U.S. NAVAL ACADEMY SpaceGoat Critical Design Review · U.S. NAVAL ACADEMY Mission Statement...

U.S. NAVAL ACADEMY

SpaceGoat Critical Design Review

Dillon Pierce, Arthur Sakamoto, Michael Simpson

30 November 2012

U.S. NAVAL ACADEMY

Mission Overview Dillon Pierce

11/30/2012 U.S Naval Academy 2

U.S. NAVAL ACADEMY Mission Statement


• Accurately model spacecraft launch vibrations to develop more accurate shake test profiles

• Goal is to reduce current shake requirements in order to minimize structural weight and mission costs.

• Characterize a more realistic safety factor for shake tests

• Incorporate variable strength material to accurately determine structural stress during a launch by intentionally inducing failure

U.S. NAVAL ACADEMY Mission Requirements

• Determine effects of vibrations on materials during launch vibrations and G load

• The goal is to reduce current shake requirements in order to minimize structural weight and mission costs

• We hope to characterize a more realistic safety factor

• Our plan is to incorporate variable strength material to accurately determine structural stress 11/30/2012 U.S Naval Academy 4

U.S. NAVAL ACADEMY Theory and Concepts

• The vibrations will be maximized during the initial launch as well as during the firing of the second stage.

• The expected G-Force will be largest during the initial part of both stage launches and constant during the rest of the launch

• The structural failure will be greater during the second stage firing but will still be less than shake test requirements


U.S. NAVAL ACADEMY Concept of Operations

• Pre-Flight – Survive shake test – Shall conform to RockSat design

constraints • Terrier Burn (0-5.2s)

– Turn on – Timed measure of G-Force, vibration,

and structural stress – Store measurements taken from sensors

• First Coast Stage (5.2-15s) – Distinguish between first set of data – Timed measure of G-Force, vibration,


• Orion Burn (15-40.4s) – Distinguish between previous data – Timed measure of G-Force, vibration,


• Second Coast Stage (40.4-489.2s) – Distinguish between previous data – Timed measure of G-Force, vibration,


• Chute Deployment (489.2-550s) – Store data in distinct stages for clear

delineation – Prepare for water landing – Power off system


Preflight

Terrier Burn (0-5.2s)

First Coast Stage (5.2-15s)

Orion Burn (15-40.4s)

Second Coast Stage (40.4-489.2s)

Chute Deployment (489.2-550s)

U.S. NAVAL ACADEMY Data Resolution


-10

-5

0

5

10

15

20

25

0.05

1.05

2.05

3.05

4.05

5.05

6.05

7.05

8.05

9.05

10.0

511

.05

12.0

513

.05

14.0

515

.05

16.0

517

.05

18.0

519

.05

20.0

521

.05

22.0

523

.05

24.0

525

.05

26.0

527

.05

28.0

5

G F

orce

Time (s)

X HighY HighZ High

• Wanted a range that would yield some specimens intact and some broken

• Range from 10-26 G’s would be sufficient • A 2 G increment was selected - would provide sufficient resolution

between points • Wider data range allows for possible testing of the second stage data

U.S. NAVAL ACADEMY Mission Overview

8

• Two experimental setups – one breakable, one resettable

Breakable Resettable

Magnet

Laser

Detector

Magnet

Laser

Detector

Current reading

Current reading

TASC Cell

TASC Cell

11/30/2012 U.S Naval Academy

U.S. NAVAL ACADEMY Success Criteria

9

Criteria Optimum Threshold

Breaking of specimens All specimens break at designed loads

Some must break, though not all should break

Acquisition of data All data from all of the sensors is retrieved

Time and force at which samples break is recorded

Correlation of data All data correlates and is clear

The majority of the data agrees

Amount of data Both rocket stages are measured and recorded

The first rocket stage is measured and recorded


U.S. NAVAL ACADEMY

Design Description Arthur H. Sakamoto


U.S. NAVAL ACADEMY De-Scopes and Off-Ramps

• Mission objectives remain the same with contingency for lower data quality.

• Off-Ramps: – 3-D Printing of Test Bed – If we are unable to secure a source of 3-D printing

for our test bed, we have incorporated plans for a machined alternative.

– Decrease samples. – Worst case: Omit resettable test. Decision made

based upon manufacturing considerations.


U.S. NAVAL ACADEMY Mechanical Design Elements

• Base plates made with 6061 Aluminum • Components made with ABS/PC plastic • 2-56 stainless steel fasteners will be used • Overall structure mass (w/o electrical, sensors, etc)

is 3.95 lbs. Estimated total mass: 10.45 • The top plate configuration has not been finalized.

– Electronics will be attached to maintain CG as necessary

– It’s mostly a flat plate w/ some electronic components. • Survivability modeled by Solidworks


U.S. NAVAL ACADEMY System Design – Physical Model

Top plate- Electronics

Bottom plate- Test apparatus


U.S. NAVAL ACADEMY Subsystem Design – (Top Plate)

14

Arduino Processor

Batteries

MUX


SD Card

U.S. NAVAL ACADEMY Bottom Plate

• Bottom Plate is made of four quadrants

• Each quadrant is equal in dimension to the others


Testbox

Laser Stand

Pole hole

U.S. NAVAL ACADEMY Quadrant View


Pole hole

Testbox

Laser Stand

U.S. NAVAL ACADEMY Testbox


Resettable

Breakable

U.S. NAVAL ACADEMY Testbox (cont)


Breakable Resettable

2-56 screws

U.S. NAVAL ACADEMY Software Design Elements – Flow Chart

19

Start

Analog Read

Power on camera

Yes

No

Print annotated Data

Laser On

Laser off

Power on Laser

Under Load?

Rec. Photo Data?

Yes Yes

No

Print Data

Read Current

Capture Image

Store Image

Rec. Data?

Print Data Annotate last data point

No

End

U.S. NAVAL ACADEMY Example Code


Read of serial output

Conditional Statement

Digital write command

Print Command

Assign output

U.S. NAVAL ACADEMY Major Program Functions

• Print() – Prints data to the serial port as human-readable ASCII

text • Serial.begin

– Sets the bits per second (baud rate) for incoming serial data

• digitalWrite – Outputs a value of HIGH or LOW for a pin assignment

• analogRead – Allows Arduino to read the values from the analog

inputs (photoreceptor, current meter, etc.) 11/30/2012 U.S Naval Academy 21

U.S. NAVAL ACADEMY Initial Prototyping of Software


U.S. NAVAL ACADEMY Breakable Design Prototyping


Known mass to get spring constant

Measured displacement in order to get force to break the cells

U.S. NAVAL ACADEMY

Prototyping/Analysis Michael Simpson


U.S. NAVAL ACADEMY Mechanical Analysis Results

• Solidworks used to analyze structure – Used to ensure no errors in dimensions

encountered. – Ability to analyze stress, deflection, etc. – Overall integrity is maintained. – Ease of communicating intent/transferring files.

U.S. NAVAL ACADEMY Detailed Mass Budget

• Final Mass Budget will be calculated upon receiving parts.


ExampleSat Mass Budget Subsystem Total Mass (lbf)

Sensors 1 (TBR) Half-Container 4 (TBR) Arduino 1 (TBR) Structure 3.95 Test specimen 0.5 (TBR)

… Total 10.45 (TBR) Over/Under 0.45

U.S. NAVAL ACADEMY Electrical Analysis Results

• The Electrical system has been analyzed to ensure that there is enough power supplied to each component

• The Arduino/Multiplexor has been verified to be able to handle all the inputs and properly store them in the data storage

U.S. NAVAL ACADEMY Detailed Power Budget

• Final amperage to be refined upon receipt of components

U.S. NAVAL ACADEMY Prototyping Results

• The electrical system is being prototyped on multiple diagrams so it can be fully understood

• The test plate CAD is completed • They have not been fully tested so we are

unable to use the results to make adjustments for the final mock up

U.S. NAVAL ACADEMY

Manufacturing Plan Arthur Sakamoto


U.S. NAVAL ACADEMY Mechanical Elements

• Manufacture: – Test apparatuses, structure – Will use in house manufacturing (timeline limited) – Estimated manufacture completion date of

11DEC12 – Alternate: Potential 3D printing (cost limited)

• Procurement: – Test specimens – Fasteners (screws) – Most parts have been ordered


U.S. NAVAL ACADEMY Electrical Elements

• Manufacture: – Connections will be soldered to ensure connectivity

(including SD card) • Procurement:

– Printed circuit – Electrical components

• Timeline: – Parts have been ordered


U.S. NAVAL ACADEMY

Testing Plan Arthur Sakamoto


U.S. NAVAL ACADEMY

• Majority of code must be written to test electrical subsystems

• Items we should see from individual subsystems tests on following slides

Software Testing


U.S. NAVAL ACADEMY

Resettable Design - Software Test Outcomes


• Laser On, Arduino receiving data from photo-receptor

• Photo-receptor blocked, Arduino no longer receiving data

• Arduino commands laser to turn off

• Arduino turns laser on when not under load

Reading

Reading

No Reading

No Reading

U.S. NAVAL ACADEMY

Resettable Design-Sensor Threshold Test

• Lighting tests – Ensure ambient light does not affect resettable test – Must set photoresistor so there is a noticeable

difference between the laser being broken – Will be completed prior to integration of sensor

with system


U.S. NAVAL ACADEMY

Breakable Design - Software Test Outcomes


Current reading

Current reading

• Arduino is receiving continuity reading from TASC cell

• Once the continuity is discontinuous – the Arduino puts a “flag” in the data

U.S. NAVAL ACADEMY Camera - Software Test Outcomes


SD Card

• Camera must be able to capture images and successfully write them to the SD Card

• Images must be recoverable from SD Card

SD Card

U.S. NAVAL ACADEMY

Resettable Design – Mechanical Test Outcomes

• Testing will be done up to 25 g’s with focus in critical load regimes

• Success: Magnet separates at designed load and vibration

• Testing will begin upon acquisition of materials


U.S. NAVAL ACADEMY

Breakable Design – Mechanical Test Outcomes

• Testing will be done up to 25 g’s with focus in critical load regimes

• Success: Specimen breaks at design loads • Testing will begin upon acquisition of materials


U.S. NAVAL ACADEMY

Non Structural Components-Mechanical Test Outcomes

• Ensure survivability of non-structural components

• Ensure functionality of non-structural components in potential load regimes

• Will be completed upon receiving materials


U.S. NAVAL ACADEMY Testing Plan


Component manufactured

Function?

Survive? Redesign component

Component integration

Survive?

Function?

Redesign system

Payload integration

Survive?

Function?

Redesign payload

• Red- Component testing • Yellow- Component integration into

system and system testing • Green- Overall payload integration

and testing • Survive- Does not fail under test loads • Function- Functions properly in tests • Testing will be shake tests done

according to predicted loads

Yes

Yes Yes

Yes

Yes Yes

No

No

No

No

No

No

Yes

Yes

U.S. NAVAL ACADEMY

Risks Michael Simpson


U.S. NAVAL ACADEMY Risk Walk Down

EPS.RSK.1: Data collection fails in-flight, and the mission objectives are not met. EPS.RSK.2: Data collection material cannot be procured to meet mission objectives. EPS.RSK.3: The data collection methods cannot survive initial launch conditions, and the mission objectives are not met. EPS.RSK.4: Proper data collection fails during launch.

U.S. NAVAL ACADEMY Risk Walk Down

• We do not have any new risks since the PDR • Biggest risks during flight are the failure to

document, store or retrieve data • We are looking at connections and electrical

isolations to ensure that data collection is not compromised and data is protected during and after flight

• There will be risks in flight of improper or non collection of data. We can take as many measures as possible but there is always a chance

U.S. NAVAL ACADEMY Resettable Material Testing

• The vibrational and G-Force application needs to be tested on the Resettable material

• This will be done using our own equipment • The system will be deemed passing if the

material “breaks” at the proper loading and resets during the coast phase

• This tests will be performed once the mockup has been completed

U.S. NAVAL ACADEMY Breakable Material Testing

• The vibrational and G-Force application needs to be tested on the Breakable material

• This will be done using our own equipment • The system will be deemed passing if the

material breaks but still provides continuity to determine how much breakage has occurred

• This tests will be performed once the mockup has been completed

U.S. NAVAL ACADEMY Vibrational/G-Force Testing

• The vibrational/G-Force will be measured during the entire flight using accelerometers

• We will test the measuring capabilities using our own equipment

• The system will be deemed passing when it can accurately measure the force applied to the can

• This test will be performed when the mockup has been completed

U.S. NAVAL ACADEMY Video Feed Testing

• The video feed is required to take footage of the flight to show actual breakage to be used in comparison to data captured

• It will be tested during the shake test to ensure that it will be able to capture visible data

• The system will be deemed passing when it can accurately capture the data and store it

U.S. NAVAL ACADEMY Data Processing Testing

• The data processing and storage will be tested in and out of the shake test to ensure that it can take the data and store it properly under both conditions

• We will ensure that the Arduino and multiplexor can capture the required amount of data and store it to be viewed later

• The system will be deemed passing when it can take all the inputs within the required time and accurately store them in the correct location to be viewed later

U.S. NAVAL ACADEMY Power Testing

• The power system is required to provide ample (twice mission duration) power to all the systems during the duration of the flight to ensure data capture and storage

• We will test the system to make sure that it can provide enough power during the flight

• The system will be deemed passing when it lasts for the length of time that is considered the duration of flight

U.S. NAVAL ACADEMY Electrical Diagram

U.S. NAVAL ACADEMY Electrical Diagram Top Plate


U.S. NAVAL ACADEMY Electrical Diagram Bottom Plate


U.S. NAVAL ACADEMY

User Guide Compliance Arthur Sakamoto


U.S. NAVAL ACADEMY User Guide Compliance

• Overall mass: Dependent upon receiving materials (but we will be within specification)

• CG: Will be centered. Ballast, flexibility in arrangement of top plates ensures this requirement – Initial analysis (Solidworks) shows main CG factor

is in longitudinal direction • No rechargeable batteries will be used • No ports or high voltage required • Early activation will be used 11/30/2012 U.S Naval Academy 57

U.S. NAVAL ACADEMY Shared Can Logistics

• Sharing with Temple • Temple’s mission is: Collecting samples of the

troposphere, stratosphere, and stratopause • Telephones, email used to communicate • Will meet in person to conduct fit tests once

manufacture is completed • Structural interface will be done using standoffs


U.S. NAVAL ACADEMY

Project Management Plan Dillon Pierce


U.S. NAVAL ACADEMY

SpaceGoat 13

26OCT12-Preliminary Design

Review

Identify Key Components and

Parts

Determine lead time of key components

Complete Interface Control

Document

Design Test Plan

Detailed subsystem design

16NOV12-Critical Design Review

Generate parts list

Complete integration and

test plan

Publish manufacturing

documents

Develop complete physical mockup

15FEB13-Individual

Subsystem Testing Reports

Procure parts

Build Subsystems

Test Subsystem functionality

Ensure subsystems fulfill

mission requirements

29MAR13-Payload Subsystem

Integration and Testing Report

Integrate Subsystems

Ensure mission requirements

fulfilled

Test sub-assemblies

26APR13-Full Mission

Simulation Test Report

Test fully integrated system

assembly

Run Mission Profile Simulation

Make adjustments as necessary

12JUN13-Travel to

Wallops

Create checklist

Clear action items

Prepare for launch

Post Flight Analysis

Disassemble and document

Analyze data

Create report

Work Breakdown Structure (Overall)

U.S Naval Academy 60

U.S. NAVAL ACADEMY First Semester Schedule


Preliminary Schedule for RockSat 2012-2013 (By Week) 1 2 3 4 5 6 7 8 9

Corresponding Dates 15 Oct-21 Oct

22 Oct-28 Oct

29 Oct-4 Nov

5 Nov-11 Nov

12 Nov-18 Nov

19 Nov-25 Nov

26 Nov-2 Dec

3 Dec-9 Dec

10 Dec-16 Dec

Order Parts Complete Integration and Test Plan Publish Manufacturing Documents Begin Thanksgiving Break Begin Final Examinations and Christmas Leave Critical Design Review (CDR) Due 11/30 Submit CAD Model for Manufacturing of Bottom Plate Complete Electrical System Diagram Complete Code for Arduino Test Arduino Code Develop Complete Test Model - Breakable and Resettable

U.S. NAVAL ACADEMY Budget


Registration Fee $ 7,000 Materials $ 1,000

Electrical Components $ 1,000 Machining and Fabrication $ 0

Travel $ 4,000

Total (no margin) $ 13,000 Budget $ 13,000

U.S. NAVAL ACADEMY Parts List

11/30/2012 63

Item Description Part Number Supplier Unit Price Quantity Total Price Shipping Cost Status

SD Card 2 GB SD 115x Memory Card DDSDFLSI-2GB Delkin 5.99 1 5.99 6.75 Breakout Board Breakout Board for SD-MMC Cards BOB-11403 SparkFun 9.95 1 9.95 4.13

Servo Motor HS-805BB Giant Scale Servo Motor RB-Hit-32 RobotShop 39.99 1 39.99 6.42 Shielding Foil Magnetic Shielding Foil (4.5in x .004in) Cat. # A276-4.5 LessEMF 6.00 5 30.00 9.50

Microcontroller Arduino Mega 2560 REV 3 Catalog #: 276-127 Radio Shack 64.99 0 0.00 0.00

Camera TTL Serial JPEG Camera with NTSC

Video ID: 397 Adadfruit 42.00 0 0.00 0.00 Laser Focusable Laser Module with Plans AK1894BB Amazing1 19.95 8 159.60 17.50

Magnets Channel Bar Magnets — Grade 5 5695K14 McMaster 34.70 8 277.60 5.00 Accelerometers Dual Axis Accelerometer 37G AD22284-A-R2 Newark 12.35 5 61.75 4.13

Multiplexor Mux Shield DEV-09832 SparkFun 24.95 1 24.95 3.81 Photo Receptor Mini Photocell SEN-09088 SparkFun 1.50 8 12.00 4.13

Epoxy Quick-Setting Steel Reinforced Epoxy J-B Weld 8276

Kwik Amazon 6.03 4 24.12 5.74 LEDs Diffused LED COM-10632 SparkFun 0.50 20 10.00 4.13

Syringe Dispensing Syringes - 12 Pack 807-12 West Marine 19.99 1 19.99 9.95 TASC Triangular Advanced Solar Cell SpectroLab - 8 -

Total Cost (No Shipping): 675.94 Total Cost (W/Shipping): 757.13

Cost w/10% Margin: 743.53 Cost w/10% Margin w/shipping: 832.84

U.S. NAVAL ACADEMY Success Criteria

64

Criteria Optimum Threshold

Breaking of specimens Half of the specimens break and half do not

At least one specimen breaks and one does not

Acquisition of data All data from all of the sensors is retrieved

Time and force at which samples break is recorded

Correlation of data All data correlates and is clear

The majority of the data agrees

Amount of data Both rocket stages are measured and recorded

The first rocket stage is measured and recorded


U.S. NAVAL ACADEMY Future Work


• Ordering and manufacturing final parts

• Begin manufacturing • Completed breakable and resettable

test specimen – end of semester

U.S. NAVAL ACADEMY Conclusion

• We are confident we will meet mission requirements – Design is finalized

• Main concern is receiving parts/manufactured components on time – Long manufacturing lead time


U.S. NAVAL ACADEMY SpaceGoat Critical Design Review · U.S. NAVAL ACADEMY Mission Statement...

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Transcript of U.S. NAVAL ACADEMY SpaceGoat Critical Design Review · U.S. NAVAL ACADEMY Mission Statement...