Design Procedures
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]
CRITICAL DESIGN REVIEW (CDR)
Design Objectives
Design Objectives
Design Objectives
Primary objective…… States the mission of
your design
The secondary Objective ….. Other
capabilities of your design
CRITICAL DESIGN REVIEW (CDR)
Design Requirements
Requirement Overview
• All components of your design
• Specifications
• Requirements
• Other related matters or the main components of your
requirements
Design Requirements
Design Flow Diagram
Design Requirements
Design Flow Diagram
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.
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
Design Requirements
CONOPs – Concepts Of Operations
Design Requirements
Simulation Block Diagram
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
I2C
Serial
bus
8 analog
line
IMU
Gyro
MAG
Attitude
Ephemerid
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
CRITICAL DESIGN REVIEW (CDR)
Mechanical/Structural Overview
Requirement
• Requirements to be fulfilled:
• Any mathematical analysis.
• Test or repeated test
Structure / Physical Design
• The structure & dimensions:
– Diameter : 6.6 cm
– Height : 11.5 cm
• Any constrain etc
• Special need or design
• Structural materials
• Toughness etc
Body and Structure
Structure / Physical Design
Overall Structure
Structure / Physical Design
CRITICAL DESIGN REVIEW (CDR)
Electrical Power System
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
• Power source
• Battery
• mAH or AH
• Weight/mass/size ?
• Portability?
• Power budget
• Requirement per hour of use
• Connectivity
• Constraint??
Electrical Power Requirements
CRITICAL DESIGN REVIEW (CDR)
Design Requirements
Design Requirements
MMUSat : Weather Monitoring System
• Light Intensity
• Temperature
• Humidity
• Accelerometer (Provided)
Sensors
• Temperature
• Humidity
Reason:
• Small
• Light
• High Accuracy
• Inexpensive
Sensors analyis:
e.g. Sensirion SHT71
Design Requirements
• Infrared Light to Voltage Optical Sensor
• Output voltage is directly proportional to
light irradiance on the photodiode
• Cheap
• Small
• Operation: Automatically light up LED
Sensors:
Sensirion SHT71
Sensors Design Requirements
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
Sensors: Preliminary Result
• Sensor performance
• Suitability
• Sensor test procedures
Sensors Design Requirements
Sensors
Light intensity
Accelerometer
Temperature
Humidity
Microprocessor
Ground Base Station
Concept of Operation
Sensors Design Requirements
Each Sensor concept of operation
Concept of operation
Sensors Design Requirements
CRITICAL DESIGN REVIEW (CDR)
MMUSat : Weather Monitoring System
Data Handling Overview
Data Handling: uProc/uController
MMUSat : Weather Monitoring System
Microprocessor
• The microprocessor and specs
• Why it was chosen
• Other options???
Data Handling: Memory Budget
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
Design Procedures
Integration and Test Overview
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
• Precaution and option if your original design fail
• Preparation of another methods etc
• Preparation of another battery if the original one fails.
Contingency Operations

satellite system design in critical design review phase