satellite system design in critical design review phase

satellite design

1. Design Procedures

2. Design Defination
System
<< A set of functional elements organized to satisfy
user needs >> (IEEE P1220)
Mission/Objective
<< Specific task, duty or function defined to be
accomplished by a system >> (EN 13701:2001)
Requirement
<< Need or expectation that is stated, generally
implied or obligatory >> [ISO 9000:2000]

3. CRITICAL DESIGN REVIEW (CDR)
Design Objectives

4. Design Objectives
Design Objectives
Primaryobjective……Statesthemissionof
yourdesign
ThesecondaryObjective…..Other
capabilitiesofyourdesign

5. CRITICAL DESIGN REVIEW (CDR)

6. Design Requirements
Requirement Overview
•Allcomponentsofyourdesign
•Specifications
•Requirements
•Otherrelatedmattersorthemaincomponentsofyour
requirements

7. Design Requirements
Design Flow Diagram

8. Design Requirements
Design Flow Diagram

9. Design Requirements
Process Flow Diagram
Initialize
SGP4
IGRF
SUN
Payload On
Measure
MAG
IMU
Compute
EKF1
EKF2
Estimate
Attitude
Ephemerid
Store Data
Attitude
Ephemerid
Software Process Flow.

10. Design Requirements
Process Flow Diagram
Operation Process Flow.
1.0
Launch
2.0
Commissioni
ng
[co-proc. is in
good working
order]
3.0
Normal
Operati
on 3.1
MAG
3.2
MAG
3.3 EKF
on
3.4
ADS /
ODS on
3.5
pass /
store
data
3.6
MAG
off
3.2a
Calibrate
MAG
O
K?
N
Y
4.0
Error
4.1
Error
recover
y
4.2
Termina
tion

11. Design Requirements
CONOPs –Concepts Of Operations

12. Design Requirements
Simulation Block Diagram

13. Design Requirements
Functional Block Diagram
Analog input
RCM 3400
4 to 1
Analo
g
Mux
Digital control line
Ch A
Ch B
Ch C
Ch D
Digital
Prog
line
TI
MPS 430
OBC
Data
bus
I
2
C
Serial
bus
8 analog
line
IMU
Gyro
MAG
Attitude
Ephemerid

14. Design Overview
Design Overview
9V
Power Subsystem
Transceiver
Communications System
Sensor Payload
VREG
ADC
Microprocessor
Data Handling Unit
Humidity
5V & 3.3V Power
GPS
Temperature
Accelerometer
Wireless Camera
Antenna
Patch Antenna
Monopole Antenna
Light Intensity

15. CRITICAL DESIGN REVIEW (CDR)
Mechanical/Structural Overview

16. Requirement
•Requirementstobefulfilled:
•Anymathematicalanalysis.
•Testorrepeatedtest
Structure / Physical Design

17. •Thestructure&dimensions:
–Diameter:6.6cm
–Height:11.5cm
•Anyconstrainetc
•Specialneedordesign
•Structuralmaterials
•Toughnessetc
Body and Structure
Structure / Physical Design

18. Overall Structure
Structure / Physical Design

19. CRITICAL DESIGN REVIEW (CDR)
Electrical Power System

20. Electrical System Block Overview
Serial Terminal
Microprocessor
9V Power Supply Voltage Regulator
5V Power Supply
3.3V Power Supply
GPS
CMOS Camera
Sensor 1
Sensor 2
Sensor 3
Monopole Antenna
Ground Station
MMUSat

21. •Powersource
•Battery
•mAHorAH
•Weight/mass/size?
•Portability?
•Powerbudget
•Requirementperhourofuse
•Connectivity
•Constraint??
Electrical Power Requirements

22. CRITICAL DESIGN REVIEW (CDR)
Design Requirements

23. Design Requirements
MMUSat: Weather Monitoring System
•Light Intensity
•Temperature
•Humidity
•Accelerometer (Provided)
Sensors

24. •Temperature
•Humidity
Reason:
•Small
•Light
•High Accuracy
•Inexpensive
Sensors analyis:
e.g. SensirionSHT71
Design Requirements

25. •InfraredLighttoVoltageOpticalSensor
•Outputvoltageisdirectlyproportionalto
lightirradianceonthephotodiode
•Cheap
•Small
•Operation:AutomaticallylightupLED
Sensors:
Sensirion SHT71
Sensors Design Requirements

26. Sensors Testing: Preliminary Result
•Experiment on sensor for suitability of usage
0
5
10
15
20
25
30
35
06:05pm 06:35pm 07:05pm 07:35pm 08:05pm 08:35pm 09:05pm 09:35pm 10:05pm 10:35pm 11:05pm 11:35pm 12:05am 12:35pm 01:05am 01:35pm 02:05am 02:35pm 03:05am 03:35pm 04:05am 04:35pm 05:05am
Temperature (
o
C)
08082007 -EX1 Temperature Versus Time
Thermometer
Sensor1:
Temperature
Telemetry
Sensor2:
Temperature
Sensors Design Requirements

27. Sensors: Preliminary Result
•Sensor performance
•Suitability
•Sensor test procedures
Sensors Design Requirements

28. Sensors
Light intensity
Accelerometer
Temperature
Humidity
Microprocessor
Ground Base Station
Concept of Operation
Sensors Design Requirements

29. Each Sensor concept of operation
Concept of operation
Sensors Design Requirements

30. CRITICAL DESIGN REVIEW (CDR)
MMUSat: Weather Monitoring System
Data Handling Overview

31. Data Handling: uProc/uController
MMUSat: Weather Monitoring System
Microprocessor
•Themicroprocessorandspecs
•Whyitwaschosen
•Otheroptions???

32. Data Handling: Memory Budget

33. RCM 3400
Master
Bus
controlle
r
Memory
Allocation
(SRAM)
SPI
Serial
Bus
SLAVE
nIMU
&
Sensors
OBC MSP 430
Other
Peripherals,
(Sensors,
Actuator)
MASTER
RS232
Programming
Bus
Modem
I2C
SPI
Data Flow Block Diagram

34. Design Procedures
Integration and Test Overview

35. Integration and Test Overview
RCM 3400
Master
Bus
controlle
r
Memory
Allocation
(SRAM)
SPI
Serial
Bus
SLAVE
nIMU
&
Sensors
OBC MSP 430
Other
Peripherals,
(Sensors,
Actuator)
MASTER
RS232
Programming
Bus
Modem
I2C
SPI

36. • Precautionandoptionifyouroriginaldesignfail
• Preparationofanothermethodsetc
• Preparationofanotherbatteryiftheoriginalonefails.
Contingency Operations