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P14471 Vibration Testing Apparatus II Final Review

5/13/2014

Brett Billings

Jacob Gardner

Nick Greco

Ron “Sparky” Jimbo

Claire Kobal

Ryan Selig

Ashley Waldron

Agenda

2

Revisit of Requirements

Build

Test

Issues

Lessons Learned

Project Management

Appendix

3

Revisit of Requirements

Customer Requirements

4

Engineering Requirements

5

Number Requirement Raw

Score Units

Ideal

Measure 1 Displacement of luminaire 69 in 1/32

2 Vibration of luminaire 69 cycles/min 2000

3 Duration of vibration test 69 hours 35

4 Isolate motor from oil spills 45 Binary Yes

5 Maintenance Documentation 44 Survey (easy to follow) 80%

6 Mount pendant configuration 35 Binary Yes

7 Operation Documentation 33 Survey (easy to follow) 80%

8 Machine won't operate if crankshaft enclosure is open 25 Binary Yes

9 Completely stop machine with Emergency Stop 25 seconds < 10

10 Maximum voltage of Motor 25 V AC 240

11 Minimize number of operators 21 people 2

12 Max weight of mounted luminaire 20 lbs > 150

13 Visually display settings and status of test 18 Binary Yes

14 Steps to set up 16 steps < 10

15 Setup Time 16 seconds < 120

16 Low Sound 15 dBA < 85

17 Minimize pinch points 15 Count < 3

18 Total materials cost 15 $ < 4,000

19 Mount stanchion configuration 7 Binary Yes

20 Mount yoke configuration 7 Binary Yes

21 Mount trunnion configuration 7 Binary Yes

22 Machine footprint 5 in2 < 34X48

House of Quality

6

UL844

7

2000 RPM

1/32’’ displacement

35 hours

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Build

Frame Assembly

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Steel was assembled and welded in shop

All welded joints were annealed to relieve hardness caused by the heat during welding

C-channel was machined to fit on top of frame and to hold flange assembly

Baseplate for crankshaft mechanism was modified and mounted to frame

Crankshaft Modifications

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Modifications to improve adjustment:

Added access holes to connecting rod

Replaced 3/8-24 set screw with a 3/16-100 set

Re-machined T-block for bushing

Replaced springs with weaker ones

Access hole added to rear guard

Additional Work

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Dial Gauge

Added magnetic back plate

Created alignment block to ensure

gauge is perpendicular to box (cosine

error)

Top guard was re-machined in order to

ensure adequate overhang for bolts

Painted steel frame to resist rusting

Belt Guard Mount There was a misunderstanding in the

machine shop and half of our original belt

guard was thrown away

A new, rectangular guard was fabricated

Elongated holes were drilled in the L-

brackets to allow for vertical adjustment

Issue: Seems like there might be a lot of

vibration. Never tested with machine on.

12

Encoder Mount

Original design:

Attach mount to bottom of belt guard

Issue:

Belt guard adjustment requires encoder to be adjusted as well

Final design:

Metal arm extending horizontally from L-bracket with rubber

pad to prevent excess movement

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Control of Motor

Variable Frequency Drive added to control motor frequency

VFD spec’d based on:

Remote start/stop

Remote ramp up or ramp down the speed of the motor

External faults that could be used as an E-Stop

14

Feedback from Apparatus

Closed loop control system

RPM read by rotary encoder and sent to

MCU

Raw feedback from the encoder is processed

and displayed on LCD

Encoder needs to have high enough

resolution to keep the error within 1% of

2000 RPM

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Microcontroller: Programming

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Microcontroller Unit (MCU) is a product of Texas

Instruments (TI) under the MSP430 family

MSP430G2452 – Main program and LCD communication

MSP430G2553 – VFD switching logic

TI Launchpad board used to reprogram MCU

Microcontroller: Interfacing

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Supply voltage is 3.3 V DC from voltage regulator unit

MSP430G2452 – Drives control and logic for the test LCD (10 pin connections) Feedback from Encoder Output A (1024 PPR)

Control switch to manually pause/resume test (10 kΩ pull-up) Primitive serial data to MSP430G2553 (2 pin connections)

MSP430G2553 – Directly controls VFD through switches Toggles transistors (switches) used to send digital data to VFD

Additional control switch to power on and off both MCUs and LCD

Display Unit

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20x4 HD44780 (Hitachi) Liquid Crystal Display (LCD) with

LED backlighting

Implements ASCII printable characters

Character display: 4 rows, 20 columns

Commands entered as parallel data

Data [7..0]; Register Select; Enable

Write mode; fixed contrast and lighting

Microcontroller: Logic/Implementation

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Initialization

Wait for about a second for display to power on before writing

Set internal clock frequency to 16 MHz Varying clock speed essentially varies all delays and timing involved

Configure input and output pins

Write static items to display

Initialize integer variables

Configure and enable Timer and Edge Triggered interrupts

Interrupt handlers Timer A: Increments a time-keeping variable

Edge 1: Increments frequency counter from Encoder output

Edge 2: Toggles a pause variable from pause/resume control switch

Microcontroller: Logic/Implementation

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Display routines Send Command Simple routine to send commands in form of parallel data

Command specified as binary string

e.g.: SendCommand("1101010010"); sets character position to the start of line four

Enable automatically set low and then high to send the full command

Write Character Converts inputted character to binary equivalent and sends the command

Direct ASCII compatibility due to HD44780 controller

Write String Writes a sequence of characters; e.g.: WriteString(“Hello world!”);

Microcontroller: Logic/Implementation

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Main algorithm (simplified)

Test paused (or stopped)

Signal VFD to stop motor

Hold state, including timer and latest status message on display

Test resumed (or started)

Signal VFD to start motor and set to default speed (~2000 RPM)

Resume state

For each passing second…

Update time both internally and on display

Count up to a specific frequency from encoder signal

Use specific frequency and time passed to accurately calculate RPM

RPM within 1% of target: normal operation; else within 5%: ramp motor speed up or down through VFD; else outside 5%: pause test

Pause test if no encoder signal detected or 35 hours elapsed

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Test

Current Testing Status

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# Engineering Requirement

Raw

Score Importance

Ideal

Measure Units Tolerance Test Plan Status

1 Displacement of luminaire 69 5 1/32 in ± 3% 1A, 1B, 4 NOT TESTED

2 Vibration of luminaire 69 5 2000 cycles/min ± 2% 2A, 2B NOT TESTED

3 Duration of vibration test 69 5 35 hours 2A, 2B, 3 PARTIAL

4 Isolate motor from oil spills 45 4 Yes Binary 2A, 2B PASS

5 Maintenance Documentation 44 2 0.8 Survey 8 NOT TESTED

6 Mount pendant configuration 35 5 Yes Binary 5 PASS

7 Operation Documentation 33 2 0.8 Survey 8 NOT TESTED

8 Machine won't operate if crankshaft enclosure is open 25 4 Yes Binary 7A, 7B PARTIAL

9 Completely stop machine with Emergency Stop 25 4 < 10 seconds 7A, 7B PARTIAL

10 Voltage of motor 25 5 240 V AC N/A PASS

11 Minimize number of operators 21 3 <= 2 people 6A, 6B PARTIAL

12 Max weight of mounted luminaire 20 5 > 150 lbs 2A, 2B NOT TESTED

13 Visually display settings and status of test 18 4 Yes Binary 3 PASS

14 Steps to set up 16 3 < 10 steps 6A, 6B PARTIAL

15 Setup Time 16 4 < 120 seconds 5A,5B,6A, 6B PARTIAL

16 Low Sound 15 3 < 85 dBA 7A, 7B PARTIAL

17 Minimize pinch points 15 3 < 3 count 7A, 7B PARTIAL

18 Total materials cost 15 3 < 4,000 $ N/A PASS

19 Mount stanchion configuration 7 5 Yes Binary 5 NOT TESTED

20 Mount yoke configuration 7 5 Yes Binary 5 NOT TESTED

21 Mount trunnion configuration 7 5 Yes Binary 5 NOT TESTED

22 Machine footprint 5 3 < 34X48 in2 5 PASS

Encoder Testing

Initial testing done independent of apparatus with a DC motor

to evaluate following components:

Output signal’s amplitude

Output frequency

Power and control connections

Allowed encoder to be integrated with apparatus and

connected to MCU to display speed on LCD

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VFD Control Testing

The VFD control signals were also tested independently on a

proto-board for isolation purposes

The VFD was programed for the motor used as well as for

the digital outputs needed for the control signal

To remotely control the VFD power transistors were used as

switches

The control of these switches would be coming from the

MCU

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Safety Test

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Failed at RIT – 6 of 14 items are “No” Labeling, lockouts, 2nd E-stop

Will pass at CCH in Syracuse Ordered additional lockout & lock

Setup Test

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Did not meet original engineering metrics

Target: 2 minutes, 10 steps

Actual: 16 minutes, 14 steps

Should have used previous team as benchmark

Drastic improvement vs 49 minutes & 31 steps

Can be done with one person though

Setup Test

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Standard Work for CCH – steps, time, visual aids

Method to reach displacement in 2 adjustments

Use of dial gauge

Quick reference table

1 turn = .019’’

Reliable to +/- 3%

Current Adjust to Current Adjust to Current Adjust to

> .03130 Backoff 0.0210 0.02613 0.0100 0.02063

0.0310 0.03113 0.0200 0.02563 0.0090 0.02013

0.0300 0.03063 0.0190 0.02513 0.0080 0.01963

0.0290 0.03013 0.0180 0.02463 0.0070 0.01913

0.0280 0.02963 0.0170 0.02413 0.0060 0.01863

0.0270 0.02913 0.0160 0.02363 0.0050 0.01813

0.0260 0.02863 0.0150 0.02313 0.0040 0.01763

0.0250 0.02813 0.0140 0.02263 0.0030 0.01713

0.0240 0.02763 0.0130 0.02213 0.0020 0.01663

0.0230 0.02713 0.0120 0.02163 0.0010 0.01613

0.0220 0.02663 0.0110 0.02113 0.0000 0.01563

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Issues

Luminaire Vibration

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Luminaire vibrates more than machine

Extra conduit was threaded

Set screw was tightened

CCH not able to help by email/phone

Resolution:

Try plumber’s tape

Consult CCH in Syracuse during final testing

Motor Mount

Excess vibration in motor mount at 1/3 speed

Mount was reinforced with t-shaped brace

Top View

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Electrical

VFD damaged during initial testing

Root cause analysis performed

VFD replaced by CCH

All future wiring done by licensed electrician

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Electrical

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Encoder mounting

Coupler needed to be modified

Coupler broke right before shipping

Enclosures

Shipped apparatus without

LCD stuff

Control changes from CCH at demo

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Lessons Learned

Experience Gained

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Combined structural mechanics with vibration

Required learning more in-depth features of structural

mechanics & natural frequency

Required learning of ANSYS Workbench to analyze the stress

at the operating frequency and the natural frequency of the

frame

Electrical component selection & wiring

Lessons Learned

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Review the previous MSD team’s work more

thoroughly before starting

Verify existing parts match CAD models

Communicate effectively between both team

members and others helping with the project

Weigh the risks of using free help vs. hired

professionals

Lessons Learned

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Iterative design process

Escalate issues when you can’t solve them

yourself

Compromise on differences of opinions

between team members

Work together to meet internal deadlines

Clearly define team member roles

e.g. Document owners

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Project Management

Budget

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Original Budget = $4,000.00

Current Costs = $2,978.88 Parts = $2,540.33 S/H = $198.55 Expected Travel = $240.00

Items saved on: CCH donated VFD & replacement ($290x2) CCH paid for shipping ($600) No welding fees ($400) No electrician fees ($200)

https://edge.rit.edu/edge/P14471/public/WorkingDocuments/Detailed%20Design/BOM_rev6_tracking.pdf

Risk Analysis

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Risk Effect Cause Severity Likelihood Score Action Item Owner Due

Poor design 3 2 6 Make it adjustable Brett DONE

Disp. changes during test 3 2 6 Calculate torque required on bolts so displacement won't slip. Brett DONE

Poor calibration 2 1 2 Define calibration procedure and schedule Jake 4/15/2014

Crankshaft slipping 3 2 6 Evaluate previous team's design Nick DONE

RPM changes during test 3 2 6 Design closed loop feedback and VFD to adjust RPM Ryan DONE

Belt slips 2 2 4 Use v-belt and belt guard (for oil drip) Ashley DONE

Motor inefficiencies 3 1 3 Accept Risk --- DONE

Belt is too loose 1 2 2 Design motor mount to be adjustable Ashley DONE

Frame misalignment 2 1 2 Write procedure to verify conduit is 100% vertical Claire 4/15/2014

Motor burns out Costly to replace, test fails Motor burns out 3 1 3 Calculate required torque and RPM, select appropriate motor Ron DONE

Crankshaft improperly lubricated 3 1 3 Define maintenance procedure and schedule Ron 4/15/2014

Motor is too loud 2 1 2 Add motor enclosure, sound damping, hearing protection Brett DONE

Vibration of frame 2 1 2 Add sound damping, add hearing protection Brett DONE

Luminaire breaks and rattles 2 1 2 Accept Risk - test will be ended early --- DONE

Operators don't wear earplugs 1 2 2 Accept Risk - exposure duration is still low --- DONE

Fixed guard not in place 3 1 3 Place warning labels on apparatus Brett 4/15/2014

Machine not properly guarded 3 1 3 Install polycarbonate guard and belt guard Brett DONE

Energy source not isolated 3 2 3 Install location to lockout machine Brett DONE

Lockout not observed 3 1 3 Accept Risk --- DONE

Button is broken 3 1 3 Define maintenance schedule Ryan 4/15/2014

Electrical failure 3 1 3 Have CCH check work with certified electrician Ron DONE

Pinch points exist Operator injury could occur Existence of pinch point 2 3 6 Guard all pinch points Brett DONE

Setup requires awkward positioning 2 2 4 Design conduit to be assembled first, then attached all at once Claire DONE

Luminaire is too heavy 2 1 2 Specify use of lift assist or 2nd operator, Design for use Brett DONE

Project scope 2 2 4 Use current fixtures Claire DONE

Fixture doesn't work with frame 1 1 1 Change frame and/or fixture design Claire DONE

Oil spill on motor connection Motor failure/smoke Leakage 1 2 2 Offset motor so oil can't drip on it Ashley DONE

Vibration is same as natural frequency 3 2 6 Perform ANSYS Analysis, add supports to change natural frequency Nick DONE

Improper construction 3 2 6 Use certified welder Nick DONE

Poor material selection 3 2 6 Perform ANSYS Stress Analysis Nick DONE

Luminaire is too heavy 3 2 6 Perform ANSYS Stress Analysis Nick DONE

Project runs over budget

Customer is dissatisfied,

engineering requirements must be

sacrificed

Unforeseeable expenses 2 2 4 Proper budgeting/compare prices/buy standard sizes Nick DONE

Design decision 1 2 2 Accept Risk --- DONE

Changes in technology compared to original 1 2 2 Accept Risk --- DONE

Correction of mistakes 3 2 6 Participate in milestone design reviews ALL DONE

Delay in Tool Shop 2 2 4 Schedule machine time 1 week prior - not required, drop in OK Ashley DONE

Materials are delivered late 2 2 4 Order during Winter Break Nick DONE

Poor planning 2 1 2 Maintain accurate project plan and adjust as needed Brett DONE

Member doesn't finish assigned work 2 1 2 Refer to Norms and Values - seek help or adjust workload ALL DONE

Electrical shock from apparatus Operator injury could occur Improper wiring 3 2 6 Have CCH check work with certified electrician Ron DONE

RPM can't be measured accurately Apparatus doesn't meet UL844 Encoder vibrates too much 3 1 3 Add damping Jake DONE

Unable to integrate measurement devices with

display

Machine is just as difficult to setup

and monitor as beforeLack of knowledge 2 2 4 Research integration requirements and prepare LabView backup Ryan DONE

Can't get items (Motor, VFD, etc.) from Eaton in

available time

Need to purchase items instead,

increased cost of projectLead time is too long 2 2 4

Request items by specified date from CCH and ask for delivery date. Have

backup supplier prepared.Ron DONE

Apparatus fails test plan after shipping to CCHHard to fix apparatus once it's in

Syracuse

Can't fully test apparatus at RIT due to safety

and power supply requirements3 2 6

Check on shipping LT to Syracuse, investigate using U-haul to deliver it

ourselves, ask if CCH has facilities on site we can use for modificationsBrett DONE

Severity Scale: 1 = Minor, 2 = Noticeable, 3 = Severe

Likelihood Scale: 1 = Improbable, 2 = Possible, 3 = Very Likely

Customer is dissatisfied, Students

receive poor course grade, RIT's

reputation is negatively impacted

Operator injury could occurApparatus is not ergonomically safe to setup

Frame falls apart Test fails, costly to fix

Can't mount all configurations typesCustomer is not able to test some

configurations

Apparatus is larger than existing oneCustomer is dissatisfied, new holes

must be drilled in floor

Project deadline is not met

Operator injury could occurMachine starts during maintenance

Operator injury could occurEmergency stop doesn't work

Machine is too loud

Operator injury could occurMachine operates when moving parts exposed

Hearing conservation or

engineering intervention is

required

Apparatus doesn't meet UL844Vibration is not 2000 cycles per min

Apparatus doesn't meet UL844Displacement is not equal to 1/32in

What’s Left?

Remaining work:

Finalize technical paper

Travel to Syracuse for final testing – Test Plan B’s

Fix issues detected during testing

Solve excessive luminaire vibration

Deliver maintenance & operation documentation

If we don’t finish by 5/22:

Enough work for a Phase III?

Work for a Co-op?

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Questions?

42

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Appendix

Room Layout

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Selected Design

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Interchangeable Conduits

Motor with V-belt

VFD

Digital Dial Gauge

Encoder

LCD, Microcontroller

Polycarbonate Guards

E-stop

Paint for Rust Protection

Test Plans

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Refer to Excel document

https://edge.rit.edu/edge/P14471/public/WorkingDocuments/MSDII_B

uild%20Test%20Documentation/P14471 Test Plans_Rev2.xlsx

or EDGE

https://edge.rit.edu/edge/P14471/public/Build%2C%20Test%2C%20Do

cument

Full Risk Analysis

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See EDGE

https://edge.rit.edu/edge/P14471/public/ProjectManageme

nt/Risk%20Analysis.pdf

VFD Damage Incident

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See EDGE

https://edge.rit.edu/edge/P14471/public/WorkingDocumen

ts/VFD%20Damage%20Incident/VFD%20Damage%20Incide

nt.pdf