PrathamIITB Student Satellite Project

Saptarshi BandyopadhyayProject Manager and System Engineer

Pratham, IIT Bombay15th 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 – SPUTNIK2. ASUSAT3. NCUBE4. SSETI5. AAU Cubesat6. SNOE7. ICARUS8. CATSAT9. DTUSAT10. MEROPE11. COMPASS12. 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.

DescriptionMission

Success

Flight Model ready 85%

Beacon Signal received 90%

TEC measurements at

IITB95%

Satellite functional for 4

months100%

Create a learning experience of working on a real life multi-disciplinary complex system.  Learning enhancement throughCDIO (Conceive, Design, Integrate and Operate). http://www.cdio.org/

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:AerospaceChemicalCivilComputer ScienceElectricalPhysicsMechanical

Social Goal

Structure

Quality Team

Integration Team

Comm.

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 weekReviewed by the Team

Once every monthReviewed by the IITB Faculty

Once every 2-3 monthsReviewed by the ISAC Engineers

End of Design PhaseOnce every 6-10 monthsRigorous reviews by the IITB Faculty Mentors & ISAC Engineers

IITB Faculty Mentors: 30 Departments:AerospaceComputer ScienceElectricalMechanicalSystems and Controls

Major emphasis on documentation since “We want to preserve our

knowledge”

All our documents are available on our website www.aero.iitb.ac.in/pratham/

Timeline

Concept feasibility proved to IITBAug 2007

Requirements Capture Phase finished Apr 2008

Conceptual Design Phase finishedAug 2008

Preliminary Design Phase finishedDec 2009

Signed MoU with ISROSept 2009

Detailed Design PhaseAug 2010

LaunchEnd of 2011

Oct

07

Sep

t 0

8

Sep

t 0

9

Mar

10

20Team Size = 30

2520

Two stage selection processQuiz & Presentation

Continuity PlanDocumentation

Ap

r 1

1

D RegionE Region

F1 RegionF2 Region

ION

OSP

HER

E

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 (145.980 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 (437.455 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)

ACTUATORMagnetorquer

ATTITUDE CONTROL

Solar PanelsOn 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

Thank You