Mechanical Engineering senior project help!

profilehgjkd-
archive.zip

13 Report Guide 495.docx

SENIOR PROJECT TITLE

By

Student Name

NOTE: ERASE/REPLACE ALL ITALLICS AS YOU INPUT YOUR OWN WORDS!!!!

The purpose of making up this ‘guide’, and distributing it to students, is to help with the ‘framework’ of creating an engineering document. It contains the typical items that students should be aware of through their ‘Technical Writing’ course. And any technical writing text should be a reasonable reference. As we progress through the first quarter, students should be able to customize this ‘guide’ by replacing the existing words with their own. Examples will be shown, and many are visible via the internet.

This document has two purposes.

First, as a guide to writing a proposal, it will be evaluated at the end of the first quarter, and also at the end of January, when the proposal is ‘frozen’. Note that many parts of a ‘proposal’ will be the exact same content as in the final report. These items include the ‘Introduction’, ‘Methods’, and ‘Design’. However, the purpose of a proposal is to obtain approval from the instructor for this particular engineering project. Your proposal conclusion should reflect the criteria for a good MET Senior Project (e.g. addresses an engineering problem with engineering merit, is not too big, is not too expensive, can be done with your expertise and available resources).

As a guide to writing the final report, you should be able to use the outline to address those areas that were completed during the second and third quarters (e.g. construction, testing, discussion). This report is one of a few deliverables for MET495.

You should be able to present all of your information in this (soft) format. If you need to make an ‘image’ of a different CAD package, etc., then just go ahead and do it (make a jpg and paste it in). The same can be said of ‘Scheduling’, ‘Budget’, etc.

Note: I do not advise using pronouns. Please talk about the project, not yourself. If you decide to use a pronoun, I advise using ‘we’.

Good luck, Dr. J. Table of Contents:

1. Introduction Please use numbers and letters (on left), Page #s are req’d Page 4

a. Motivation

b. Function Statement

c. Requirements

d. Engineering Merit

e. Scope of Effort

f. Success Criteria

2. Design and Analyses

a. Approach: Proposed Solution

b. Design Description (picture, sketch, rendering)

c. Benchmark

d. Performance Predictions

e. Description of Analyses

f. Scope of Testing and Evaluation

g. Analyses (this is where you refer to each green sheet in Appx A)

i. Design Issue: 1, 2, 3, …

ii. Calculated Parameters

iii. Best Practices

h. Device: Parts, Shapes and Conformation

i. Device Assembly, Attachments

j. Tolerances, Kinematics, Ergonomics, etc.

k. Technical Risk Analysis, Failure Mode Analyses, Safety Factors, Operation Limits

3. Methods and Construction

a. Construction

i. Description

ii. Drawing Tree, Drawing ID’s

iii. Parts list and labels

iv. Manufacturing issues

v. Discussion of assembly, sub-assemblies, parts, drawings (examples)

4. Testing Method

i. Introduction

ii. Method/Approach

iii. Test Procedure

iv. Deliverables

5. Budget/Schedule/Project Management

a. Proposed Budget

i. Discuss part suppliers, substantive costs and sequence or buying issues

ii. Determine labor or outsourcing rates & estimate costs

iii. Labor

iv. Estimate total project cost

v. Funding source(s)

b. Proposed schedule

i. High level Gantt Chart

ii. Define specific tasks, identify them, and assign times

iii. Allocate task dates, sequence and estimate duration (use arrows, highlights)

iv. Specify deliverables, milestones

v. Estimate total project time (if it isn’t in the three digits of hours, refine your tasks and try again)

vi. Gantt Chart

c. Project Management

i. Human Resources: You are the most important human resource. Other HR may include mentors, staff, faculty, etc.

ii. Physical Resources: Machines, Processes, etc.

iii. Soft Resources: Software, Web support, etc.

iv. Financial Resources: Sponsors, Grants, Donations

6. Discussion

a. Design Evolution / Performance Creep

b. Project Risk analysis

c. Successful

d. Project Documentation

e. Next phase

7. Conclusion

a. Restate your design title and its complete design readiness.

b. Restate your important analyses and how this contributes to success.

c. Restate your design predicted performance vs actual performance, with respect to your requirements. Use bullets if appropriate.

8. Acknowledgements: For gifts, advisors and other contributors

9. References: You should reference your texts, web sites, technical papers and any other information supporting your proposal.

10. Appendix A – Analyses (each sheet has a number like A-2, with a description)

11. Appendix B – Drawings (each drawing has an ID and complies with ANSI Y14.5)

12. Appendix C – Parts List (use real brands and IDs)

13. Appendix D – Budget (use real numbers and report to the cent

14. Appendix E – Schedule (estimate all hours to the tenths, as our government does)

15. Appendix F - Expertise and Resources (special needs, people, processes, etc.)

16. Appendix G –Testing Data (a form to record your test data)

17. Appendix H – Evaluation Sheet (a form or spreadsheet to compute desired values)

18. Appendix I – Testing Report (create a report of what you expect to say, with blanks)

19. Appendix J – Resume/Vita

1: INTRODUCTION

1a: Motivation: You need to document an engineering problem

This project was motivated by a need for a device that would…

Write Function Statement.

Please use your Machine Design text for an example.

Write Requirements,

Thus, a device is required that would…weigh less than 10#...(numbers, please)…that would accept 10,000RPM…. that would accept a 1000# payload…..

Write Success Criteria:

This could be the ASME Design Competition ‘equation’, or refer to the requirements.

Write the scope of this effort:

For example, “will include only the carburetion portion of the engine.”

Write about a benchmark:

There is probably some similar problem and solution out there. Find one and compare your problem and solution to this benchmark.

Write about the Success of the project:

“Success depends on the final performance of the engine with the new carburetion being at least 10% more efficient than the traditional system.”

DESIGN & ANALYSIS

Write out how you conceived of the design.

A sketch may be appropriate in this section (from your journal, perhaps). Inserting a .jpg is appropriate.

This is also a good section to introduce your ‘engineering merit’ areas.

You should present a couple analyses in this section. Engineers typically use ‘green sheets’ to detail analyses (just like homework). Do it. Use standard formats (name, date, given, find, assume, etc.). Narrate your analysis in this section, but refer to Appendix A where you insert .jpgs of those same green sheets.

Two example analyses are appropriate. This conveys your engineering abilities sufficiently.

REQUIRED: You must clearly show (through your narration) the connection of meeting some R equirements, by applying an A nalysis, that results in a D esign parameter, and is rendered in a D rawing. This will be assessed regularly using a metric.

This is worth repeating in another format. Consider this background and explanation:

The engineering merit of this project can be exemplified through the use of a metric developed at CWU: RADD (Requirements, Analysis, Design Parameters, Documentation) and described below.

For example, salient Requirement(s) that support an application of engineering to this project are (weight, load, etc.)

Some types of engineering Analysis that will be used are the Flexure Formula, and FEA (etc.)

The Design Parameters that will be obtained from the analyses are the dimensions and shape of the main support beam…

Finally, these parameters will be Documented in the technical drawings as the device is rendered.

Only those students that complete this engineering work, will pass this course.

Predict performance of your device:

You must predict the performance of your device! Predict how fast it will go, or how much distilled water it will make in twenty minutes. Do it now, and then later you can test and compare its performance against your predictions.

METHODS & CONSTRUCTION

Write out how you intend to make your solution happen.

Example: This project was conceived, analyzed and designed at CWU (you can say this in your own words representing your own scenario). Working within the constraints of our university resources… parts will be made….

Describe construction of the device:

The device itself will be built in sections… Some parts of the device will be manufactured…. Construction will occur in a specific sequence. First, the… This project is made of 10 parts and 3 sub-assemblies. All but three parts will be obtained from suppliers. The three key components will be machined here at CWU. The first part…

Refer to renderings:

You should be able to refer to ANSI Y14.5 conforming drawing(s) in Appendix B. A drawing tree is required, and should reference all of your subsequent part and assembly drawings.

Write: Device Operation:

Projects vary in complexity, so this area may be longer for systems verses shorter for singular parts. In any case, the operation of your device should be clearly described.

Write: Benchmark Comparison:

This orifice is within 10% of the size of the commercially available version…(benchmarking!)…and will produce 10% more horsepower than the benchmark device.

Write Performance Predictions:

The efficiency of the device is predicted to be 80% and will be tested conforming to ASTM standard procedures….

TESTING METHOD

Write out how you will test your device. This is not a trivial scenario. You may have specific needs for resources, etc. For example, you may need a race-track to measure the improved stability of your car from those new struts (this was accomplished in a previous MET Senior Project). Or you may need any number of other resources or instruments.

Test Plan:

You should be able to predict what information you need to evaluate the success of your project. This information should directly reflect your requirements, such as a weight limit. Some of these data may be easy to obtain. In any case, you must make a ‘test plan’ that details how you will obtain all of the necessary information reflecting the performance of your device.

Test Documentation and Deliverables:

All data should be recorded. How it is recorded is up to you. It is strongly suggested that you make up a ‘form’ so that you have a preset document to use as you test your device. There may be ancillary data to collect, such as photos, that you may want to use for different purposes (e.g. your final report). Plan this ahead, so you have both the equipment and the human resources to get it done.

BUDGET/SCHEDULE/PROJECT MANAGEMENT

Write out how you will manage this project. An introduction should reference the ‘risk’ of completing the project. This is normally couched in terms of addressing ‘Risk Analysis’.

Most projects are susceptible to three primary risks: cost, schedule and project management.

Cost and Budget:

A parts list is shown in Appendix C. The parts list details their identification, description (specifications), sources and cost as shown in Appendix D. Relatively low-cost parts like nuts and bolts…

Some of the assemblies will require welding…

The cost of this project is supported by….

Labor costs are separated out and correlated to the time shown in the schedule. Rates are estimated at $100/hour and thus….

The total cost of this project is estimated to be $500.00 (or whatever number you think is appropriate). This includes…

Schedule:

The scheduling issue has to do with obtaining a ‘gizmo’ that can meet the performance specifications within a reasonable time-frame.

The schedule for this project is constrained by the MET 495 course and is shown in Appendix E. A schedule guide has been provided. This project will be completed by the last week of the third quarter.

Create Tasks:

All of the tasks have identifiers that allow the reader to see when they are active (start and finish dates) as well as duration (time to complete). It is required to have tasks that are of small enough scope to realistically associate the type of activity and its duration.

Create Milestones:

Milestones are required. Each milestone may define a ‘deliverable’ (e.g. report, constructed part) or an event (e.g. a review or other document).

Project Management:

Addressing ‘risk’ with regard to an ‘engineering project’ is typically described in the domain of ‘project management’. Our text in MET495A supports this discipline. The area includes issues of budget and scheduling, as well as other areas of risk (e.g. safety, resources). You must address some of these other areas, such as resources. But as your project vary, so will your need or the appropriateness to address areas such as safety. Please ask for guidance as you consider this task.

This project will succeed due to the availability of appropriate technical expertise and resources. Test equipment is available to use for…

The principal engineer will provide…(expertise in…)… and their resume is shown in Appendix J…

The project sponsor is committed to providing monetary support for…. It will also provide equipment for….

DISCUSSION

Write out how your project progressed.

This sounds easy enough. However, you should have recorded enough information in your journal so that you can narrate the evolution of your project from start to finish. Did you change your design at any time? Please detail these issues here in the discussion.

Discuss the things that were successful, but more importantly, discuss what was not successful. When you are discussing what was unsuccessful, talk about why you think it was unsuccessful and what you would do/did differently to make it successful.

Note: There should be many paragraphs/pages devoted to this section. This is where you talk about what actually happened during the year!.

CONCLUSION

Note: In the proposal report, you will include a statement of how your device meets with respect to requirements for a successful Senior Project. These ‘requirements’ include having ‘engineering merit’ and having the necessary ‘resources’ to get it done. In general, you want to ‘sell’ your project. So say something positive like:

“A device/model has been conceived, analyzed and designed that meets the function requirements presented. Parts have been specified, sourced and budgeted for acquisition. With this information the device/model is ready to be created.”

This project meets all the requirements for a successful senior project, including:

1. Having substantive engineering merit in both heat transfer and structural areas

2. Size and cost within the parameters of our resources

3. Being of great interest to the principal investigator

Note: In the final report, you will include a statement of how your device performs with respect to your stated requirements. For example:

The new design oil-separator was a success in both performance and design. It showed improvements over the benchmark in all four areas:

4. 20% more oil vapor was collected

5. There was a 10% improvement in air-flow

6. The cost was reduced by 30%

7. The manufacturing process was simplified from 6 to 3 processes.

ACKNOWLEDGEMENTS

Write: Company A sponsored this project…

Write: Person B mentored the principal engineer…

APPENDIX A – Analyses

Insert ‘green sheets’ here!

Write: APPENDIX B – Sketches, Assembly drawings, Sub-assembly drawings, Part drawings 08

08

08 08

08 APPENDIX C – Parts List and Costs

Write: Use your sketch (and drawings?) to do a ‘take-off’ of parts (types and numbers). Then start a list of these parts with some sort of identification, description, source (where to get/make it), cost (guess if you have to) and a comment space.

Part Ident

Part Description

Source

Cost

Disposition

Steel1

20’ stick 1” round

Pacific Steel

(800)xxx-xxxx

$32.00

Order 2/11

Fasteners

(20) ¼”x2” bolt, nut, wash

Local Hardware

$20.00

TBD

Motor

1HP induction w/ ½” shaft

McMaster Carr

#11-111111-1

$120.00

Donated

Cost Total:

$172.00

Notes: #1

Orient rolling direction lengthwise

APPENDIX D – Budget

This may be a separate document than the above list of parts. This could address other costs (e.g. labor) as well as timeliness. Aspects such as these are discussed in the area of project management. Write: APPENDIX E – Schedule; use a spreadsheet or software (MS Project), for the year.

Appendix F – Expertise and Resources

Write:

APPENDIX G – Evaluation sheet (Testing)

Write: Insert your data entry sheets for testing here. Also include sample excel sheets if you are using those for data entry and any calculations

APPENDIX H – Testing Report

Write: Insert your complete testing report here.

APPENDIX I – Testing Data

Write: Any raw data from your testing goes here. If you need to, scan your data entry sheets and insert here.

Appendix J – Resume

Write: You should be looking for a job anyway. Get a resume up to date and post it here. Do it now.

19

PARTS LIST AND BUDGET

SENIOR PROJECT TITLE _______________

ITEM ID

ITEM Description

Item Source

Brand Info

Model/SN

Price/Cost

Quantity

Subtotals

(US Dollars)

(or hrs)

($ / hour)

1

Container

REI

MSR

310R

15.99

1

15.99

2

Stove/Burner

REI

MSR

Whisperlite

54.99

1

54.99

3

Comustion Cmbr

Fabricate

3a

Stainless Sheet

Alaska Copper

SS304

20 gage

3a.1

SS Fabrication

shop/labor

15

3

45

115.98

Total Est.

Sheet1

PARTS LIST AND BUDGET
SENIOR PROJECT TITLE _______________
ITEM ID ITEM Description Item Source Brand Info Model/SN Price/Cost Quantity Subtotals
(US Dollars) (or hrs)
($ / hour)
1 Container REI MSR 310R 15.99 1 15.99
2 Stove/Burner REI MSR Whisperlite 54.99 1 54.99
3 Comustion Cmbr Fabricate
3a Stainless Sheet Alaska Copper SS304 20 gage
3a.1 SS Fabrication shop/labor 15 3 45
115.98 Total Est.

Sheet2

Sheet3

SCHEDULE FOR SENIOR PROJECT:

March 17-20 Finals

Note: June 4 Presentation

PROJECT TITLE:__________________

Note: June 9-12 Finals

ENG. TECH.:____________________

TASK:

Description

Duratioin

January

February

March

April

May

June

ID

(hours)

1

Proposal**

42

15-Feb

1a

Outline

2

4-Jan

1b

Intro

2

4-Jan

1c

Methods

2

4-Jan

1d

Analysis

6

20-Jan

1e

Discussion

4

25-Jan

1f

Parts and Budget

4

20-Jan

1g

Drawings

15

10-Feb

1h

Schedule

4

25-Jan

1i

Summary & Appx

3

15-Feb

2

Manuf Plan**

50

17-Mar

3

Device Constructed

100

15-Apr

4

Test Plan**

15

15-Apr

5

Device Evaluated

20

15-May

6

Project Report**

20

9-Jun

Total Hours Est:

247

Deliverables:**

Sheet1

SCHEDULE FOR SENIOR PROJECT:
March 17-20 Finals Note: June 4 Presentation
PROJECT TITLE:__________________ Note: June 9-12 Finals
ENG. TECH.:____________________
TASK: Description Duratioin January February March April May June
ID (hours)
1 Proposal** 42 14-Feb
1a Outline 2 3-Jan
1b Intro 2 3-Jan
1c Methods 2 3-Jan
1d Analysis 6 19-Jan
1e Discussion 4 24-Jan
1f Parts and Budget 4 19-Jan
1g Drawings 15 9-Feb
1h Schedule 4 24-Jan
1i Summary & Appx 3 14-Feb
2 Manuf Plan** 50 16-Mar
3 Device Constructed 100 14-Apr
4 Test Plan** 15 14-Apr
5 Device Evaluated 20 14-May
6 Project Report** 20 8-Jun
Total Hours Est: 247
Deliverables:**

Sheet2

Sheet3

EXAMPLE

SCHEDULE FOR SENIOR PROJECT:

NOTE: STUDENTS MUST MAKE THEIR OWN SCHEDULE!!!!!!!!!!!!!

March 1x-1y Wtr Finals

Note: June x Presentation

PROJECT TITLE:__________________

Note: June y-z Spr Finals

Engingeering Technician.:____________________ (your name)

Duration

TASK:

Description

Est.

Actual

January

February

March

April

May

June

ID

(hrs)

(hrs)

1

Proposal**

1a

Outline

1

2

4-Jan

1b

Intro

1

2

4-Jan

1c

Methods

1

2

4-Jan

1d

Analysis

1

2

15-Jan

1e

Discussion

1

2

15-Jan

1f

Parts and Budget

1

2

20-Jan

1g

Drawings

1

2

15-Jan

1h

Schedule

1

2

25-Jan

1i

Summary & Appx

1

2

30-Jan

subtotal:

9

18

2

Analyses

2a

Heat Trans=>Geo

1

2

2b

Stress Anal=>Geo

1

2

2c

Power Anal=>Geo

1

2

2d

Kinematic => Geo

1

2

2e

Tolerance => Geo

1

2

subtotal:

5

10

10-Feb

3

Documentation

3a

Part 1 drawing

1

2

3b

Part 2 drawing

1

2

3c

Subassembly 1

1

2

3d

Part 3 drawing

1

2

3e

Part 4 drawing

1

2

3f

Subassembly 2

1

2

3g

Part 5 drawing

1

2

3h

Part 6 drawing

1

2

3i

Subassembly 3

1

2

3j

Device drawing

1

2

3k

Kinematic Check

1

2

3l

ANSIY14.5 Compl

1

2

3m

Make Object Files

1

2

subtotal:

13

26

20-Feb

4

Proposal Mods

4a

Project Schedule

1

2

4b

Project Part Inv.

1

2

4c

Crit Des Review*

1

2

*Feb ??

subtotal:

3

6

28-Feb

7

Part Construction

7a

Buy Part 1

1

2

7b

Make Part 2

1

2

7c

Make Part 3

1

2

7d

Buy Part 4

1

2

7e

Make Part 5

1

2

7f

Make Part 6

1

2

7g

Take Part Pictures

1

2

7h

Update Website

1

2

7i

Manufacture Plan*

1

2

*Mar ??

subtotal:

9

18

5-Mar

9

Device Construct

9a

Assemble Sub 1

1

2

9b

Assemble Sub 2

1

2

9c

Assemble Sub 3

1

2

9d

Assemble Device

1

2

9e

Take Dev Pictures

1

2

9f

Update Website

1

2

subtotal:

6

12

20-Mar

10

Device Evaluation

10a

List Parameters

1

2

10b

Design Test&Scope

1

2

10c

Obtain resources

1

2

10d

Make test sheets

1

2

10e

Plan analyses

1

2

10f

Instrument Device

1

2

10g

Test Plan*

1

2

* April ??

10h

Perform Evaluation

1

2

10i

Take Testing Pics

1

2

10h

Update Website

1

2

subtotal:

10

20

30-Apr

11

495 Deliverables

11a

Get Report Guide

1

2

11b

Make Rep Outline

1

2

11c

Write Report

1

2

15-May

11d

Make Slide Outline

1

2

11e

Create Presentation

1

2

11f

Make CD Deliv. List

1

2

11e

Write 495 CD parts

1

2

11f

Update Website

1

2

11g

Project CD*

1

2

* June ??

subtotal:

9

18

Total Est. Hours=

64

128

=Total Actual Hrs

Note:

Deliverables:*

Sheet1

EXAMPLE SCHEDULE FOR SENIOR PROJECT:
NOTE: STUDENTS MUST MAKE THEIR OWN SCHEDULE!!!!!!!!!!!!! March 1x-1y Wtr Finals Note: June x Presentation
PROJECT TITLE:__________________ Note: June y-z Spr Finals
Engingeering Technician.:____________________ (your name)
Duration
TASK: Description Est. Actual January February March April May June
ID (hrs) (hrs)
1 Proposal**
1a Outline 1 2 3-Jan
1b Intro 1 2 3-Jan
1c Methods 1 2 3-Jan
1d Analysis 1 2 14-Jan
1e Discussion 1 2 14-Jan
1f Parts and Budget 1 2 19-Jan
1g Drawings 1 2 14-Jan
1h Schedule 1 2 24-Jan
1i Summary & Appx 1 2 29-Jan
subtotal: 9 18
2 Analyses
2a Heat Trans=>Geo 1 2
2b Stress Anal=>Geo 1 2
2c Power Anal=>Geo 1 2
2d Kinematic => Geo 1 2
2e Tolerance => Geo 1 2
subtotal: 5 10 9-Feb
3 Documentation
3a Part 1 drawing 1 2
3b Part 2 drawing 1 2
3c Subassembly 1 1 2
3d Part 3 drawing 1 2
3e Part 4 drawing 1 2
3f Subassembly 2 1 2
3g Part 5 drawing 1 2
3h Part 6 drawing 1 2
3i Subassembly 3 1 2
3j Device drawing 1 2
3k Kinematic Check 1 2
3l ANSIY14.5 Compl 1 2
3m Make Object Files 1 2
subtotal: 13 26 19-Feb
4 Proposal Mods
4a Project Schedule 1 2
4b Project Part Inv. 1 2
4c Crit Des Review* 1 2 *Feb ??
subtotal: 3 6 27-Feb
7 Part Construction
7a Buy Part 1 1 2
7b Make Part 2 1 2
7c Make Part 3 1 2
7d Buy Part 4 1 2
7e Make Part 5 1 2
7f Make Part 6 1 2
7g Take Part Pictures 1 2
7h Update Website 1 2
7i Manufacture Plan* 1 2 *Mar ??
subtotal: 9 18 4-Mar
9 Device Construct
9a Assemble Sub 1 1 2
9b Assemble Sub 2 1 2
9c Assemble Sub 3 1 2
9d Assemble Device 1 2
9e Take Dev Pictures 1 2
9f Update Website 1 2
subtotal: 6 12 19-Mar
10 Device Evaluation
10a List Parameters 1 2
10b Design Test&Scope 1 2
10c Obtain resources 1 2
10d Make test sheets 1 2
10e Plan analyses 1 2
10f Instrument Device 1 2
10g Test Plan* 1 2 * April ??
10h Perform Evaluation 1 2
10i Take Testing Pics 1 2
10h Update Website 1 2
subtotal: 10 20 29-Apr
11 495 Deliverables
11a Get Report Guide 1 2
11b Make Rep Outline 1 2
11c Write Report 1 2 14-May
11d Make Slide Outline 1 2
11e Create Presentation 1 2
11f Make CD Deliv. List 1 2
11e Write 495 CD parts 1 2
11f Update Website 1 2
11g Project CD* 1 2 * June ??
subtotal: 9 18
Total Est. Hours= 64 128 =Total Actual Hrs
Note: Deliverables:*

Sheet2

Sheet3

__MACOSX/._13 Report Guide 495.docx

15.10 DES ANALY GUIDE.docx

How to Create your ‘Design and Analyses’ Proposal Section

MET495A Senior Project: Yes, please use the outline numbers. And no, do not retain the italics. You must create your own words for your own proposal, using your skills from ENG310.

1. Design and Analyses

a. Approach: Proposed Solution

b. Design Description (picture, sketch, rendering)

c. Benchmark

d. Performance Predictions

e. Description of Analyses

f. Scope of Testing and Evaluation

g. Analyses (this is where you refer to each green sheet in Appx A)

i. Design Issue: 1, 2, 3, …

ii. Calculated Parameters

iii. Best Practices

h. Device: Parts, Shapes and Conformation

i. Device Assembly, Attachments

j. Tolerances, Kinematics, Ergonomics, etc.

k. Technical Risk Analysis, Failure Mode Analyses, Safety Factors, Operation Limits

Approach:

This is an introduction to your engineering approach. You can introduce your device terminology here, such as the term ‘collector’ or ‘drive train’. At this point you can discuss the important parameters of your device (e.g. gear train ratio, heat transfer coefficient, tolerance). These terms should relate to at least some of those in your Requirements section.

Now is a good time to prioritize your requirements and match them to some aspect of your design. Yes, by this time you really have to have an analysis plan. If you cannot think of an engineered design and equations to solve your problem, then either stop by and see us or get a new problem. You might think of an example like the RC drive train and how it is like the ‘gear train’ problems in your 418 class. Follow the example in your text and use your ‘requirements’ to ‘solve’ the problem. This ‘analysis’ is the first of many. There are other requirements that affect your solution, such as weight, torque or wear issues. You can describe your approach to solving this problem here.

Design Description:

This is the place where you can introduce the specifics of your design. A sketch can be quite useful embedded in this paragraph. Perhaps you have a couple competing designs that you can discuss. In some cases the motion of the device is important, and you may decide to show a few pictures of the device in various positions (e.g. a dump truck bed, fork-lift loader, die cast molder).

Benchmark:

A benchmark is useful if it can provide a characteristic and/or performance comparison. This performance number must be something of importance to the project (e.g. its weight, speed, strength, etc.). There may be no obvious similar device, but there is usually a comparable scenario. For example, your ‘lab project’ may feature a new concept/device. But there are other labs taught with similar equipment and tools that you can use to compare aspects of task times, data collection, etc. An important aspect of using a benchmark is that you specify exactly what it is. If it is a product, this means that you know its make, model number, cost and source (and provide a picture).

Performance Predictions:

We actually include ‘characteristics’ with ‘performance’ in this section. A prediction in an engineering sense includes a number value. For example, after drawing up an assembly in a 3D modeler, you can have it calculate a mass (and weight). Only numerical predictions are of engineering interest. And this reflects your value as an engineer. If you can predict performance, cost and timing: then you are valued at any company that proposes to do engineering work. The more you practice this: the better you get. We cannot emphasize enough the importance of this. You are absolutely required to predict the performance of your device. Then you are required to build it and test it for those exact predictions! Please fully engage (don’t fight it) in this process. This is a necessary part of graduating from our program. Again, only by doing this will you graduate!

Description of Analyses:

This is the place where you can discuss the order in which your analyses result in design parameters. You may have to compare different radiator designs to best meet a collection of requirements before you can design a control or interface aspect of the design. The number and order of your analyses is something you can plan ahead of time. Remember, you don’t need the ‘right’ numbers at first. What you need to do is convey to us (the instructors) that you have a clue and a plan to proceed.

Each of your ‘green sheets’ should be referenced from here. These calculation methods can be described, and the use of the outcome can be described. The sheets can cover anything from a strengths calculation to a comparison of power systems or the design of a gear train. You can analyze system issues (e.g. heat collector types/patterns) and include schematics. The possibilities are endless, so your ‘scope of effort’ serves a real purpose here.

Scope of Testing and Evaluation:

It is important to correlate your ‘requirements’ to your characteristic/performance ‘predictions’ and subsequent evaluation. There may be requirements that are not as important as others and will not be tested (e.g. sizes less that the allowed envelope). But others may be very important and must be predicted and tested (e.g. heat transfer, vehicle speed). This is a good time to consider if the necessary resources are available for testing the parameters you need. You can even start creating your ‘Test Data’ sheet (e.g. a spreadsheet?) so that you are aware of the scope of testing that will be needed. Also, you may consider support resources for testing (e.g. a race track, a foundry). All of this can reduce the risk of failure and promote synergy with your classmates.

Analyses:

The section contains the documentation of your complete analyses. You will not have it all done at once. But you can start listing the types of analysis you need, and plan for the use of the parameters that result from the calculations. Each analysis will include a group of associated information (e.g. Approach, Design, Calculated Parameter).

As a note, all of your actual calculations will be put in Appendix A. The only thing you will do here is to talk about them. Tell the story of how you engineered your device: calculation-by-calculation and number-by-number. You will also be able to discuss your drawings in Appendix B, because they use the parameters you calculate (e.g. the area from your heat transfer calculations will be documented on the drawing of the collector).

The engineering profession is regulated for safety by our government. This is common throughout the world for the good of citizens and subjects. It is therefore appropriate for us to recognize ‘best practices’ as we go about our engineering tasks. Try to find out the accepted practices for what you are trying to do. This is most relevant to safety critical projects (e.g. buildings, dams, bridges) but can be appropriate for any device that may involve a lawsuit. In the U.S. that includes about every object with which people interact.

Device: Parts, Shapes, and Conformation:

There will probably be aspects of your design that are not directly referenced to your analyses. This may be due to ‘artistic design’ (e.g. the shape of your device) or maybe the customer wanted a certain ‘look’ or ‘feature’. This is a place where you can address these issues and explain how you determined the shape of your device.

Device Assembly and Attachments:

Most devices will be assemblies made up of different parts. All our projects are different, so you have to decide how to communicate your project in the best way possible. If you are designing an attachment on a system (e.g. an adapter on a dynamometer) then you have the choice of including the model of the whole system (e.g. the whole dynamometer) or just the feature of the dyno to which your adapter fits. Please ask if you have any questions on this. In any case it is appropriate to discuss your parts, how they comprise the device, and how that device operates.

Again, it is appropriate for you to refer to your assembly drawings in Appendix B. You may not have made these drawings yet, but you can create a title and drawing number for them RIGHT NOW. Please do not wait for miraculous intervention. Our experience is that you will end up doing the work yourself. In fact you may consider creating a ‘drawing tree’ at this time.

Tolerances, Kinematics, Ergonomics, etc.:

All of our projects are different, so the above list of project issues may or may not apply to your situation. But in an attempt to address some common aspects of engineered projects, we choose to bring up at least these three topics.

Tolerancing is a prime aspect of tool design and many other engineering activities (e.g. gear trains, bearings and shafts, etc.). So if this is a primary endeavor of your engineering work: please discuss it here. The concept of ‘stacking tolerance’ may be important. The concept of ‘draft angle’ may be important. These concepts affect the evolution of your design and should be discussed.

Kinematics is another common area of interest. Any moving parts or device motion typically have requirements that force the design evolution. This includes the ASME Design projects (e.g. robots), the RC Mini Baja (e.g. cornering, suspension), and many other moving objects. A solid modeler may be your best tool to address tolerance issues. In any case, it is appropriate to discuss these issues here.

Ergonomics is another discipline that may be appropriate to discuss. Many devices are ‘operated’ by a human or have some ergonomic issue that can affect the design. This is an appropriate section to discuss aspects of ergonomics on your design.

Technical Risk Analysis, Failure Mode Analyses, Safety Factors, Operation Limits:

Risk analysis is a tool used to assure the success of the project. In a simple description, one identifies risks and then mitigates them. There are many types of risk, such as financial, scheduling, technical competency, and appropriate resources (human and physical). This section is intended to allow you to discuss the risks you perceive and how you intend to handle them.

Also, there are typically aspects of both safety in design (e.g. safety factor) coupled with specific failure modes. All possible modes of failure must first be identified. This is not typically a trivial task. Then the failure mode must be applied to the device and a ‘critical load’ scenario specified (e.g. specific loads on specific points of your device). Then ‘safety factors’ can be analyzed. Critical parts of your device may be identified with correlated safety factors. It is common, for example, in the aviation industry to have different safety factors for different parts of the aircraft (e.g. wings=2, struts=1.5). Again, it is appropriate to identify ‘best practices’ for your device and use appropriate procedures.

Finally, most devices will be operated. It is also common to impose limits on the operation of a device or assembly such that we avoid failure. In the aviation industry it is common to identify a ‘Utility Category’ of aircraft operations in which control of the aircraft is limited to +9 positive G’s and -3 negative G’s. This is an example of an operational limitation that is imposed on a device such that it performs within its capabilities. A ‘half-ton’ pickup truck is another example (e.g. don’t load it with a ton: bad things happen).

__MACOSX/._15.10 DES ANALY GUIDE.docx

15.10 INTRO GUIDE.doc

How to Create your Introduction

MET495A Senior Project: Yes, please use the outline numbers. And no, do not retain the italics. You must create your own words for your own proposal using your skills from ENG310.

1. Introduction Use numbers and letters (on left) if you want, Page #s are req’d Page 4

a. Motivation

b. Function Statement

c. Requirements

d. Engineering Merit

e. Scope of Effort

f. Success Criteria

Titles:

The title of your project should describe your engineered work. If you are solving a problem that will result in a device, then a description of the device is appropriate. For example: “R/C Mini Baja Drive Train”, describes the device of interest.

If you are part of a team, then you must start with a common title, and then use a colon followed by words describing your project. For example: “R/C Mini Baja: Drive Train”, vs. “R/C Mini Baja: Suspension”.

Motivation:

Your motivation is unique to your circumstances. Thus, you should offer a substantive narrative of your awareness, interest and involvement with some problem that can be addressed using engineering approaches. This section is usually a few paragraphs and sets the scene for introducing your problem.

Function Statements:

Unlike your 418 text, we do not want you to ‘number’ the functions of your device. Use simple grammar and construct a sentence that describes what your device must do. One sentence is usually sufficient. Begin the sentence with the words, “A device is needed that will….”, and then finish it. For example: “A device is needed that will accept power from the R/C car motor and transmit it to the wheels.” Another example is, “A device is needed that will suspend the frame of the R/C Mini Baja.”

If you are on a team, then list the function and requirements of the system first, and then repeat the process for your particular device. For example, the R/C Baja has to compete in a race, but the drive train transmits power (those are two separate functions). The Baja vehicle has to navigate an obstacle course (a requirement of a competing vehicle) but the drive train has to transmit power in a particular ratios (a requirement of the drive train project).

Requirements:

Requirements reflect the quality of engineering needed to solve the problem. If you have no requirements, then you do no engineering. Also, requirements allow for ‘optimizing’ a solution. A basic rule is that requirements define ‘compliance’ (e.g. regulations, rules, interfacing) or are quantitative.

For compliance, an example might be that the device must meet the ASME Design Competition rules. Or maybe a safety specification (e.g. ANSI, SAE, government) or application specification (e.g. military – MIL SPEC, company – Boeing spec) is appropriate.

Interfacing may be appropriate. For example, a lab project must use existing infrastructure (e.g. use existing equipment in MET314 or MET257). Or maybe the device is to be part of another system such as an existing R/C Mini Baja vehicle.

For quantitative requirements, you must use numbers.

Again, you must use numbers. TO REPEAT: YOU MUST USE NUMBERS IN REQ’s!

This is the most frequent failure of new engineers: they don’t want to use numbers! But the only way to ‘test’ your device is to set a goal (using numbers) so that when you test your device you can compare your measured performance (using numbers) to your predictions. Yes, you will set a goal (a requirement) and then predict your design’s performance (another number). Then you will build it and test it (getting yet another number). THIS IS ENGINEERING!

Everyone will have a cost requirement.

Everyone will have performance requirements.

Everyone will predict how much time it will take to complete your project.

So in your list of Requirements, please consider the following samples and scenarios:

· Cost: you will state a budget limit. That enable us to dismiss some projects immediately

· Compliance: please comply with any constraints related to rules, regulations, patents/legal issues, environmental conditions, customer needs, ethics, etc.

· Interface: please refer to any system interface, connectivity, resource use (e.g. lab), etc.

· Characteristics include: size, weight, shape, texture, kinematics, ergonomics

· Performance includes: movement, transport phenomena, capabilities

Requirements may be modified during the development of a proposal, and even after work has begun (it is called ‘negotiation’). But you must have an initial set of reasonable requirements.

What you cannot put into requirements (e.g. solutions): Materials, Objects, other devices….

TO REPEAT: NO SOLUTIONS IN YOUR REQUIREMENTS!

Optimization reflects the ‘engineering’ that ‘never ends’. If you have a weight requirement and you have a design that meets that number: is it a success? Well, if lighter is better, then you can always try to redesign and make it lighter. The same can be said of any performance requirement. Redesign it to make it go faster, higher, quicker, better, etc. We stop this evolution at some point due to time and cost. But this is not a 312 assignment! If you do a calculation and think you are done: then it is not engineering (maybe you could be a ‘manager’). Engineering is an open-ended process of design evolution to optimize device performance.

PS Always use bullets in your requirements. Always start the paragraph with a sentence.

Engineering Merit:

This is the area in which you describe the engineering that you will apply to solve this problem. You should be able to refer to particular equations from previous work. For example, if you are designing a solar collector, you may use a Qdot =h deltaT heat transfer equation to determine an appropriate area. If you cannot think of any engineering equation to use, then you are not doing any engineering.

Scope of Effort:

It is a good idea to consider the amount of work that you will be doing. Making a prosthetic hand is a very large project, and most likely not appropriate for our timing and resources. One finger joint may be more appropriate. Having 2 or 3 people on a Baja or ASME Design team is quite appropriate. If you have any questions or doubts: ask us!

Success Criteria:

Success of the project may be the performance of the device. Does it: interface, comply, perform, etc. Typically there are critical requirements that reflect ‘success’. The R/C vehicle is tested and completes all three challenges (e.g. sprint, slalom, motocross). Or the lab device performs as intended.

Success Scenario:

But the real success of a device may be in the intended application of the device. When the car is at the Baja completion and takes first place (success!). Or when a professor uses the lab device in a class and it performs (for them) as intended (success!).

RADD: Now we can talk about how the ‘Requirements’ drive the ‘Analysis’ to determine ‘Design parameters’ which you can then ‘Document’!

__MACOSX/._15.10 INTRO GUIDE.doc

15.10 METHODS GUIDE.doc.docx

How to Create your Methods and Construction

MET495A Senior Project: Yes, please use the outline numbers. And no, do not retain the italics. You must create your own words for your own proposal using your skills from ENG310.

3 Methods and Construction

a. Construction

i. Description

ii. Drawing Tree, Drawing ID’s

iii. Parts list and labels

iv. Manufacturing issues

v. Discussion of assembly, sub-assemblies, parts, drawings (examples)

Methods and Construction:

Projects vary widely in many regards such as type, size, shape and use. Here is a section in which you can discuss how you plan to create your device. Our use of the word ‘Methods’ is in part to be open enough for the various types of projects we see in the class. Sometimes a student will be working with an external agency and do absolutely no ‘building’ (e.g. hands-on machining) at all! But others will ‘construct’ their entire device, such as the ‘core boxes’ via 3D printer. This is the section in which you can describe your plan for making your device. The first paragraphs in this section should be used for an overall description of effort.

Description:

This is meant to be the launching point for describing the entire device. Notice that the ‘drawing tree’ and ‘drawings’ are the following sections. Here is where you describe the assembly or schematic of the project. You should discuss how the parts interact or support each other and contribute to the entire assembly. A numbering or identification scheme is appropriate to describe.

Drawing Tree and Drawing ID’s:

You have to construct a drawing tree and associated drawings. This is the section in which you go over every drawing, so you will be referring to Appendix B a lot. This may be a good time to describe the order in which you intend to make your parts. A common trait of a drawing tree is that the first parts to be made are at the bottom (the ‘roots’ of the tree) and as you go up the ‘tree’ you end up with subassemblies and finally the assembled device.

Parts list and labels:

You must keep track of your costs, parts, and acquisition of them. Thus all of your parts will have (this is not an option) identification labels. We do not care what they are. We only care that you can track them and answer any question we may have about them. Common questions about parts include costs, location, and readiness. If you have any questions about how to label your parts, we can point to any product what-so-ever and show you. But really, we will help you figure out a labeling plan.

Manufacturing Issues:

There are some aspects of a project that are quite predictable. For example, a fabricated part typically includes some joining by welding. It just turns out to be a very appropriate way to put things together. Our staff technician has already talked to you about access to his skills and timing. But this section is intended for you to describe the manufacturing issues that you see occurring in your project.

It is interesting to note that manufacturing covers a lot of ground. This could be ground-zero for joining, forming, processing and many other techniques. It could also be a place to discuss areas of required expertise that are not obvious, such as electronics (e.g. controls, transducers, actuators, etc.). Or this may be the section to discuss off-campus resources for creating your device. Whatever the need, this is where you can bring up issues relevant to the creation of your device.

Assembly, Sub-assembly, Parts, Drawings:

Now you can describe how each part is created and assembled into your device. There may be some interesting timing issues for both acquisition and making parts. There may be lead times that are discovered in getting all of the parts and processing together in a concerted effort. This is a great time to consider how you should go about making each part and in what order. It may be appropriate to write down a flow chart of all the parts from beginning to end. We intend that you will be in a better position to make a schedule if you have to put all this down ‘on-paper’ before hand.

__MACOSX/._15.10 METHODS GUIDE.doc.docx

15.10 TESTING GUIDE.doc.docx

How to Create your Testing Method

MET495A Senior Project: Yes, please use the outline numbers. And no, do not retain the italics. You must create your own words for your own proposal using your skills from ENG310.

4 Testing Method

i. Introduction

ii. Method/Approach

iii. Test Procedure

iv. Deliverables

Testing Method: (Introduction)

Since there are so many project functions out there, it means that there are many performance predictions to measure. This is the section where you discuss what you are going to measure, how you are going to measure it, and what you are going to do with the data.

This first paragraph or two should describe your primary test intentions. Again, there are many different needs, so all of the scenarios discussed here may not be appropriate to your project. We are just trying to make sure something is relevant to your project.

For example, a vehicle like an R/C could well need predictions of sprints, slaloms and obstacle course times. This may involve information on tracks, surfaces and configuration for predictive purposes, as well as the actual tracks for test purposes. One the other hand, if you have a new brake system for a race care, you may need to rent the whole track (this has happened!). We had one student design a few suspension systems for a vehicle and then organized the use of the county airport ‘apron’ to test for cornering characteristics, etc.

Please think about what your device is intended to do and reflect on what you may need to test your device against the predictions you make.

Method/Approach:

So start describing your approach to testing your predictions. List them. Discuss calculated parameters (e.g. speeds from distance and time). List the measurement tools you will need (e.g. scales, calipers, video gear, G-meters). Think it through and make sure your list is complete. Think of the test environment, such as temperature sinks or solar view. This can start a list of test sites and support environment.

Sometimes you actually have to make a ‘jig’ to test your part. Perhaps your device is suppose to support a load at some angle or under a specific thermal load. Making a ‘test jig’ can consume a significant amount of time and energy. It is good to plan this now.

Test Procedures:

Even the test procedures can be extensive. If you are renting a race track, you had best have at team in place with prior knowledge of what they need to do to acquire good test data. This means you have to make a test plan (e.g. operations) and have a secure data acquisition plan (e.g. test data equipment, forms or other support resources). All of this can be thought up now, even though you may not complete the ‘forms’, etc. You can at least list all of the items you can think of so that you have ‘place-holders’ on the books. There is an Appendix for all this.

Deliverables:

In the end you want to be able to discuss the performance of your device. You need to plan your testing up front so that you can test the device when it is ready. This allows you the opportunity to schedule necessary resources, make time to create test jigs, and otherwise make darn sure that all is in order when the time comes.

Specific deliverables are to be listed. If speed is a priority, the make sure it is accounted for in your test plan. All deliverables should be accounted for and the ‘calculated’ parameters should have the analysis already completed (e.g. a spreadsheet waiting for jus the input data).

This preparation for testing is the exact work that convinces a potential customer that you do indeed have the necessary training, interest and competence to do the work as you proposed.

__MACOSX/._15.10 TESTING GUIDE.doc.docx

15.12 495A Min Stds.docx

MET495A Minimum Standards for Senior Project Proposal

Each student will submit a Senior Project Proposal including:

· Title (with name, project title)

· Introduction (300 word minimum addressing engineering problem background, motivation, function statement, requirements, success criteria and scope)

· Methods (300 word minimum addressing: engineering discipline areas of interest, relevant equations and engineering optimization methods, benchmarks, a proposed engineering solution, and specific parameters that will be calculated and optimized).

· Analyses (300 words minimum addressing: at least two specific requirements that lead to specific calculations that lead to specific parameters that are specifically documented in the design solution, a scenario by which an ‘optimizing’ process for improving the device is described, and an initial comparison of calculations with your benchmark). Note: at least one dozen ‘calculations’ [on engineering paper] are required, and can be scanned and placed as an appendix. {495B a complete set of equations} Note: to be counted as a ‘calculation’, it must be accompanied by a sequence of Find, Given, Assume, etc., with the solution highlighted.

· Documentation (at least 300 words addressing: a description of your design, including a Drawing Tree, at least one Assembly Drawing, and at least three Drawing meeting ANSY14.5 compliance. {495B: a complete set of drawings}

· Budget (100 word minimum discussing and addressing: at least a dozen parts and/or system requirements [e.g. consumables] with supporting metadata [e.g. sources, costs, quantities] and a resulting total fund estimate for the project. Note: the Budget can appear as an appendix. {495B a comprehensive parts list and budget}

· Schedule (100 word minimum describing and addressing a Gantt Chart for the project. A Gantt Chart has Task Identifiers with engineering task level descriptions, duration, timing of duration, milestones [at least CDR, Parts Arrived, MDR, Construction complete, TDR and Final Report], and a final estimate of the total hours needed to complete the project. {495B a compete and comprehensive schedule}

· Conclusion (100 word minimum addressing: the salient results expected to support your claim of a successful project {minimum 3 major points].

· Acknowledgement (at least 50 words addressing: your acknowledgement of support from others such as CWU for the shop, mentors for advice, sponsors for funding, etc.)

· Appendix (addressing: calculations, drawings, pictures, budget, schedule, resume, etc.)

__MACOSX/._15.12 495A Min Stds.docx

Sr.Pr.file.1.docx

Torque Measurement on the Output Shaft of an Air Motor

By

Mohammed Alabdulmuhsin

Table of Contents INTRODUCTION 3 Motivation: 3 Function Statement 3 Requirements for this Project are: 3 Success Criteria: 3 Scope 3 Project Success: 4 DESIGN & ANALYSIS 4 Approach: Proposed Solution 4 Description 4 Benchmark: 4 Performance Predictions 4 Description of Analyses 5 Scope of Testing and Evaluation 5 Analysis 6 Approach: Proposed Sequence 7 Design: 1, 2, 3 … 7 Calculated Parameters 7 Device Shape: 7 Device assembly, Attachments 7 Tolerance, Kinematic, Ergonomic, etc. 8 Technical Risk Analysis, Failure Mode Analyses, Safety Factors, Operation Limits 8

INTRODUCTION

It’s important to see if a motor meets the specifications detailed by the company that manufactured the motor and meets its expected performance. Torque is an important factor of anything that rotates and spins, such as shafts, axles and spindles, and it’s an important mechanical quantity for the construction of mechanics. Knowing the motor output torque and RPM allows calculation of motor efficiency and pump efficiency separate from total system efficiency for this project. The system is a vane type air motor running on compressed air powering a gear pump to pump water. Compressed air delivers energy to the air motor, turning the pump.

Motivation:

Inspired by MET 314 Thermodynamics lab, system efficiency lab, this project was motivated by a need for a device that would measure the torque supplied by an air motor since a system nominal/application torque is important to know and understand.

Function Statement

Measure the torque on a rotating shaft.

Requirements for this Project are:

A device is required that would

· Weigh less than 10 lb.

· Capable to rotate at 3000 RPM. The RPM at max torque is 300 RPM.

· The cost of such a device is less than $100.

· The device construction will require using lab resources, such as metalworking cutting tools and welding.

· The motor has a power level of 1.8 HP,

· Capable to measure the stall torque of the motor, up to 56 in-lb.

· Device will couple to existing shaft with a diameter of 5/8” in.

· Measure torque to an accuracy of 0.1 in-lb

· Sensor output to data logger with sensitivity of 0.10 in-lb

· Must not expand length of lab setup, 5 inches/12.5cm (stay within mount plate footprint)

Success Criteria:

The real success of the device will be giving an accurate measurement of the torque delivered by the air motor with a sensitivity of 0.1 in-lb.

Scope

Will include a strain gage. The strain gage will serve as the primary sensing elements, it measure how much a piece of material will stretch per unit length, which will convert the applied torque into an electrical signal that can be filtered, displayed and recorded for extra processing.

Project Success:

Success depends on giving an accurate measurement of the torque delivered by the air motor, and initially to obtain a dependable torque measurement by measuring torque via strain gages and digital rotor telemetry.

DESIGN & ANALYSIS

Approach: Proposed Solution

Using a strain gauge attached to an arm held in place with precision bearings within a fixed housing and must be built onto the motor structure. It’s perhaps the most straightforward method by measuring both the torque the rotating speed. Using a strain gauge with a sensitivity of 0.1 in-lb. The arms and housing maximum length is 5 in and will be built into the air motor structure. The strain gauge and arms, attached to the mounting, will be capable of measuring the torque of up to 56 in-lb.

Description

The strain measurement will be converted to units of torque. Measuring the change of resistance, after appropriate calibration, one can measure the torque applied to the shaft. Using two arms mounted in the air motor, one arm will be used to measure strain using strain gauge and the other arm is to measure the calibration of a load and strain in the back of a motor. Both arms are connected to a fixed housing or mounted on the air motor.

Benchmark:

There are many approaches for measuring torque. A different approach to solve for the torque was made before, as a senior project, to measure the torque for the same air motor, but the device was not successful; the device is a coupling device that uses gears, and a fixed housing that was built to adjust on the motor structure. Unfortunately, the structure of the device elements, such as housing and gears are not sturdy. In this case only two gears were moving and in the same direction as the shaft, because they seems stuck to the rotating shaft. A senior student made the device, and it’s located at thermodynamics laboratory.

Performance Predictions

It is expected to have 0.10 in-lb torque measuring sensitivity, and with 0.05 repeatability with static load. Also, to have the ability to calculate torque, up to 56 in-lb. It is predicted that making the device will take two months after choosing the final design, with a budget of $100. The device and its parts must be sturdy to ensure an accurate measurement. Size is an important factor of performance and must not exceed 5 inches.

Description of Analyses

Dimensions for motor and bearing mounts.

The air motor used in this project (Fig.1) is a 1.8 HP air motor. It has a maximum airflow of 78 cfm and a maximum 3000-RPM. It also has a 5/8-inch shaft diameter, which will be coupled to the device.

Figure. 1

Scope of Testing and Evaluation

Beam analysis – strain gauge. Strain gauge range of value. Calibration load.

It is important to correlate your requirements to your characteristic/performance predictions’ and subsequent evolution. There may be requirements that are not as important as other and will not be tested, such as size. But others may be very important to predict and test, such as heat transfer, speed. This is a good time to consider if necessary resources are available for testing the parameters you need. You can even start creating your TEST DATA sheet, spreadsheet, so that you are aware of the scope of testing that will be needed. Also, consider support resources for testing, such as racetrack, a foundry. All of this can reduce the risk of failure and promote synergy with your classmates.

Analysis

The power that an air motor produces is simply the product of speed and torque. Air motor produce a specific power curve, with maximum power occurring at around 50 % of the free speed. (Fig. 2) The torque produced at this point is often referred to as the torque at maximum output.

Figure. 2

The output formulas:

Where, P = power [kW] --------------- M = torque [Nm]-------------------- n = speed [rpm]

At the present time, there are no known standards governing the operation of air motors in hazardous atmospheres.

Approach: Proposed Sequence

Design: 1, 2, 3 …

Calculated Parameters

Beam bending strain, beam dimension. Bearing Mounting tolerances/dimensions. Strain gauge predicts value.

Device Shape:

The device shape must be less than 5 inches. Two bearings with two arms mounted on the air motor (front and back) and will be connected to a housing or a base for the device.

Device assembly, Attachments

The device will be connected to an air motor. The two bearing and arms will be connected to the front and back of the motor. The base or the housing of the device will connect the two bearing together and with the motor. One arm will have the strain gauge; the other arm will hold a load to calibrate the strain measurements.

Tolerance, Kinematic, Ergonomic, etc.

Technical Risk Analysis, Failure Mode Analyses, Safety Factors, Operation Limits

6

__MACOSX/._Sr.Pr.file.1.docx