Adam HertzlinDustin Bordonaro

Jake GraySantiago Murcia

Yoem Clara

P14651: Drop Tower for Microgravity Simulation

Project Summary Problem Goals

Design & Build Drop Tower Vacuum Piping Structure Cost Effective Effective Cycle Time Aesthetically Pleasing Precision in Measurements Educational User Interface Access for Object Transfer Adaptability for Future Development

Constraints Location and design approval from the dean(s) Material availability/size (ex. tube, pump) The device is aesthetically pleasing The tower 6” – 12” Diameter The device can be operated year round. The system is safe to operate. The project budget is $3,000. Team must justify the need for additional

funds. The project must be completed in 2 semesters.

Project DeliverablesInstalled drop towerDetailed design drawings and assembly manualBill of materialsUser’s Guide for operationDesigned Lab Experiments

Determine gravity in the vacuum within 1% errorCompare drag at different pressures and drag vs. accelerationAdditional vacuum related experiments

Fun and Educational Experience for Middle School Students

Technical Paper Poster

Week #6 Review Open ItemsWhat are the engineering requirement

values?How is external pressure accounted for?Does Temperature Affect Calculations?

AgendaCustomer Meeting Updates

Customer RequirementsEngineering RequirementsProposed Concept DesignIsolation Valve Cost Analysis

List of experimentsConcept and Architecture DevelopmentSystem Block

Sub-systemsSummary

Risk AssessmentTest PlanBill of Materials

Customer Meeting Notes Account for Pipe Fitting Leaks in calculations

How does Ultimate Pressure change with Leak Rate?Limit design to one tower

Simple PrototypeFit two objects in one tower

Allow for lift mechanismDesign Concepts to Future Tower Development

Go with 6-8 in. Diameter, approx. 10-15 ft. Tall TowerMeasure new location heights

Dr. K LabTalk with Mark Smith about using MSD spaceDoes Ultimate Pressure Effect object drop times

Feather vs. Ball BearingUse only one laser when dropping items to measure gravityKeep the educational aspect in mind

Customer RequirementsCustomer Rqmt. # Importance Description

CR1 9 Appropriate Tower HeightCR2 9 Allow for Adjustable PressureCR3 9 Display Tower PressureCR4 9 Drop 2 objects simultaneouslyCR5 9 Drop objects with no horizontal motionCR6 9 Demonstrate standard local gravity within 1%CR7 9 Display important outputs accuratelyCR8 9 Allow full drop visibility and limit distortionCR9 9 Demonstrate drag vs. pressureCR10 9 Allow objects to be changed outCR11 9 Safe/Intuitive operationCR12 9 Educational and InspiringCR13 3 Display Tower TemperatureCR14 3 Design considers noise and power requirements and limitsCR15 3 Components are properly maintained and storedCR16 3 Aesthetically pleasingCR17 3 Generate object lift mechanism concepts for future MSDCR18 3 Allow for further static experiments

Engineering RequirementsRqmt.

# I Engr. Requirement (metric) Unit of Measure Marginal Value Ideal Value

SR1 9 Measure Relative Object Position ft 0-15 >Tower HeightSR2 9 Measure Relative Object Drop Time sec 0-2  SR3 9 Measure Pressure psi 0-14.7 0 - 14.7SR4 9 Cycle Run Time min 1-10 mins 1 minSR5 9 Pressure Leak Rate Minimized psi / sec 0-? 0SR6 9 Aesthetic Structure with Supports Yes / No Yes YesSR7 9 No Horizontal Motion in 0 - ? 0SR8 9 Tube Collapse Pressure FOS 0-5 5SR9 9 Timing difference of object release millisecond 0 - ? 0SR10 3 Tower Height ft 10-15 15SR11 3 Tower Cross - Section (Diameter) in 6-8 8SR12 3 Pump Flow Rate ft3/min 2-10 10SR13 3 Measure Temperature % Error 0-1 0

SR14 3 Impact Energy Dissipation Method Joule 0-(mmaxvfinal2/2) (mmaxvfinal

2/2)

SR15 3 Air Intake - Tower Pressure Change Rate ft3/min 0 - ? ?SR16 3 Minimal Error in Calculations % error 0 - 1% 0%SR17 3 Aesthetic Data Display Yes / No Yes Yes

SR18 3 Platform for Stationary Experiments in (0.50*ID)-(0.99*ID) (0.99*ID)

Isolation Valve – Cost vs. Time AnalysisTime to Evacuate (min)

No Isolation Valves

Time to Evacuate (min) Isolation

Valves

Price, Single Tower, 2 Isolation

Valves

15ft Tower 40ft Tower 15ft / 40ft Tower 15ft / 40ft Tower

6" Dia.  3.25  8.95  0.86  $4,940.00

8" Dia.  5.72  15.46 1.52 $6,880.00

12" Dia.  12.79 34.25  3.41 $9,984.00

Assumptions: No losses due to connection points, 10 cubic foot per meter pump, 15 micron ultimate pressure, 2ft above & below valves, single tower

Isolation Valves Pros and Cons+

Quicker cycle time The air needed to be

taken out of the pump is independent of tower height Can use less costly pump (Lower pump speed)

- Costly Disrupts view of items

falling Can not alter for a

continuous system in the future

More pipe / pump sections need more parts

More chance of pressure leak

Our Conclusion: Although isolation valves would save a substantial amount of time, the time benefit does not outweigh the cost for the tower height we are considering. At this scale it would be more beneficial to increase the pump size instead.

List of ExperimentsDropping two objects simultaneously Measure Gravity Measure DragBalloon ExpansionMarshmallow ExpansionSound InsulatorPlastic Bottle Compression

Note: The following slides will attempt to justify the required tower pressure and size to complete these experiments

CONCEPT & ARCHITECTURE DEVELOPMENT

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System Block Diagram

Sub-SystemsI. Release Mechanism

I. Release system CalculationsII. Air Control

I. Ultimate Pressure II. Evacuation time III. Leak Rate Analysis

III. Catching MechanismI. Energy dissipation Calculations

IV. Piping systemI. Critical external Pressure

V. SensorsVI. Structure

I. Tower height calculationsII. Support Buckling

Engineering Analysis Release Mechanism

Base Specifications

1.5” 1.5”

0.375”

4.0”

0.375”

6.0”

Polycarbonate • Diameter = 6.0 in• Thickness = 0.375 in • ρ = 1.22 g/cm3 (0.0441 lb/in3)

Hatch Doors • Length = 1.5 in • Width =4.0 in• Thickness = 0.375 in

Electromagnet SpecificationsElectrical Specifications

• 12 VDC• Operating

temperature of -40F to 140F

• Holding Force 4.5lbsPhysical Specifications

• Weight – 0.06lbs• Diameter – 0.75in• Height – 0.62in

Other Specifications• Quick Release

Mechanism

Hinges SpecificationsPhysical Specifications• Height – 3.5in• Width – 1.5in• Depth – 0.21in• Radius – 5/16in (0.3125in)Pin Specifications• Length – 3.5in• Radius – 9/16in (0.5625in)

FBD

Given ValuesSymbol Value Units

Wo 32.17 Lbf

Wd 3.19 Lbf

Wm 2.90 Lbf

Fmx 6 Lbf

Equations 

   

  

Force of Magnet in y-direction 

 

 

 

Force of Pin in the x and y Direction

 

Shear Stress

 

 

Factor of Safety

  

 

Engineering Analysis - Air Control Ultimate Pressure & Gravity Error Effect

Gravity Calculation with 1% ErrorConstant Acceleration Equations

Assumes no air resistance / perfect vacuum

, where x is position and t is time

Assume 0.XX% Error due to pressure

Free Body Diagram of ObjectForce Balance

At Terminal VelocityAcceleration = 0

At Vacuum Pressure, drag force = 0, where a is downward (negative)

Drag Force (Air Resistance)

FD = Drag Force ρ = Air Density V = Velocity of Object CD = Drag Coefficient (Fudge Factor) A = Projected Area of Object

P = Air Pressure (Pa) R = Specific Gas Constant = 287.05 J/kg*K T = Air Temperature = 21°C = 274K

Objects to calculate gravity Based on a certain vacuum pressure and other

parameters, center objects will be suitable of calculations while others are not

Objects vary by their mass, projected area and drag coefficient

Assumptions: Allowable Error in Gravity due to Pressure = 0.01%

This can increase if the error from the position and time measurements are minimized

Pressure = 0.015 Torr = 2 Pa This can be decreased if a more efficient pump is available (cost / benefit)

Max Tube Height = 5 meters Max Velocity Ideal Gas Room Temperature Standard Gravity

ResultsFor the assumptions: Gravity Error = 0.01%

Base Pressure = 2 Pam/(CD*A) >= 1.19 kg/m^2

Where: m = mass (kg) CD = Drag Coefficient A = Projected Area

Note: Error % and Pressure can be adjusted to change this threshold

1" Steel Ball

1.625" Steel Ball

Ping Pong Ball Feather Coffee Filter

Drag Coefficient, CD 0.47 0.47 0.47 1.00 0.75

Projected Area, A (m^2) 0.0005 0.0013 0.0013 0.0026 0.0127

Mass, m (kg) 0.067 0.289 0.003 0.001 0.001

m/(CD*A) 280.46 459.63 4.62 0.39 0.14

0 20 40 60 80 100 1200.00

5.00

10.00

15.00

20.00

25.00

30.00

Object Parameter Limit  Based on Ultimate Pressure & Error in Gravity 

0.01% Error0.05% Error0.10% Error

Ultimate Pressure (Pa)

m/(CD

*A)

Ping Pong Ball Threshold

Engineering Analysis - Air Control Evacuation Time

Conductance The flow of air in a tube, at constant temperature, is

dependent on the pressure drop as well as the cross sectional geometry.

Viscous Flow: Pressure (micron) * Diameter (in) > 200

Transitional Flow: 6.0 < Pressure (micron) * Diameter (in) < 200 ,

Molecular Flow: Pressure (micron) * Diameter (in) < 6.0C = Conductance (cfm)

F1 = Viscous/Transitional Flow Scale Factor = 0.52 F2 = Transitional Flow Scale Factor = 12.2 F3 = Molecular Flow Scale Factor = 13.6 D = Pipe Diameter (in) L = Pipe Length (ft)

Viscous Molecular

Equivalent Pipe LengthPipe fittings can cause losses within a

piping systemThese include: elbows, tees, couplings,

valves, diameters changes, etc.Tabulated values for Le/D can be used to

adjust L in the conductance equationsD = Diameter of PipeLe = Equivalent LengthTotal Length = L + Le1 + Le2 + Le3 + ….

Effective Pump Speed SEff for each flow regime

Viscous, Transitional, & Molecularn = number of pipe diametersC = Conductance (cfm) = Given Pump Speed (cfm)= Effective Pump Speed for Tube Dimensions

Evacuation Time = 760 Torr (Atmospheric) = Viscous–Transitional Pressure = Transitional-Molecular Pressure = Ultimate Pressure

• Example: Single 6” x 15’ Tube

Pump used on leftSee Spreadsheet for:

• Fittings• Individual conductance• Individual flow regime time

VP6D CPS Vacuum Pump

2 Stage Rotary Pump15 micron Ultimate

VacuumPump Speed – 6.25 cfm

Price: $268.92

ResultsFor the tube and pump size listed, the evacuation time is 5.25 minutesThis will increase if:

Tube diameter increasesTube length increasesPump speed decreasesUltimate pressure decreases

Engineering Analysis - Air Control Leak Rate

Chamber Leak RateThroughput, Q

Units: (Pressure * Volume) / TimePump Throughput, QP

Where: Seff = Effective Pump Speed P = Pressure

Leak Throughput, QL

Where: dP/dt = Differential Pressure V = Chamber Volume

Constants:• Chamber Volume• Temperature• Atmospheric

Pressure• Leak Area

Time Variables:• Mass Flow Rate• Chamber Pressure

Leak

Pump

𝑄𝑃=𝑆𝐸𝑓𝑓 ∗𝑃

V

𝑃 𝐵𝑎𝑠𝑒=

Δ 𝑃Δ𝑡 ∗𝑉

𝑆𝑒𝑓𝑓

0.0 10.0 20.0 30.0 40.0 50.0 60.00.00

5.00

10.00

15.00

20.00

25.00

30.00

How Leakage Affects Ultimate Pressure 

Leak Rate (Pa / min)

Base Pressure (Pa)

𝑃𝑈𝑙𝑡𝑖𝑚𝑎𝑡𝑒=2𝑃𝑎=𝑃𝑚𝑖𝑛

Flow Regime Change

Engineering Analysis - Catching Mechanism Energy Dissipation

Energy Dissipation

In process …

Engineering Analysis – Piping System Critical External Pressure

Pipe Critical Pressure Calculations

Desired Factor of Safety = 3-4

P  14.7 psiv  0.37 E  429000 psi

Size (in) OD (in) Thickness (in) Max Pressure (psi) Factor of Safety6 6.625 0.28 85.43 5.818 8.625 0.322 57.98 3.94

10 10.75 0.365 43.16 2.9412 12.75 0.406 35.37 2.41

SCH 40 Pipe Maximum Pressure 

Critical Pressure Calculations for Clear PVCFormula

PCrit=(2*E/(1-v^2))*(1/((OD/t)-1)^3)

Pipe Dimensions Courtesy of Engineeringtoolbox.com

Size (in) Max Pressure (psi) Factor of Safety6 90 6.128 58 3.9510 49 3.3312 42 2.86

Max Pressure Rating of Schedule 40 PVC*, from HARVEL

*Specifications for white PVC

Engineering Analysis – Laser SensorSensor

Laser Distance Sensor• Micro-Epsilon ILR-1030• 15m Range• 4-20mA Output• 10ms Response time

Engineering Analysis – StructureTower Height

Free Fall – No Air Resistance (Vacuum Conditions)Applies to All Objects:

Vi=0g=32.2ft/s2

Free Fall –Air Resistance (Atmospheric Conditions)

Fall Time Differs Per Object; Depends on Drag Coefficient, Projected Area and Mass of Object Dropped.

Equations Dependent on Terminal Velocity (Vterm or V∞); The Highest Velocity the Object Reaches, at the Point Downward Acceleration Becomes Zero

Free Fall –Air Resistance (Atmospheric Conditions)

ρ is the Density of Airis the Drag CoefficientA is the Projected Area of the Falling Object

Free Fall –Air Resistance (Atmospheric Conditions)

Tower Height ResultsAssumptions

0.5 – 1.0 drop time difference is adequateSteel Ball Bearing vs. Feather

Result10 – 15ft Tower Height

Engineering Analysis – StructureSupport Buckling

Schematic

• Worst case scenario:– 15’ Long PVC Schedule 40– 8” Diameter– 10’ long square A513 tube

• So 10’ of buckling length

• Assumptions:– Weight of vacuum tube is

split evenly between four connection points

Tube

Frame

Pipe Riser Clamp

Pipe Riser Clamp

Depiction of Reaction Forces on Tube

10ft

W/4

• Becomes an eccentric column loading problem because the weight of the tube is applied on one face of the support columns

• Requires numerical methods root finding techniques

W/4

W/4

W/4

W/2

W/2

Eccentric Distance

Bisection Method using Matlab:function [] = Buckling_Bisection()%Buckling_Bisection finds the value of max applicable load, F, that %the beam may support before collapse. %Calculate tube weight:dens=2.581; %slug/ft^3 http://www.clearpvcpipe.com/pdf/ClearPVCspecs.pdf OD=8.625/12; %OD of pipe in ft (SEE BOM)ID=7.943/12; %ID of pipe in ft (SEE BOM)L=15; %Length of pipe in ftV=(pi()/4)*(OD^2-ID^2)*L; %Volume of pipe in ft^3W=dens*V*32.2; %weight of the pipe in lbfWap=W/4; %weight at each connection point, assuming it's distributed %evenly across two bars with 2 connection points on eact bar %Calculate Pcra=1.5/12; %assuming a square x-section, the width in ftt=.12/12; %thickness of wall in ftb=a-2*t; %inner distace between wallsA=(a*a)-(b*b);l=10; %length in buckling in ftSyc=63100*(12^2); %Yield strength of A513 in lb/ft^3 (MATWEB)E=29700000*(12^2); %Elastic modulus of A513 in lb/ft^3 (MATWEB)e=OD/2+a/2+1/12; %eccentric distance, 1/2 of steel thickness + 1/2 OD of %vacuum tube + distance between edge of steel and vacuum tube c=a/2; %1/2 the distance across the cross-section of the hollow square barI=(1/12)*a*a^3-(1/12)*b*b^3; %Inertia of the bark=sqrt(I/A); %radius of gyrationf=@(F) F/A-Syc/(1+(e*c/k^2)*sec((l/(2*k))*sqrt(F/(A*E))));Fl=1;Fu=10000;Fn=(Fu+Fl)/2;ed=.05;ea=abs((Fu-Fl)/(2*Fn))*100;iter=0;imax=100;while ea>ed && iter<imaxif f(Fl)*f(Fn)<0;Fu=Fn;iter=iter+1;else (f(Fl)*f(Fn))>0;Fl=Fn;iter=iter+1;endFn=(Fu+Fl)/2;ea=abs((Fu-Fl)/(2*Fn))*100;endFr=Fn;FOS=Fr/Wap;%ezplot(f,[1200,2000]); grid minor;fprintf('\n F (lbf) is: %.0f \n FOS is: %.0f \n The percent error is: %.3f \n',Fr,FOS,ea);end

Solution:

>> Buckling_Bisection

F (lbf) is: 1616

FOS is: 84 

The percent error is: 0.038

Parameters:

• 10ft long steel tube

• 1-1/2” square

• 0.120” wall

• A513 steel

False Position Method using Matlab:function [] = Buckling_False_Position()%Buckling_False_Position finds the value of max applicable load, F, that %the beam may support before collapse. %Calculate tube weight:dens=2.581; %slug/ft^3 http://www.clearpvcpipe.com/pdf/ClearPVCspecs.pdf OD=8.625/12; %OD of pipe in ft (SEE BOM)ID=7.943/12; %ID of pipe in ft (SEE BOM)L=15; %Length of pipe in ftV=(pi()/4)*(OD^2-ID^2)*L; %Volume of pipe in ft^3W=dens*V*32.2; %weight of the pipe in lbfWap=W/4; %weight at each connection point, assuming it's distributed %evenly across two bars with 2 connection points on eact bar %Calculate Pcra=1.5/12; %assuming a square x-section, the width in ftt=.12/12; %thickness of wall in ftb=a-2*t; %inner distace between wallsA=(a*a)-(b*b);l=10; %length in buckling in ftSyc=63100*(12^2); %Yield strength of A513 in lb/ft^3 (MATWEB)E=29700000*(12^2); %Elastic modulus of A513 in lb/ft^3 (MATWEB)e=OD/2+a/2+1/12; %eccentric distance, 1/2 of steel thickness + 1/2 OD of %vacuum tube + distance between edge of steel and vacuum tube c=a/2; %1/2 the distance across the cross-section of the hollow square barI=(1/12)*a*a^3-(1/12)*b*b^3; %Inertia of the bark=sqrt(I/A); %radius of gyrationf=@(F) F/A-Syc/(1+(e*c/k^2)*sec((l/(2*k))*sqrt(F/(A*E))));Fl=1;Fu=10000;Fn=Fu-f(Fu)*(Fu-Fl)/(f(Fu)-f(Fl));ed=.05;ea=100;iter=0;imax=100;while ea>ed && iter<imaxif f(Fl)*f(Fn)<0;Ft=Fn;Fu=Fn;elseif (f(Fl)*f(Fn))>0;Ft=Fn;Fl=Fn;enditer=iter+1;Fn=Fu-f(Fu)*(Fu-Fl)/(f(Fu)-f(Fl));ea=(abs((Fn-Ft)/(Fn)))*100;endFr=Fn;FOS=Fr/Wap;%ezplot(f,[1200,2000]); grid minor;fprintf('\n F (lbf) is: %.0f \n FOS is: %.0f \n The percent error is: %.3f \n',Fr,FOS,ea);end

Solution:

>> Buckling_False_Position

F (lbf) is: 1617

FOS is: 84 

The percent error is: 0.006

Parameters:

• 10ft long steel tube

• 1-1/2” square

• 0.120” wall

• A513 steel

Graphical Method using Matlab:>> ezplot(f,[1200,2000]); grid minor;

1200 1300 1400 1500 1600 1700 1800 1900 2000

-1.5

-1

-0.5

0

0.5

1

1.5

x 105

F

F/A-Syc/(1+(e c/k2) sec((l/(2 k)) sqrt(F/(A E))))

Support Buckling Results

• We achieve a FOS well over what we would ever need for the selected support frame in buckling under worst case scenario

• Our frame can support the weight of the tube, and is feasible

• We can, if desired, reduce frame cross-section size and thickness if further analyses show large FOS as well

Engineering Analysis – StructureLeg Center Deflection

Worst case scenario:15’ Long PVC Schedule 408” Diameter10’ long square A513 tube1-1/2”

0.120” wall

A513 steel

Assumptions:Weight of vacuum is halved

between the two legs, as is the upper frame structure

1 foot long leg

Schematic

Reactions and DeflectionIn the diagram below, dimension a is the

distance to the front support block and b is to the center of the wheel axel.

F includes half the weight of the tube and the upper support structureResult: ymax=-3.30E-04

inches

Engineering Analysis SummaryProposed Requirement Metrics

Tower height: up to 5 meters (~16ft)Tower size: 6” DiameterNumber of Towers: 1Pump Speed: 6.25 cfm Pump Type: 2 stage Rotary (mechanical roughing

pump)Evacuation Time: 5.25 mins Ultimate Pressure: 15 microns (0.015Torr or 2Pa)Negative (Critical) Pressure – Factor of Safety: 3.94No Isolation Valves Manual Object LiftingElectromagnetic Release MechanismMobile Support Structure

Risk AssessmentID Risk Item Effect Cause

Likelihood

Severity

Importance

Action to Minimize Risk

1

Pipe Implodes

under Pressure

• Safety Hazard

• Project ruined

• Pipe wall thickness

• Material1 3 3

a) Determine critical pressure of pipe, with safety factor

2 Damages to pipe

• Loss of visibility

• Loss of Vacuum

• Shipping• Human

Error2 2 4

a) Careful shipment and assembly

b) Pick location where pipe is safe from accidental damages

c) Determine pipe resistances to scratches, crack, etc.

3 Pump Over heat

• Loss of efficiency

• Fire hazard• Pump

replacement

• Improper pump size

• Poorly ventilated

• Left on

1 2 2

a) Adequate space around pump for ventilation

b) Turn pump off when not in use

c) Limit the number of consecutive runs if needed

d) Analyze pump specifications

4 Tower Falls Over

• Safety Hazard

• Damages to Surroundings

• Project Ruined

• Poorly supported

• Earthquake• Weak

structure

1 3 3

a) Ensure tower can withstand its own weight

b) Develop sturdy designc) Attach tower to surrounding

wall, railings, etc. at different heights

ID

Risk Item Effect Cause L S I Action to Minimize

Risk

5Any

sealing leak

• Loss of Vacuum• Noisy• Increased

depressurize time

• Bad Sealant• Gaps in o-

rings• Surface

impurities 

3 2 6

a) Require minimal seal pointsb) Research proper sealing

techniques for each component

c) Monitor pressure change

6Object Impact

breaks Base

• Object destroyed• Safety hazard• Pipe base broken• Loss of vacuum

• Cannot support objects force

1 2 2

a) Determine maximum force on impact (including safety factor)

b) Properly correct for that force with cushion, net, etc.

7

Laser Sensor Looses item

• Loss of data(position and time)

• Improper sensor alignment

• Sensor range inadequate

• Power loss

2 2 4

a) Determine whether vertical position sensor can detect all objects

b) Properly align sensor(s) with object

c) Ensure pipe connection can withstand that force

8Inaccurate

Gauge Reading

• Improper data display

• Improper vacuum

• Cheap gages• Not calibrated

correctly1 1 1

a) Calibrate all gage regularly (note in manual)

b) Purchase accurate & Reliable gages (tolerance)

9 Stolen components • Device unusable

• Components left out/unlocked

1 2 2

a) Bring components out when needed

b) Lock components up when not in use (near or away from tower)

ID Risk Item Effect Cause L S I Action to Minimize

Risk

10 Loss of Data

• Cant calculate gravity, drag and other data

• Loss of power• Software

malfunction1 2 2

a) Ensure Proper Electrical Connections

b) Capture all required datac) Possible sore multiple

run data

11Unsuccessful Release of objects

• Items does not fall

• Horizontal motion occurs

• Unsynchronized release

• Mechanism doesn’t open

• Release timing off

• Loss of power

2 2 4

a) Release objects simultaneously

b) Platform adequately centers objects

c) Robust latching mechanism

12Lifting device

Malfunction

• Item does not lift

• No dropping experiment

• Broken wire/ claw

• Loss of power• Improper motor

power

2 2 4

a) No lifting device, load form top

b) Ability to easily hold weight & size of objects

c) Ensure wire/cable does not get stuck

13Improper

use of system

• Compromises system integrity

• Poorly written manual

• Complicated operation

• Unauthorized use

1 1 1

a) Create intuitive design b) Create detailed

operators manualc) Limit use to qualified

individuals

Test Plan# Test Description Comments/Status

1 Energy Dissipation Control Drop heaviest object

2 Test Release Mechanism Drop Object from any height

3 Position sensor accuracy for objects Sensors can be mounted / tested without tube

4 Ultimate pressure Considering pump size / leaks/ chamber volume

5 Pressure gage accuracy Connect vacuum to pressure gage only

6 Temperature gage accuracy Calibrate Sensor

7 DAQ device inputs Position and time (from sensor(s))

8 Computer Software Outputs Computer outputs from on DAQ & human inputs

9 Tower stability Simulate maximum applied forces

10 Extra vacuum tests How things react inside our vacuum

MSD I Project ScheduleAug September October November December1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Planning & Execution

Problem Definition

System Design

Subsystem Design

Detailed Design

Address Open Issues

Complete Release Mechanism Design

Schedule PDR and Invite Participants

Update Test Plan

Update Edge

Finalize Support Structure

Complete Drawing Package

Finalize Bill of Material

Finalize Continuous Lift Concepts

Bill of Materials

Questions?