Design Constraints

Written Report Format

Product Design Constraints and Requirements

Design Engineers must consider a multitude of technical, economic, social, environmental, and political constraints when they design products and processes.

There must be clear evidence in your design project that you have addressed the constraints that are relevant to your project.

Effect of Constraints

Better Designs

Design Changes

Design Changes

Constraint Limits

Functional Constraints• Overall Geometry – size, width, space, arrangement• Motion of parts – type, direction, velocities, acceleration,

kinematics• Forces involved – load direction, magnitude, load, impact• Energy needed – heating, cooling, conversion, pressure• Materials to be used – flow, transport, properties• Control system – electrical, hydraulic, mechanical, pneumatic• Information flow – inputs, outputs, form, display

Safety Constraints

• Operational – direct, indirect, hazard elimination• Human – warnings, training• Environmental – land, sea, air, noise, light, radiation,

reaction, transport

Quality Constraints

• Quality assurance – regulations, standards, codes• Quality control – inspection, testing, labeling• Reliability – design life, failures, statistics

Manufacturing Constraints

• Production of components – factory limitations, means of production, wastes

• Purchase of components – supplier quality, reliability, quality control, inspection

• Assembly – installation, foundations, bolting, welding• Transport – material handling, clearance, packaging

Timing Constraints• Design schedule – project planning, project control• Development schedule – design detailing, compliance tests• Production schedule – manufacture, assembly, packing,

transport• Delivery schedule – delivery date, distribution network,

supply chains

Economic Constraints• Marketing analysis – size of market, distribution, market segments• Design costs – design team computing, information retrieval• Development costs – design detailing, supplier costs, testing costs• Manufacturing cost - tooling, labor, overhead, assembly, inspection• Distribution costs - packing, transport, service centers, spare parts,

warranty• Resources – time, budget, labor, capital, machines, material

$

Ergonomic Constraints• User needs – type of operation, instructions, warnings• Ergonomic design – man-machine relationships,

operation, height, layout, comfort, lighting• Cybernetic design – controls, layout, clarity, interactions

Ecological Constraints• General environmental impact – impact on natural

resources, social resources• Sustainability – political and commercial consequences,

implications for following generations• Material selection –solid, liquid, gas, stability, protection,

toxicity• Working fluid selection – fluid, gas, flammability, toxicity

Aesthetic Constraints• Customer appeal – shape, color, texture, form, feel, smell,

surprise and delight features• Fashion – culture, history, trends• Future expectations – rate of change in technology,

trends, product families

Life-Cycle Constraints• Distribution – means of transport, nature and conditions of

dispatch, rules, regulations• Operation – quietness, wear, special uses, working

environments• Maintenance – servicing intervals, inspection, exchange and

repair, cleaning, diagnostics• Disposal – recycle, scrap

Legal/Ethical Constraints• Regulations – OSHA, FAA, FDA• Ethics – public safety, health, welfare and integrity• Intellectual Property – patents, trademarks, copyrights

Project Reports

• MidTerm report

• Oral report

• Final Report

MidTerm Report

• Should describe MidSemester progress

• Think of it as a start on your final report

• Introductory and background material and project description material will remain the same

Technical Communication Format(MAE 451)

• “Double Five”

• Include technical discussion

• Include business topics as appropriate

Report Format

• Summary

• The Problem

• Scope and Goals

• Solution

• Results

• Conclusions

• References

Summary

• Summarize the project and your work

• Don’t summarize the report

• Briefly introduce the problem

• Summarize the solution and conclusions

• Typically half a page in length

The Problem (Introduction)

• Introduce the design problem here

• Background information on the company or research/laboratory area

• What is the project?

The Problem (Introduction)• Introduce the design problem here

• Background information on the company or research/laboratory area

• What is the project?

• Why is it of interest?

• What are constraints or requirements that the solution must satisfy

• Briefly highlight the contents of the report

Scope and Goals

• Very specific description of your design project and expectations

• What specifically was to be accomplished?

• Are you part of a team?

• Are you continuing a project?

• What is needed to finish the project?

Solution

• Select Titles and Subtitles for your project

• This is the place to describe the details of your work process and issues encountered

• Discuss constraints and your management of them - a special subsection would be best

• Include figures, graphs and photos

• Large amounts of information should be in an appendix at the end of the report

Results

• Describe the results of your work including your resulting design

• Include figures, drawings etc. as appropriate

• Comment on the quality of your technical results and design

Conclusions

• Have you achieved the goals of your design?

• Is the problem completely solved?

• Is there continuation after the semester ends?

• Will the project have to be continued by another group?

• If more work is needed, describe it carefully and suggest a completion schedule.

References

• References make your work credible

• Back up all of your facts with references

• Indicate references for any previous work on your design project

• Indicate references for similar projects by others

• Use references for any technical approaches used in your solution

• State your references completely

Report Format

• Summary

• The Problem

• Scope and Goals

• Solution

• Results

• Conclusions

• References

Comments on Figures

• Figures are best inserted directly in the text

• Insert figures right after they are discussed

• Clearly number each figure and be sure to discuss the figure by number

• As an alternate - place all the figures together at the end of the report

Just to Summarize

• Think about CONSTRAINTS and report on their effect on your design

• Make your report professional

• Think of the MidTerm report as a start on your final report

• Make use of the suggested report format