RIT MSD Team P08454 Verification Test Packetedge.rit.edu/edge/P08454/public/Testing/Verification...

RIT MSD Project RIT MSD Team P08454 Verification Test Packet

RIT MSD Team P08454 Verification Test Packet

Author:Brian Bullen

Consultants:Anthony Squaire

Alan MatticeCody Ture

Charles TrumbleAron KhanJeff Cowan

Andre McRucker

Document Version: 4.0 1 7 February 2008Location: https://edge.rit.edu/content/P08454/public/Testing/Verification_Test_Packet

https://edge.rit.edu/content/P08454/public/Testing/Verification_Test_Packet


ABSTRACT

This packet contains test procedures to test all specifications set forth in the document created from the customer needs that can be quantified. The specifications shall be met using the predetermined procedures. If possible within the time constraints of the project, the tests should be run over a set of three prototypes to allow for more statistically sound results.




TABLE OF CONTENTS

1 INTRODUCTION…………………………………………………………………...4

1.1 Purpose/Objective……………………………………………………………41.2 Definitions…………………………………………………………………....41.3 References……………………………………………………………………4

2 APPROACH………………………………………………………………………….6

2.1 Material Resources…………………………………………………………...62.2 Skills Required……………………………………………………………….6

3 PROCEDURES………………………………………………………………………7

3.1 Thrust/ Reverse Thrust…………………………..…………………………...73.2 Power Consumption………………………………………………………….83.3 Shaft Balance..…………………………………………………………….…93.4 Pressure Rating……………………………………………………………..103.5 Weight (Air vs. Water)……………………………………………………..113.6 Volume……………………………………………………………………...123.7 Environmental Temperature Variance………….…………………………..133.8 Lifetime……………………………………………………………………..14

APPENDICES

A Results Spreadsheet for each Procedure

B Test Rig Set-up




1 INTRODUCTION

1.1 Purpose/Objective

This packet contains test procedures to test all specifications set forth in the document created from the customer needs that can be quantified.

The tests herein include measurements of: Thrust (lbF) Power Consumption (W) Vibration Amplitude (in) Pressure (psi) Weight (oz) Volume (in3) Temperature (oF) Time (hours)

1.2 Definitions

1.3 References

Specifications defined:Specification

Number Design Specification Unit of Measure

Marginal Value Ideal Value

Physical Requirements 1 Continual Thrust lbf 4.8 122 Motor Power Draw Watts 80 50.4

3Mountable to the prototype ROV originally designed in SD team project P06606 Yes/No Yes Yes

4 Uses standard (off the shelf) fittings / connections Yes/No Yes Yes5 Seals must withstand at least 173 psi Yes/No Yes Yes

6 Available Reverse ThrustRatio Reverse

to Forward 1/2 ¾

7 Output shaft must be balanced

Maximum Tolerance (Inches)

0.001 0.0001

8 Depth (Pressure) Feet (psi) 400 (173) 800 (346)9 Weight (in the air) Ounces (oz) 40 28

10 Weight (in the water) Ounces (oz) 28 1811 Size Comparable to Market Competition Volume (in^3) 18.8851 15.881212 Operate at Varied Temperatures Fahrenheit 38-75 34-100 Production and Document Constraints

13 Open Architecture Design Yes/No Yes Yes

14Open Source Documents and Drawings so that future SD teams can utilize this design in future projects Yes/No Yes Yes

Quality Control




15 Robust Design Hours 168 252 Compatibility

16Modular so that the housing design integrates with the SD team project P08456 Yes/No Yes Yes

Text References:

- Inman, Daniel J. Engineering Vibration Third Edition . 2008 . Pearson Education, Inc.

- Shigley, Joseph E. Mischke, Charles R. Budynas, Richard G. Mechanical Engineering Design Seventh Edition . 2004 . McGraw-Hill

2 APPROACH




2.1 Material Resources

Defined per test

2.2 Skills Required

To execute the tests defined within this packet, a basic knowledge laboratory procedure is a must. That is, knowing how to control and run an experiment so that all variables beyond the critical unknowns are maintained without deviation so that only the most important pieces are tested. Knowledge of Microsoft Office is also applicable for data collection and reporting.

3 PROCEDURES




3.1 Thrust/ Reverse Thrust

3.1.1 Materials

Test rig (defined in appendix B) Three assembled prototype models of the ROV thrusters Laptop computer or other form of topside communication

3.1.2 Set-up

Place test rig in area with a low traffic flow and that is accessible to a power source (outlet)

Have software defined on a laptop or other source to control the thruster (topside control)

3.1.3 Test Steps

Connect all wiring to the thruster and make all power and communication connections needed for topside control

Attach the fully operational and sealed thruster to the test rig with the nozzle end upwards

Using the topside control, ramp up the voltage to the thruster making sure to note the thrust at each interval (1 interval = 1 V) for the range of 1V to 24V

Once all data points have been collected, stop all power to the thruster using topside control

Un-mount the thruster and remount it with the nozzle end downwards Flip the signal from the topside to make the motor spin in the opposite direction Repeat the process of ramping the power and recording thrust but make sure to

use the After all data is collected, remove the thruster from the test rig, remove electrical

cords and dry off for proper storage Repeat entire test for two additional prototypes to confirm functionality across the

design The data collected through this test shall be compared to data previously collected

from the Seabotix and Tecnadyne thrusters. Also, the data should meet or exceed the parameters set forth in the specifications defined in the references section of this packet (sect. 1.3). If the data is cause for a failure, then a retest can be done to confirm the results and possible contingencies should be put into effect if the specifications will not be met.

3.2 Power Consumption




3.2.1 Materials

Three assembled prototype models of the ROV thrusters Power source (outlet) Laptop computer to control the thruster (topside control) Multimeter to measure voltage and current usage of the thruster

3.2.2 Set-up

Place test rig in area that has a low traffic flow and that is accessible to a power source (outlet)

Have software defined on a Laptop or other source to control the thruster (topside control)

3.2.3 Test Steps



Using the topside control, ramp up the power slowly to 80% of maximum Measure the voltage and current draws at this level Using a form of Ohm’s law, the power being consumed can be calculated:

where V = voltage and i = current Ramp the power up to full and again measure the voltage and current draws and

recalculate the power consumption. Repeat the test on the two remaining thrusters Record all results The data collected through this test shall be compared to data previously collected


3.3 Shaft Balance




This section is not an explicit test as the test set-up for something like this would be far too involved for this short design project. The following sections outline the theory and calculation of a theoretical shaft unbalance. These equations can be used for larger or smaller systems by simply changing the material and dimensional constants.

3.3.1 Theory

Looking at the possible unbalance of the impeller shaft will lead to a harmonic force calculation that can be used to then calculate the fatigue that the supporting plain bearing will face. The system can be modeled as a 2-D rotating shaft with a general depth.

Constants: E = Young’s Modulus m = total mass mo = mass of unbalance e = radius of unbalanced mass = Damping Ratio (0.707 ~ under damped yet in control) n = Natural Frequency r = Speed of shaft r = Frequency Ratio

Governing Equations:

(1) (2)

Rearrange (1) and solve for e knowing that , at resonance, with 1% of the mass unbalanced:


Figure 1: Circular shaft with unbalanced mass to cause a harmonic force



Since the overall deflection needs to be very small, then the corresponding rotating unbalance radius will also be small.

Using (2), the force created by the unbalance can now be determined using the value e that was determined:

Surface strength of bearing material is 11,600psi. Use fatigue theory and the F found to confirm that the bearing can handle the unbalance:

(3)

where w is the length of the rotating cylinders and:

Knowing E1=1,131ksi, E2=10,000ksi, 1=0.37, 2=0.35:

3.3.2 Results

It is shown that if the tolerances are kept to within a one thousandth of an inch for the shaft and bearing surfaces, then the chance that any unbalance between the two surfaces can cause premature fatigue is non-existent.

3.4 Pressure Rating

3.4.1 Materials




Three assembled prototype models of the ROV thrusters Pressure vessel with thick walls to contain at least 1000 psi of pressure Water source (to fill pressure vessel) Compressed air (to pressurize pressure vessel)

3.4.2 Set-up

Assemble housing with all appropriate o-rings in place Check pressure vessel to make sure of the structural integrity of the device

3.4.3 Test Steps

Place the sealed housing into the pressure vessel Close the lid and fill the vessel with water so that as little air as possible is left

inside of the vessel Attached the compressed air hook-up and using the pressure gauge to measure,

slowly begin pressurizing the vessel to the 200 psi Once the vessel is pressurized, seal off the inlet and remove the compressed air

attachment Allow the test to sit for 10 minutes (if nothing happens in 10 minutes, then there

will be no leaks no matter how long it is left under pressure) Once the 10 minutes is up, use the release valve to slowly relieve the pressure

o Even if the pressure appears to be relieved, allow a few more minutes to be completely sure

Open the pressure vessel and completely dry off the outer surface of the housing to remove any extraneous water

Once completely dry, open the housing and inspect the insideo There should be no water in the inside of the housing

If test is successful, re-test at the ideal value of ~346 psi The data should meet or exceed the parameters set forth in the specifications

defined in the references section of this packet (sect. 1.3). If the data is cause for a failure, then a retest can be done to confirm the results and possible contingencies should be put into effect if the specifications will not be met.

3.5 Weight (Air vs. Water)

3.5.1 Materials




Three assembled prototype models of the ROV thrusters Digital fish scale Tank big enough to fully submerge the thruster while it is hanging vertically

3.5.2 Set-up

Fill up the tank with enough water so that the thruster will be fully submerged while hanging vertically

3.5.3 Test Steps

Hang the thruster from the fish scale so that it is totally supported by the scale Read the weight as it hangs in air and record Leave the thruster hanging and move it to the tank and submerge the thruster

completely under the water Repeat for the additional thrusters Record all results The data collected through this test shall be compared to data previously known


3.6 Volume

3.6.1 Materials




Three assembled prototype models of the ROV thrusters Tank big enough to fully submerge the thruster Permanent marker A level, and sturdy surface

3.6.2 Set-up

Fill the tank to a minimum volume (two gallons is good) Mark this level Add one cup of water and again, mark this level Repeat the previous step until 25 cups have been added and marked Empty out the water so that that beginning level of the test will be the two gallon

mark, this is the zero plane

3.6.3 Test Steps

Gently place a thruster into the tank Allow the fluid to settle so that readings can be taken Measure approximately how many cups of water the thruster displaces Record this volume and repeat the entire test for the two remaining thrusters Record all results The data collected through this test shall be compared to data previously collected


3.7 Environmental Temperature Variance

3.7.1 Materials




Three assembled prototype models of the ROV thrusters Tank big enough and insulated adequately to keep thermally stable within +/-4oF Ice Hot water source Thermal measurement device Laptop computer to control the thruster (topside control)

3.7.2 Set-up

Fill the tank with warm water at approximately 75oF (Make sure the water volume is at least 10x the volume of the thruster to help in maintaining temperature)

Connect all wiring to the thruster control the thruster Connect thermal measurement device so that it monitors the tank water

temperature Make sure feedback from thruster is working so that the rpms of the shaft, power

consumption and internal temperature can be measured as the test proceedso Write a software program to collect the above data (basically the control

GUI)

3.7.3 Test Steps

Check again that the water is at the maximum temperature of 75oF Start running the thruster and leave it running at 80% max power for 30 minutes At one minute intervals, record measurements of rpms, power (voltage*current)

usage, and internal temperature As the test proceeds, continue monitoring the tank water temperature and adjust

by either adding ice or more hot water to keep the water temp at the test temperature

After 30 minutes, stop the thruster and remove Empty a good portion of the warm water and refill the tank with very cold water

from the tap Add ice to the water until the water temperature reaches the lower limit: 38oF Run the thruster at 80% max power for 30 minutes At one minute intervals, record measurements of rpms, power (voltage*current)

usage, and internal temperature As the test proceeds, continue monitoring the tank water temperature and adjust

by either adding ice or more hot water to keep the water temp at the test temperature

After 30 minutes, stop the thruster, remove, and dry off for storage Time Permitting: Repeat the entire test for the additional two thrusters to make the

test more statistically sound The data should meet or exceed the parameters set forth in the specifications

defined in the references section of this packet (sect. 1.3). If the data is cause for a failure, then a retest can be done to confirm the results and possible contingencies should be put into effect if the specifications will not be met.




3.8 Lifetime

3.8.1 Materials

Test rig (defined in appendix A) Three assembled prototype models of the ROV thruster Laptop computer or other form of topside communication A secure room or location so that no disturbances will occur with the test

3.8.2 Set-up

Place test rig in area that is secure and accessible to a power source (outlet) Have software defined on a Laptop or other source to control the thruster (topside

control)o The software for this test will create repeating duty cycles of 30 minutes

forward, and then 30 minutes in reverse to simulate the vertical azimuth thrusters work load

3.8.3 Test Steps



Place a cover over the top of the test rigs tank to minimize splashing and prevent human limbs from entering the tank

Start the duty cycle software The test can now be left to run for the prescribed time set forth in the

specifications (sect. 1.3) The test should be checked on at least once daily and more frequently if possible

to assure the test has not stopped or been tampered with During the test, software will be collecting data monitoring revolutions of the

shaft, power consumption, internal housing temperature, outside fluid temperature, and how many cycles the thruster has completed

If the test reaches the life set forth, then the test can be stopped and called complete

All data collected by the computer during the test should be tabulated and analyzed to identify any issues

The data collected should meet or exceed the parameters set forth in the specifications defined in the references section of this packet (sect. 1.3). If the data is cause for a failure, then a retest can be done to confirm the results and possible contingencies should be put into effect if the specifications will not be met.




APPENDICES

A Results Document

Results.xls

B Test Rig

(a) Materials

Large cylindrical tank Engine hoist Three lengths of square steel stock Three c-clamps Digital fish scale Power source


Figure: Test Rig Set-up



(b) Set-up

Place tank on a rolling platform for ease of storage and use Use two c-clamps to attach the medium length of the square steel stock

horizontally across the top of the tank Strap the thruster to the long piece of square tube steel stock Connect all communication and power wiring to the thruster Insert the long tube of square stock with the thruster attached to the small

length of square tube Use the third c-clamp to attach the short length of the square steel stock

vertically in the middle of the medium length steel stock Move the engine hoist over the test tank so that the hook is hanging

directly over the position of the long square tube Place the fish scale on the hook and attach the measurement end of the fish

scale to the long piece of square tube



RIT MSD Team P08454 Verification Test Packetedge.rit.edu/edge/P08454/public/Testing/Verification...

Documents

Transcript of RIT MSD Team P08454 Verification Test Packetedge.rit.edu/edge/P08454/public/Testing/Verification...