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Temple University Advisors: Dr. John Helferty & Dr. Chang-Hee Won
Charles Wright Jinyan Chen
Billy Cheng Brittany Gray
1
Objectives Design, Build, And Test A
Vibration Suppression System To Counteract Launch Vehicle Vibrations
Measure The Vibration Environment Inside The Terrier-Orion Rocket Will Use Two Identical Vibration
Measurement Systems ○ A Custom Built Passive Damping
System ○ Rigidly Attached System
2
Goals
Dampen The Magnitude Of The Vibrations By A Magnitude Of 5 To 1 Measurements Will Be Compared From
Damped To Undamped System After Flight
3
Benefits
Efficient Vibration Isolation Systems For Small Payloads Increased Operational Performance Of
Onboard Sensing Equipment Better Protection Of The Sensing
Equipment
4
Related Experiments
Paper by D.I. Carantu and C. Shove Titled “Overview of Payload Vibration Isolation Systems” Tested Vibrations On Small Sounding
Rockets They Were Able To Find The Following ○ Most Passive Vibration Systems Do Not
Achieve Greater Than A 5 to 1 Ratio ○ Passive-Active Vibration Systems
Achieved A 10 To 1 Ratio
5
Concept Of Operations
Rocket Launch
G-Switch Activated
RBF Wires Connected
Accelerometers (x,y,z)
Activated
AVR Activated
Flash Memory
Activated
Level Translator Activated
Rocket Splash
Payload Retrieval
System Deactivated
6
Expected Results
Achieve A Passive Damping System With 5 to 1 Damping Ratio Ratio Refers To The Magnitude Of
Vibration Data Logging For Entire Flight Sufficient Power For Entire Flight
7
Functional Requirements Requirement Method Status
The payload must not exceed ~6.5bs (~2.94kg). Design
Two (2) 9-Volt batteries will supply power to each system. Design, Test
The payloads’ center of gravity (CG) shall be within 1 cubic inch of the canister’s centroid.
Design, Test
The allowable static envelope of the payload is cylindrical with a diameter of 9.3” (cm) and a height of 4.7” (cm).
Design
The payload must interface to the ten (10) bulk head screw. Design
The payload must have no input power (no-volts) prior to launch. Design, Test
The payload must withstand temperatures up to 100F. Analysis, Test
The payload must withstand forces up to 25Gs. Analysis, Test
The payload electronics must be properly harnessed and staked. Design
The payload must pass the DITL test. Design, Test
The payload must be capable of meeting all mission objectives. Design, Test
8
Compliant
Partially Compliant
Functional Block Diagram 9V Li Ion Batteries
RBF Wiring
G-Switch
Voltage Regulator
3.3V 5V
Flash memory
ADC Data
Microprocessor
XL, YL, XH, YH, ZL, ZH Accelerometers
Data out
Vcc VL
Logic Level Translation Data
In
ISP (Data
retrieve)
Level Shifter
Data Analysis
Coding Micro
PC ISP
(Programming code )
9V 5V 3.3V Data
Legend
9
Structural Drawings
10
Plate Mounting Inside Canister
Expanded View Of Plates Passively Damped System
Rigidly Mounted System
Structural Drawings
Plate Details
11
Gel Mounts
Springs
G-Switch
G-Switch
9 V Batteries
9 V Batteries
Main Board
Main Board Z Accelerometers
Z Accelerometers
RockSat Canister
Shared Can Logistics Plan
Canister Being Shared With West Virginia University And Louisiana University Communications Through Email And
Teleconference We Will Occupy The Top Half Of The
Canister All Structural Diagrams Will Be
Drawn On Solid Works Allows For Center Of Gravity Simulation
12
Subsystem Requirements
Structure Vibration Isolation System Power Mass Sensors And PCBs Command And Data Handling States
14
Subsystem Requirements
Structure Two Plates Containing Identical
Electronic Equipment On Each Integrate Into Canister Using Support
Brackets From RockOn Workshop
15
Subsystem Requirements
Vibration Isolation System Passive Isolation System Maximum Vibration Isolation Ratio
Desired Selection Between Three Designs To Be
Decided Upon After Shock And Vibration Testing On Shaker Tables
17
Design Concept 1
18
Silicone Gel Mounts Designed For
Isolating Printed Circuit Boards
Offers Shock And Vibration Damping
Design Concept 2
19
Spring Damping System o Board Will Be
Suspended Between Springs To Dampen Motion In All Directions
Casing
Springs Printed Circuit Board
20
Design Concept 3 Hybrid-
Spring & Gel Mounts The PCB Is
Mounted On A Hexagonal Plate With The Gel Mounts And Springs Integrated
Gel mounts Top view
Side view
Springs PCB
Casing
Subsystem Requirements
Power (For Each Identical System) Two 9V Lithium Ion Batteries
Connected In Parallel Provides Continuous Power
Throughout Entire Flight Voltage Regulators Will Step
Voltage Down To 5 And 3.3V
21
Subsystem Requirements Power For Each Identical System
Major Power Consumption Parts Voltage (V)
Current (mA) Power
AVR Microcontroller 3.3 12 39.6mW Low Range X & Y Axis Accelerometer 5 1.1 5.5mW Low Range Z-axis Accelerometer 5 1.1 5.5mW High Range X &Y Axis Accelerometer 5 2.9 14.5mW High Range Z-axis Accelerometer 5 2 10mW Flash Memory 3.3 20 66mW Logic Voltage Shifter (VL side) 3.3 0.13 0.429mW Logic Voltage Shifter (Vcc side) 5 0.016 0.08mW
Total Power Consumed 141.61 mW Total Energy Requirement (Entire Flight Takes About 25mins) 211.5 J
Power That Batteries Are Able To Supply (Able To Supply More Than 1 Hour)
270mW
22
Subsystem Requirements Mass
Part Mass (lbm) QTY Total Mass (lbm)
3/16’’ Polycarbonate Plates 0.550 2 1.100 Spacing Standoff (0.25’’) 0.004 5 0.020 Female-Male Standoff (1.5”) 0.015 20 0.300 Two 9V Batteries With Bracket 0.180 2 0.360 G-switch 0.010 2 0.010 PCB With Components Assembled (Est.)
0.200 2 0.400
Silicone Gel Mount (Est.) 0.010 8 0.080 Springs (Est.) 0.005 10 0.050 Plate Used To Attach Spring System (Est.)
0.200 1 0.200
Total Mass Of Designed System (lbm) 2.52
23
Subsystem Requirements
Sensors Two Identical Vibration Measurement
Systems ○ Dual Axis, Low And High Precision
Accelerometers For X And Y Direction ○ Single Axis, Low And High Precision
Accelerometers For Z Direction
24
Sensor Specs X & Y Axis Accelerometer (5mm X 5mm X
2mm) High g ○ AD22284-A-R2CT-ND ○ It Is A Dual Axis Accelerometer Available In +/-
35 g Output Full-scale Ranges ○ Accuracy: 0.2% Of Full Scale
Low g ○ ADXL203 ○ It Is A Dual Axis High Sensitive Accelerometer
Available In +/-1.7 g Output Full-scale Ranges ○ Resolution: 1 mg At 60Hz
25
Sensor Specs
Z Axis Accelerometer (5mm X 5mm X 2mm) High g ○ AD22279-A-R2CT-ND ○ It Is A Single Axis Accelerometer Available In +/-
35g Full-scale Ranges ○ Accuracy: 0.2% Of Full Scale
Low g ○ ADXL103CE ○ It Is A Single Axis High Sensitive Accelerometer
Available In +/-1.7g Full-scale Ranges ○ Resolution: 1mg At 60Hz
26
Subsystem Requirements
Command And Data Handling Will Utilize Onboard Flash Memory For
Data Storage Microprocessor Will Utilize C
Programming To Handle Data Code Must Accommodate Complete
Data Flow For Entire Flight Adapted From RockOn Workshop
27
Command And Data Handling
Rough Outline Of Code Flow
Initialize Systems
• Initialize ADC • Initialize Flash Memory • Initialize Timer
Check Board Connectivity
• Check Microprocessor Connection
Write Sensor Data
• Write Converted Data To Flash Memory
Sample Sensors
• Wait For Analog Data From Sensors • Convert To Digital Data
28
Data Storage Overview
29
Analog Data (Sensors)
Data Flash 16Mbits =
2MB
ADC
Microprocessor
Memory Buffer
Write
Memory Dump (PC)
Memory Flush
States
Prior To Rocket Launch, System Will Be Idle
Upon Rocket Launch, The G-switch Will Activate The System And System Will Be Active For Entire Flight
30
Parts List
31
Parts Manufacturer Model No. Quantity AVR Microcontroller Atmel ATMega32-16PU 2 9V Flight Battery(Lithium)
Ultralife U9VL-J 4
Low range Accelerometer(x,y)
Analog Devices ADXL203CE 4
Low range Accelerometer (Z)
Analog Devices ADXL103CE 2
High range Accelerometer(x,y)
Analog Devices AD22284-A-R2CT-ND 4
High range Accelerometer(z)
Analog Devices AD22279-A-R2CT-ND 2
Flash Memory Altmel AT26DF161A 2 G-Switch Digikey SW156-ND 2 5V Voltage Regulator Texas Instruments LM2937IMP-5.0CT-ND 2
3.3 V voltage Regulator
Texas Instruments LM2937IMP-3.3CT-ND 2
RockSat Canister Compliance Type of Restriction Restriction Status
Mass allotment: Half the canister ~ 6.5bs (~2.94kg).
Volume allotment: Half the canister diameter of 9.3” and a height of 4.7”
The payload’s center of gravity (CG): 1”X1”X1” envelope of centroid
Wallops No-Volt Requirement Compliance: RBF wires and G-Switch
Yes
Structure mounts: five (5) bottom bulkheads and five (5) top bulkheads
Top and bottom bulkheads. No mounts
to sides of cans.
Sharing: West Virginia and Louisiana Top Half
32
Compliant
Partially Compliant
33
Design And Testing Process Design Sensing Circuits
• Schematic • Coding • Placement On Plate
Acquire Materials (Sensing Circuits)
• Accelerometers, Microprocessors, Flash Memory, Etc.
Assemble Design
• Sensing Circuitry With Passive System
Design Passive System
• Concept 1 • Concept 2 • Concept 3
Test Design
• Meets Specifications And Requirements • Vibration Damping • Data Acquisition
Acquire Materials (Passive System)
• Silicone Gel Mounts • Springs
Results
• Memory dump • Quantify
Test Other Concepts And Compare Performances
33
Test Plans Vibrations
Test Vibration Damping Designs Using In-House Shaker Tables (3 Design Concepts)
Coding Withstand Vibration Environment Verify Programming Codes Verify Accurate Data Acquisition After
Exposure To Shaker Table ○ Compare Data Of Undamped Board Vs.
Damped Board
34
Test Plans Heat Test
Payload Must Withstand ~100 ° F Circuitry
Test RBF Wires And G-Switch Multimeter ○ Verify Power Levels ○ Continuity ○ Verify System Compatibility
Center of Gravity Within Specified Region
35
Safety Update
Meet Requirements Of RockSat Payload Canister User’s Guide Ensure RBF Compliance ○ RBF Compliance Has Been Implemented In
Schematics ○ G-Switch Activation Has Been
Implemented In Schematics Ensure CG Compliance ○ Working With The Universities Within Our
Canister To Ensure 1x1x1 in. CG
37
Timeline
38
RockSat 2010 Task/Item
11/1
3
11/2
0
1/22
1/29
2/5
2/12
2/19
2/26
3/5
3/12
3/19
3/26
4/2
4/9
4/16
4/23
4/30
5/7
5/14
5/21
5/28
6/4
6/11
6/18
6/25
CDR Due CDR Teleconference Subsystem Testing
Damping Systems Testing
Subsystem Report Due
Subsystem Teleconference
Subsystem And Damping System Assembly
Subsystem Integration And Testing Report Due
Subsystem Integration And Testing Teleconference
Prepare Full Mission Simulation
Weekly Teleconference First Mission Simulation Report
Due Weekly Teleconference Weekly Teleconference Weekly Teleconference Weekly Teleconference
Second Mission Simulation Report Due
Weekly Teleconference Launch Readiness
Teleconference Weekly Teleconference Integration At Wallops
Launch
Management
39
Part Cost Half Of Canister $7000
Accelerometers (x8) $80
Microprocessor $80
Gel Mounts $150
Springs TBD PCB TBD
Total Cost Approx. $7700
Budget
Payload Design Requirements
Altitude ≈ 115 km
Spin Rate ≈ 1.3 Hz at Terrier Burnout ≈ 4.8 Hz at Orion Burnout
Max Gravity 25 G With Possible Impulses at 50 G In Z-Axis +/- 10 G in X & Y Direction
Dimensions Diameter = 9.3 Inches Height = 4.75 Inches (Our Half) Center of Gravity = 1 Cubic Inch of Canister’s Centroid
Mass Canister + Payload = 9.07 kg ≈ 20 lbs.
43