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Micro Meteoroid Impact Detection

Team Members: Matt Arnone, Nick Harris, Matt Hinkelman, Jay Hirata, Matt Mihelish, and Alex Swanson

Mentor: Greg SwansonAdvisor: Jay McCormack

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Problem Description

NASA has commissioned Team Impact to analyze how an electronic hit indicator (EHI) will react to a micro meteoroid/orbital debris (MMOD) impact. This involves creating a test fixture that will hold the EHI during high-speed testing, a high-speed data acquisition system, a graphical user interface, and a computer model of the impact.

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Summary of Project Learning

Each member was assigned an area of study and then created a small report to share with the group.

Alex Swanson – Test fixture Matt Mihelish – Orion research Jay Hirata – Past uses/Explorer 16 Matt Hinkelman – FEA Nick Harris – Computer interface Matt Arnone – FPGA/μC

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Summary of Specifications

SYSTEM GENERAL SPECIFICATION

Test fixture •Flexibility•Ease of use•Accuracy•Durability•Load/Force measurements

ECE •Plug and Play•High speed data acquisition•Grid flexibility•Data transfer

GUI •Display hit location•Display impact logs•Export test logs

FEA •Simulate test results•Display results in easy to read format

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Test Fixture Design

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Design Features

Steel backing plate Steel guide rods PVC clamping plates EHI Gasket Steel collar with set screws Replaceable TPS backing

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Collar Close-up

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Back Plate Close-up

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Defined Edges View

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Previous Design ChoicesDesign Pros CONS

Linear bearings Smooth rod movement

Too expensive and unnecessary

Steel clamping plates

High strength Too expensive,would not survive high speed impact

Acme screw Precision adjustment of length

Difficult to integrate with PVC clamping plates

“Slot” length adjustment

Quick an easy to set an accurate length

Would not allow for varying TPS thicknesses

Replaceable steel back plates

High strength, quick to replace

Expensive, would not integrate well with strain gages

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Test Fixture Budget

Materials Cost : $123.61

Shipping Cost: $24.72

Supplier: McMaster-Carr Online

Total Test Fixture Budget: $148.33

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ECE Design Choices

Function Options

Processing FPGA Microcontroller

GUI Web Based Windows/Linux LED

Storage On-Board Streaming

Data Transfer USB RS-232 Ethernet

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ECE Design Choices

FPGAs were chosen because of their extended I/O support.

Web based programming languages were chosen because they are inherently graphical.

On-board storage was chosen to avoid real time data transfer to a PC.

USB was chosen due to its universality.

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Top Level Hardware Block Diagram Describes the interface between

physical hardware components which will be incorporated into the design.

The system will operate at 50MHz creating a detailed log file which will be transferred via USB to the PC to be sorted and viewed.

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Top Level Hardware Block Diagram

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FPGA Internals Block Diagram The FPGA will be designed with a 40-bit

counter, allowing for up to ~6 hours between tests to provide unique time stamps for the impacts.

Data will be temporarily stored until transfer via USB in the FIFO (First In First Out) elastic buffer.

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FPGA Internals Block Diagram

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Simulation

The data is presented to the pins of the FPGA.

The output of the memory element presents a “data_available” flag.

The output data is equal to the input data and it changes each time “rd_data” is high, (when the clock rises).

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Simulation

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GUI Prototype

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ECE Prototype Budget

Current ExpendituresFPGA Project Board: $0 (Jim Frenzel)USB Accessory Board: $47.95 (Digilent)3-Way Connectors: $8.95x3 = $26.85 (Digilent)Resistors: $0 (Greg Swanson)Wires: $0 (Greg Swanson)34-Pin Cables: $0.99x6 = $5.94 (Newegg.com)

Total prototyping costs: $80.74 + tax & shipping

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Prototype Board Pictures

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ECE Final Design Budget

Final Design CostsCustom PCB: ~ $200x2 = $400Spartan II FPGA: ~ $50x2 = $100Misc: ~$75x2 = $150

Total final design costs: ~$650 Total projected ECE design costs: Final

Design Costs + Prototype Costs ~$730.74

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Finite Element Analysis

Purpose: Accurately simulate test materials and results obtained from impact testing.

Software Options:

Abaqus explicit ($2500)

LS-DYNA Educational Version($500)

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FEA Status

Purchased LS-DYNA• Installation Problems

Abaqus• Installation Problems

Student Version• Spring ‘09 Upgrade

Currently Learning Abaqus• Expected Capabilities

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Budget Review BUDGET: $8,000

FEA program: $500 (already purchased)ECE Prototype: $80.74 ECE Final Design: $650Test Fixture Final Design: $148.33 Travel Expenses: $4,953.00Miscellaneous: $910.00

TOTAL COSTS: $7,079.18.18 REMAINING FUNDS: $420.82

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End of Semester Schedule

November 24-28(Thanksgiving) December 1-5

Finalize 3-D model Begin work on test procedure Finalize first version of GUI Start work on report Create snapshot poster Order test fixture parts Test prototype

December 8-12 Finish report Give initial test procedure to A. Cassell Webpage review Logbook collection

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Second Semester Overview January

Machine and assemble test fixture Purchase airline tickets and hotel Begin work on FEA Model Finish test procedure Design and order data acquisition PCB V.1 Purchase honeycomb and carbon fiber

February Assemble and complete final data acquisition system Design and order data acquisition PCB V.2 (if necessary) Finish GUI program Assemble service module extension material Conduct local testing

March Update fixture, GUI, and data system based on test data Create FEA report summarizing impact behavior Conduct testing in NM (tentatively March 23-27)

April Perform data analysis Begin work on final report

May Finish final report Create poster Final project review

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Potential Problems and Risks

Potential Problem Solution

Flight costs rise Budget surplus of almost $420 will compensate for any unforeseen price increases

Unavailability of test facility

Team Impact can travel to NM 2 separate dates: March 9-13 or March 23-27

Equipment damage Team already plans on purchasing extra materials, PCBs, and FPGAs

Time constraints with learning FEA program

Each ME has a trial version of ABAQUS. Thanksgiving and X-mas breaks will be used to learn software.

Questions