PART I Define, Conceive, Prove, Document
1.6 Capstone Design Process
The capstone design course(s) in the curriculum were included by your engineering program to respond to the ABET requirements for accreditation directly So, the cap- stone design course in your engineering curriculum was created to prepare you for engineering practice by placing you in an open-ended, real-world design project with characteristics similar to what you would experience if a company hired you Your professor(s) guide you through the process that they have developed for that purpose
However, capstone design is different in two different aspects The project time- line is first fixed by the start and the end of each academic period (semester or quar- ter) Some engineering programs have a capstone design course only during one academic period (10–14 weeks) Others have a full academic year experience The fixed timeline for all design projects creates some unique challenges in managing the capstone design project different from those encountered in the industry
The second difference is funding and resources There exist many different models at different institutions for funding capstone design projects Capstone design proj- ects come from various sources: industry, government labs, faculty research, design competitions, entrepreneurs, or an exercise design problem created for the class Regardless of the source, they have to conform to the requirements for the capstone design program, which is, at the minimum, those requirements listed in the ABET accreditation criteria document
This book describes a process I have used for the last 10 years, which has been refined every year and has proven to work well for projects from all the sources mentioned above The process is broken down into two parts to allow flexibility for engineering programs Engineering programs that only have one course covering their capstone design course can use Part I Engineering programs that have a full academic year design experience can use the entire book (Parts I and II) Consequently, the capstone design process time- line maps to the academic calendar, and the requirements are more specific
Figure 14 shows the process flow for Part I of the capstone design We have bro- ken down the capstone design process into two parts: Part I consists of defining the
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Define the Problem
Design Specifications Research
Project Plan Competitors
Conceive Design Solutions
Pugh and QFD Analysis Brainstorm
Critical Design Review 30xN Concepts
Considerations
Safety Ethics
Aesthetics Cost Operability
Ergonomics
Maintainability Regulations, Codes, Standards Prove
Prototype Engineering
Analysis
Testing Computer Simulation
TRIZ method
Patent Search
Document and Present (Preliminary Design Report)
Documentation Sustainability/
Environmental Considerations
FIGURE 1.4 Engineering Capstone Design process Part I diagram
18 Engineering Capstone Design problem, conceiving design solution concepts (as many as you can), using decision- making methods and expert and peer review to down-select to a small number of plausible solutions, prototyping/simulating and proving your selected design concept
Capstone design projects are open-ended design problems When the sponsor cre- ates a problem statement, they will be asked by your professor who is teaching the capstone to provide an open-ended design problem if possible Your professor for the capstone design course(s) will assess the problem statement and may ask the sponsor for adjustments to make the problem suitable for capstone in the context of scope, timeline, resource requirements, and level of difficulty The problem statement will have some realistic constraints such as aesthetics, safety, cost, ergonomics, environ- mental impact, operability, and maintainability Cost and financial considerations are always significant factors for capstone design projects Because the design problem is open-ended, the problem statement provided to you and your team will miss some critical information that your design team will need to research and define There will be many possible solutions to the design problem, some better than others Your team will need to follow a rigorous step-by-step (axiomatic) design process, as shown in the capstone design process figure To define the problem, you will need more informa- tion You can find that additional information in the following ways: researching online information and technical publications, searching through the patent databases, seek- ing advice from experts, consumer surveys, user surveys, and potential competitors
Once you have completed the problem definition step, you and your design team can describe and constrain the problem by completing a set of design specifications for your design problem The design specifications are central to many of the future steps in the design process, so your team must spend the necessary time and intel- lectual effort in creating a plausible set of design specifications The specifications should be as complete as you can achieve If you do not know the numerical values and ranges of some parameters initially, write them down and keep them in your design specifications to be determined (TBD) You will be able to fill those holes later in your design process It would be best if you began your efforts in design concept generation by meeting as a team and generating as many different but viable design concepts as you can produce during 30–60 minutes of meeting time Drawings and schematics are effective ways to capture your ideas Each member of the team should create at least 30 different design concepts Producing 30 different concepts seems like a daunting task, but you will be surprised by what you can achieve if you push yourself! Share your ideas with your team members Work together as a team to write down the pros and cons of each concept You will then use more formal methods to analyze your ideas and select a small number of design concepts to develop further
A formal part of the process is called the critical design review (CDR), where you present your selected two to four concepts to your peers, experts, sponsors, men- tors, and faculty in a group presentation You will receive a critique of your design concepts and feedback on improving your ideas With the additional information and feedback you have collected, you will refine your design choices further and create a model or prototype of your design
You will assess your prototype against your design specifications and document the assessment You will be required to produce a comprehensive design report for Part I You will provide the report document to your professor as well as to your spon- sors Ask them for comments and feedback We call that document the preliminary
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design report (PDR) The chapters that follow will describe details of each step in the process
Part II consists of building your design, testing it, redesigning, and repeating until a more optimal design is achieved In the end, you will document your design and present your work and accomplishments to your peers, professor(s), and sponsors The building of the design may involve an actual physical build, or it could be a com- puter design, process model, or software that your team will produce The building process details will be different, but you will need to prepare a detailed project plan to achieve your build development goals If you are building a physical device or sys- tem, you will need to purchase materials and parts to create your physical design In most cases, your physical build will not be the model’s actual build with the dimen- sions and materials that will be needed for full functionality Industry sponsors will generally prefer to build their versions of your design in-house to mitigate any poten- tial liabilities and incorporate your work into what they need
In your planning, you will have to allow for the administrative work required to process a materials and services purchase request and for availability and shipping time You will have to consult your professor for the course to follow your engineering department’s procedures or the institution has established for purchasing If you need to purchase software or plug-ins for existing software to create your model or soft- ware, you will need to follow the procedures for that type of purchase, which may be different from buying materials Your team should also pay attention to your skills in manufacturing, modeling, and software development Do you have the needed skills to build your design? Do you have access to people who can help your team make what you have designed? Do you have the resources that you need, such as funding, tools, software, machines? If you cannot create it, then you may have to redesign it
Once you have achieved a build of your design or model, you need to verify that it meets your design specifications You validate your design by creating a set of experiments or tests to test your design against a range of parameters from your design specifications If there were any gaps in your design specifications, now would be a good time to revisit those and establish values for those If you still cannot define those parameters, then maybe they should be eliminated from your design specifica- tions You may need to perform some tests to determine or refine your design speci- fications’ numerical values You will need to carefully plan your test engineering activities and limit your testing to those that will produce helpful information for your redesign and optimization work Don’t engage in a test because you know how to do that test from your previous courses Analyze what you need to test and how you would perform that test Do you need to test for compliance with any regula- tions or codes concerning your design? Many standard testing methods are published through national professional engineering societies Make sure you follow those test- ing procedures if appropriate for your design
From your test engineering procedures, you will collect data that you can ana- lyze for the performance measurement of your design The results of the analysis should guide you in optimizing your design or correcting errors You will have to repeat the cycle of build-test-redesign as many times as necessary to achieve a good design Many of my past projects have ranged from two iterations to 150 iterations It depends on the scale and complexity of the design and its build Figure 15 shows the process flow for Part II of the capstone design
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Design Build
Assembly/Integration Customer/User
Interface
Software Development
Project Management
Test Engineering
Standards Poka Yoke
Success/Failure Methods
Cost Management
Considerations
Safety Ethics
Aesthetics
Cost Operability
Ergonomics Maintainability
Regulations, Codes, Standards Redesign
Customer/User Satisfaction Optimization
Financial/Resource Analysis Cost
Project Management
Manufacturing/
Process Implementation
Financial Analysis/
Cost Management Documentation
Function
Document and Present (Final Design Report and
Design Showcase) Sustainability/
Environmental Considerations
FIGURE 1.5 Engineering Capstone Design process Part II diagram
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