Saptarshi Bandyopadhyay Project Manager and System Engineer Pratham, IIT Bombay 15 th May, 2011

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  Satellites are test-beds for new technology that need space qualification 1.MINI – SPUTNIK 2.ASUSAT 3.NCUBE 4.SSETI 5.AAU Cubesat 6.SNOE 7.ICARUS 8.CATSAT 9.DTUSAT 10.MEROPE 11.COMPASS 12.SEEDS

Mission Statement for Pratham Acquiring knowledge in Satellite and Space Technology. Have the Satellite entirely designed by the student body of IIT Bombay. Have the Satellite launched; measure TEC of the Ionosphere above IITB. Involve students from other universities in our Satellite project.  Create a learning experience of working on a real life multi-disciplinary complex system. Learning enhancement through CDIO (Conceive, Design, Integrate and Operate).

Information about Pratham  Weight: ~10 kgs  Size: 260mm X 260mm X 260mm  Payload: Measuring TEC  Orbit: 10:30 polar sun-synchronous, 817km altitude  Downlink at 2 frequencies  Uplink used as kill switch  4 months mission life

Payload Control PRATHAM Power OBC Thermal Student Team Size: 7 (usually 25) Departments: Aerospace Chemical Civil Computer Science Electrical Physics Mechanical Social Goal Structure Quality Team Integration Team Comm. Core Group (10 members) Core Group (10 members)

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 Krithi Ramamritham (CS)  Prof R. K. Pant (Aero)  Prof K. K. Isaac (IIST)  Prof U. N. Gaitonde (Mech)  Prof R. K. Shevgaonkar (PU)  Prof R. N. Banavar (Syscon)  Prof D. K. Sharma (Elec)  Prof R. P. Shimpi (Aero)  Prof Girish Kumar (Elec)  Prof Kavi Arya (CS)  Prof B Bandyopadhyay (Syscon)  Prof C. Amarnath (Mech)

Documentation and Reviews Work done by Pratham Team Once every week Reviewed by the Team Once every month Reviewed by the IITB Faculty Once every 2-3 months Reviewed by the ISAC Engineers End of Design Phase Once every 6-10 months Rigorous reviews by the IITB Faculty Mentors & ISAC Engineers IITB Faculty Mentors: 30 Departments: Aerospace Computer Science Electrical Mechanical Systems and Controls  Major emphasis on documentation since “We want to preserve our knowledge”  All our documents are available on our website

Timeline Concept feasibility proved to IITB Aug 2007 Requirements Capture Phase finished Apr 2008 Conceptual Design Phase finished Aug 2008 Preliminary Design Phase finished Dec 2009 Signed MoU with ISRO Sept 2009 Detailed Design Phase Aug 2010 Launch End of 2011 Oct 07 Sept 08Sept 09 Mar Team Size = Two stage selection process Quiz & Presentation Continuity Plan Documentation Apr 11

D Region E Region F1 Region F2 Region IONOSPHERE Payload Sub-System  Measure Total Electron Count of the Ionosphere over India and France  Expected TEC value is 25±5 TECU (resolution of 0.1 TECU, SNR of 500)  2 polarized radio signals are transmitted parallely  Faraday rotation changes their angle of polarization  The difference in their polarization angles is measured at the ground station

Communication Sub-System  Low bit rate Beacon ( MHz)  CW transmitter, 0.6 Watt power  Resonant Helical/Non-resonant Monopole of 18 cm  High bit rate (1.2kbps) Monopole for downlink of data ( MHz)  FSK transmitter, 0.6 Watt power  Resonant Monopole of 17 cm  NO telecommand  Kill Switch (Uplink) added to satisfy IARU’s constraint for getting license  Resonant Monopole of 17 cm Beacon Crossed Yagi Rotor Base Station

OBC, ADCS and Power OBC Circuit SENSORS SunSensor (LEOS) GPS (ACCORD) Magnetometer (Honeywell) ACTUATOR Magnetorquer ATTITUDE CONTROL Solar Panels On 4 sides (ISAC) Battery (ISAC) Power Circuit

Systems Engineering  System and Sub-System Requirements  Mission Design  Weight Budget  Configuration Layout  Connectivity Diagram  Integration Sequence Mechanical Subsystems  Structural simulation of the satellite under launch loads  Thermal design of the satellite  Integration with IBL230V2 LVI

Testing and Quality Assurance  Electrical Quality ~0.98  From quality calculations, at the end of mission life  Mechanical QA ~1  Validated by testing  Level 1 testing done by individual Subsystems  On Board Computer In Loop Simulations (OILS)  Level 2 testing of Power, OBC, Controls, and Communication  Clean Room built (100,000 class)

Interaction with students from other universities  National Ground station workshops  11 participating universities building Ground Station for Pratham  MHRD Virtual Experiments  2 papers published at the International Astronautical Congress 2010 in Prague  Collaboration with IPGP and Paris Diderot

Organizations Supporting Pratham  ISRO  ISAC  VSSC  IIT Bombay  IRCC  CDEEP  AEA  SAMEER  TIFR  Boeing