (slave) Hardware Busses SPI I2C UART External EEPROM Final Hardware designs ready Software Minimal pre-empting of running task Cyclic Scheduler Software almost ready
15. Power Subsystem Hardware Solar cells Batteries 3.3V regulator 5V regulator Microcontroller Power distribution Battery protection Software ready Major power inputs Direct solar radiation Solar radiation reflected from Earth (albedo) Earth’s thermal radiation Average useful power incident on the faces
16. OILS (HILS) Level 2 testing for Power, OBC, Controls, and Communication Hardware ready Working on Real-time Software
17. Structure Subsystem Static Analysis: Displacement Qualification of the satellite structure as per launch loads Qualification of structure based on thermal loads in orbit Software – ANSYS Analysis of final model has started Modal analysis: 1st mode
18. Thermals Subsystem Maintain suitable temperature for components. Temporal cycle of temperatures experienced in orbit Spatial gradient of temperature at an instant Dissipation of heat from components onboard Active thermal control of critical components Fluent to Nastran to our own C++ codes to ISAC’s Ideas Going to ISAC for final Thermal design
19. Mechanisms Subsystem Deployment of 2 parallel monopoles (ditched!) IBL – 230 V2, Micro Satellite Separation System SNAP Mechanism –Separation from LVI To be given by VSSC
20. System Engineering and Integration Stages and Functions of Satellite; Operational Sequence System and Sub-System Requirements Budget for Weight, Power and Data Interface, Connectors and Wires Routing of Wires Configuration Layout (External / Internal) LVI from ISRO and Access Ports Connectivity Diagram Integration Sequence Level 2 and Level 3 Testing
21. Quality Assurance “ QA refers to planned and systematic production processes that provide confidence in a product's suitability for its intended purpose ” Electrical QA Mechanical QA (~1) Software QA Clean Room being built (100,000 class)
22. Documentation and Reviews Major emphasis on documentation “ We want to preserve our knowledge ” Regular review done by the team and faculty Reports written and circulated within the team Reviews done in ISAC and by other ISRO scientists All our documents are available on our website www.aero.iitb.ac.in/pratham/
23. Organizations Supporting Pratham ISRO ISAC VSSC IIT Bombay IRCC CDEEP AEA SAMEER TIFR Boeing
24. Why we need you! Number of students in the team during summer will drop, due to summer interns. Most of these students have already been with us for over 2.5 years Hence strong technical skills in electrical and mechanical subsytems required. Students will be trained after they join the team. Grading of freshies, sohpies and mtech will be done separately All students need to pass through quiz followed by presentation for entering the team.
25. What you will do? Design should be over by then. But you should have capability to understand design and suggest changes if faults are found. Testing of the Qualification and Flight Model Fabrication of Flight Hardware – ISAC, Bangalore Conformal Coating of circuits ThermovacTest – TIFR, Mumbai Vibration Test – TIFR Hyderabad, ISAC Bangalore Other Tests – SAC Ahmedabad, ISAC Bangalore Integration with LV – VSSC, Trivandrum Launch of the Satellite – SHAR, Shriharikota
26. Quiz (Wed, 24th March, 2010) Electrical Mechanical Need good knowledge of structures, thermals, mechanisms, etc. Read up on integration, wire routing, system engineering, budgeting of weights, etc. Knowledge about mechanical structure of Pratham Sub-Systems: Mechanism, Structures, Thermals, System Engineering, Integration, Need good knowledge of circuit design, electronics and communication fundae, controls, quality etc. Electrical components on Pratham like GPS, Magnetometer, SS, etc. Knowledge about 6 electrical boards onboard Pratham Sub-Systems: Payload, Comm, Controls, OBC, Power, OILS, Quality
27. Thank You