YamSat Introduction YamSat Team Albert Lin (NSPO) Yamsat website - - PowerPoint PPT Presentation

YamSat Introduction

YamSat Team Albert Lin (NSPO)

YamSat

Yamsat website http://www.nspo.gov.tw

YamSat

YamSat Major Characteristics

• Mission:

– Y: ‘Young’, developed by young people. – A: Amateur Radio Communication – M: Micro-spectrometer payload with Micro Electro Mechanical Systems (MEMS) technology

• Orbit: (TBD)
• Launch Vehicle: the Dnepr from the Russian launch site at Baikonour.
• Target Launch Time: Fall 2004 (TBD)
• Mass: within 1kg, Volume: 10cm*10cm*10cm
• Mission Life: 1 month ; Design Life: 2 months
• Power: multi-junction GaAs solar cells, and Si solar cells, surface mounted; rechargeable

battery; secondary voltage 5V

• Amateur Radio Communication: Uplink/Downlink-145.85MHz , Data Rate: 1200bps, half

duplex, FSK; CW downlink frequency 29.355MHz, Morse code, 70 characters/min.

• On-Board Computer: 80C52 micro-controller, 32K bytes external RAM
• Attitude Determination & Control: B-dot control with a magnetometer and magnetic coils
• Passive thermal control
• Structure: Aluminum

YamSat

YamSat Development Schedule

Main Activities Main Activities Start ~ End Start ~ End Period Period

• 1. Working Start Date (WSD)
• 1. Working Start Date (WSD)

2001/03/29 2001/03/29

• 2. Mission Analysis and System Design
• 2. Mission Analysis and System Design

2001/04~05 2001/04~05 2 months 2 months

• 3. System Design Review (SDR)
• 3. System Design Review (SDR)

2001/05/28 2001/05/28

• 4. Preliminary Design
• 4. Preliminary Design

2001/06~07 2001/06~07 2 months 2 months

• 5. Preliminary Design Review (PDR)
• 5. Preliminary Design Review (PDR)

2001/07/24 2001/07/24

• 6. Critical Design
• 6. Critical Design

2001/08~09 2001/08~09 2 months 2 months

• 7. Critical Design Review (CDR)
• 7. Critical Design Review (CDR)

2001/09/27 2001/09/27

• 8. Flight HW Manufacture and Assembly
• 8. Flight HW Manufacture and Assembly

2001/10~12 2001/10~12 3 months 3 months

• 9. Test Readiness Review (TRR)
• 9. Test Readiness Review (TRR)

2002/01/15 2002/01/15

• 10. Satellite Environmental Testing
• 10. Satellite Environmental Testing

2002/01~03 2002/01~03 3 months 3 months Total Period Total Period 1 year 1 year

YamSat

+Y Panel

• Battery
• Magnetic Coil
• X Panel
• Magnetometer
• Magnetic Coil
• CW Antenna x 1
• Z Panel
• TT&C
• Antenna x 1

+X Panel

• Payload_Micro-Spectrometer
• CW Antenna x 1
• Y Panel
• OBMU

+Z Panel

• DRU
• Antenna x 1

X Y Z

Satellite Structure Configuration Satellite Structure Configuration

YamSat

Electrical Block Diagram

Micro- Controller 80C52 D/A Converter OP Amp. Magnetic Coil #1, #2 A/D Converter OP Amp. 3-axis Magneto- meter CW Generator FSK Modulator FSK Demodulator Receiver Transmitter Diplexer Coupler

Battery Battery

Micro- Spectrometer RAM 32KBytes

Solar Array

. . .

x 6

Solar Array

. . .

x 6

DC/DC Converter Power Distribution Power Monitor & WDT Temperature Sensor Current Telemetry Voltage Telemetry Bilevel Output Bilevel Input

Fiber Coupler 3.75V +5V, -5V To Units Rx Rx Bi 145.85MHz 145.85MHz 29.355MHz Bi Coupler

YamSat

t   

FOV

t   

Payload: Micro-Spectrometer

By PIDC

• Study the atmosphere elements by measuring the sunlight scattering

spectrum from the atmosphere. The measurement characteristics of the micro-spectrometer payload are: detection spectrum range 380nm ~ 780 nm, 256 bands, 12 nm resolution per band.

• Study the atmosphere condition from the unusual albedo value, e.g.

volcanic aerosol using micro-spectrometer by measuring the solar energy reflected from the Earth (Albedo).

• In addition, user can also study the Ionosphere’s effect on RF wave

propagation, specially for 29MHz.

YamSat

Micro-Spectrometer Block Diagram

By PIDC 102/122 Quartz-Quartz Fiber CMOS Detector 256 Pixels MEMS Diffraction Device LED Pre-Amplifier A/D Single Chip Micro-Controller

BUS/Payload Interface

Power Line/ 5V F#2 Quartz Lens Clock/Driving Line 8 Bits Serial Signal

Optical Subsystem

Electronic Circuit

259 Bytes/1.172sec 2400 bps

YamSat

Irradiance Calibration System Diagram

Integration Sphere Monochromator

MEMS Diffraction Device

Standard Detector Lens Fiber MicroSpectrometer RS232 Power Supply

5V/DC

Power Meter

MicroSpectrometer:

LED:

LED Power Meter Spectrometer

Power Supply and Monitoring

………. 380 780

YamSat

Yamsat Stress Distribution

YamSat

ADCS Subsystem Design

• Control System Block Diagram

Environmental Disturbance S/C Dynamics Magnetic Coil H/W Model B-dot Control Law 2nd Order Low-pass Filter Earth’s Magnetic Field

B : Magnetic Flux Density B (Filtered) Implemented by Flight Software ADCS Hardware (Magnetic Coils) ADCS Hardware (Magnetometer)

• 1. Q : Attitude
• 2. 

: Angular Rate M : Magnetic Moment Td : Disturbance Torque P : S/C position

Eclipse limit sunlight

Z X Z X Z

• Y

X Z X Z X Z X Z X Z X Z X Z

• Y

X Z X

YamSat

FSW Executive Loop – Flow Diagrams

Reset Initialization Command ISR Payload Data ISR Executive Loop

Executive Loop Initialization

Timer ISR CMD Reception Task CMD Processing Task P/L Data Reception Task P/L Data Storage Task Actuator Output Task Telemetry Packet Task ADCS Task EPS Task Telemetry Transmit Task Sensor Input Task Background Built-in Task CRC Checking Task CMD execution Task

YamSat

YamSat 1A & 1B

Items YamSat-1A YamSat-1B Purpose Final Flight Backup; Demonstration; Fit Check Solar Panel with Cells 1 Si +5 GaAs 6 Si Battery E-ONE ICR 18500A Panasonic P-150S Low Battery Voltage Cutoff Circuit For ICR 18500A For P-150S CW Antenna Wires with Teflon coating, and metal

• supporters. (better

protection) Wires with enamel coating Mass 867g 843g Others Same Same

YamSat

Thermal Cycling Test

By NSPO

YamSat

Thermal Vacuum Test



Test Condition: YamSat-1A is under 5x10-7mbar vacuum condition.

By PIDC

YamSat

YamSat 1-A/B Vibration Test



Test Condition: YamSat is installed in Test P-POD



Sine Sweep Test: freq range: 1600 Hz,Sweep rate: 2

• ct/min, Test level: 0.2g

– Sine Burst: Test freq : 20 Hz Test cycle: 40

cycles, Test level: 10.25g

– Random Vibration

By NSPO

YamSat Ground Systems to YamSat End-to-End Test



One amateur ground station uses two YAGI antennas for VHF communication with 12dBi-antenna gain and 100W-transmitter power to receive both YamSat telemetry and Morse code signal sent from the amateur communication payload.



Continuous wave (CW) circuit generates tracking beacon and SOH data under the control of the on-board controller.



The Call sign of the ground station is “BN0SPO” and the call sign of the YamSat is “BN01A”.

By NSPO

YamSat

Frequency Coordination

 YamSat Call Sign: BN01A

YamSat

Batteries Capacity Test  The YamSat-1A Flight Battery capacity was retested on 2004/3/4.

– Charge Condition: maximum charge current is 1 Amp., maximum charge voltage is 4.2V – Discharge Condition: fixed discharge current 0.28 Amp., end of discharge voltage is 2.5V – YamSat-1A Flight Battery capacity is 3.6 Amp-Hour.

YamSat Battery Discharge Curve

1 2 3 4 1 3601 7201 10801 14401 18001 21601

Discharge Time (Sec)

Ba tte ry Volta ge Discha rge Curre nt (A) Discha rge Ca pa city (AH)

YamSat Battery Charge Curve

1 2 3 4 5 1 3601 7201 10801 14401 18001

Time (S ec)

Ba tte ry Volta ge (V) Cha rge Curre nt (A) Ba tte ry Cha rge Ca pa city (AH)

YamSat

YamSat-1A RF Pattern - VHF

 Retest YamSat-1A RF patterns in NSPO Anechoic

Chamber on 2004/03/24. The test distance is 9.28m.

YamSa-1A with flight battery, 0 deg orientation, VHF pattern YamSa-1A with flight battery, rotation, VHF pattern

YamSat

YamSat-1A RF Pattern - HF

YamSa-1A with flight battery, 0 deg orientation, HF pattern YamSa-1A with flight battery, rotation, HF pattern with Morse codes

YamSat

Involved Domestic Organizations

Rechargeable Battery

台翔航太工業股份有限公司 : Structure Manufacture

: Attitude Analysis : Space Science Research Electrical Board Soldering : Micro-controller & RAM : Solar Array Assembly : Amateur Radio League Antenna Deployment, Ground Station System Integration, Subsystem Design, I&T, Flight Operation PIDC: Micro-Spectrometer