EPICS Design Process Guide
Contents
1. Access Input Output Capabilities 2 l 2 Cost 2 3 1 2 Total sum weight rank 37 36 67 Example 2 Weights Potential Solutions Catena tor 1 high 5 low Steel Aluminum Wood Comparison Strength 2 1 2 3 Weight 3 2 1 3 Appearance 4 3 2 1 Ease of use 1 3 2 1 Cost 3 3 2 1 Total sum weight rank 32 23 23 Proof of Concept Rapid Prototype Besides using a decision matrix to help you analyze potential solutions another option is to develop a proof of concept or rapid prototype in order to better understand the potential solution A proof of concept or rapid prototype will allow you to test the feasibility of the potential solution both in terms of the ease of implementation and its functionality These are different from the prototype that will be developed during the detailed design phase in that a proof of concept or rapid prototype is not intended to be close to a final product The only purpose of the proof of concept or rapid prototype is to test the feasibility of a design or an aspect of a design The key to developing a proof of concept or rapid prototype is to get to a working model quickly It doesn t have to be perfect as long as it adequately demonstrates how the potential solution would work in the final project In addition to allowing you to better analyze a potential solution a proof of concept or rapid prototype also serves as a communication aid wi2. Copyright 2008 EPICS 17 9 14 2008 EPICS Design Process Comparison Criteria 1 2 Criteria 2 1 Criteria 3 5 Once you have your matrix set up you will need to go through an evaluate each of the potential solutions against the criteria You can do this by ranking them for each criteria assigning a value to them based a scale you set up or classify them in any other way that works for you The objective is to have some way to compare each of the potential solutions and decide based on the weights assigned to each criterion which option is best The difficulty lies in deciding how to weigh each of the criteria selected This is because all of the criteria are interrelated For instance you may need to select a particular material to use for the construction of a kiosk One of your functional criteria may be the strength of the material This may also relate to safety since the kiosk will have to be strong enough to perform its function without injuring anyone However as the strength of the material increases the cost of the material also increases The choice of material used to construct the kiosk will also affect the aesthetics as well as the manufacturability since stronger materials are often harder to work with You will need to sort through how each of the criteria you develop affects other criteria in order to determine your weightings At this point it may be important to meet wit
3. HRIEAL Codes or Standards Professional conduct Are there any health or safety issues Risk of physical injury Hearts Risk of emotional or mental harm Can be used for unintended uses Does your design unnecessarily exclude certain users Dexterity requirements Inclusiveness ie Cognitive requirements Non adaptability Are there any manufacturability constraints Manufacturability Ease of production Accessibility of materials Are there any political issues Political Local state or federal codes policies and standards Relationships of power between or within organizations Are there any social issues Social Discrimination based on gender age race ethnicity culture socio economic status Impact on community s way of life Are there any sustainability issues Sustainability Maintenance requirements Ease of maintenance Availability of materials needed for repairs Are there any usability issues Usability Clarity of user interface Clarity of instructions Training requirements gt Examples of Decision Matrices Example 1 Weights Potential Solutions Criteria for 1 high 5 low Microcontroller PLD Discrete Logic Comparison Volume Control Current Tran 4 2 1 3 Physical 4 2 1 3 Size Ease of Development 2 Number of 1 1 2 3 Instructions Memory 3 1 2 3 Copyright 2008 EPICS 19 9 14 2008 EPICS Design Process
4. Advisor and EPICS Admin Approval After you have completed the project and are ready to deliver it you must first get the project partner s your advisor s and the EPICS administration s approval and complete the delivery checklist This is needed to ensure that the project is safe and ready for being deployed to the community In order to get the EPICS administration s approval you will need to set up a meeting with either Carla or Professor Oakes at which point you will demonstrate your completed project Deliverables All documents required for this phase should include a cover page listing the team and project along with a title describing what the report is the date it was created and all authors who contributed to it Within the report itself all pages should be numbered and there should be a header containing the title of the report 1 Completed Project This deliverable needs no explanation 2 User Manual As discussed above you will need to produce a user manual for your project Your manual should include a Instructions for using all features of the project b Troubleshooting tips c Contact information for any problems 3 Delivery Checklist The delivery checklist is a one page document that EPICS requires to be completed for every project delivered It ensures that everything is in order before placing the project out in the community The form can be accessed at http epics ecn purdue edu forms formname d
5. The main result of this step in the detailed design phase will be the diagrams drawings schematics etc needed to construct the prototype of the project The design of each of the components should be outlined in design records You will also likely need to add additional specifications to your list as you work through the detailed design of your project These specifications will deal mostly with the implementation of the design and will be specific to the project 3 Prototyping of Project After you have developed and analyzed your designs on paper it s time to develop a working prototype This will require you to select materials for the implementation and may also force you to make modifications to your original designs At the end of this step you should have a fully functioning prototype 4 Field Testing User Feedback One of the most important steps in this phase of the design process is get feedback on your prototype from the project partner and or the users During this process you will likely find a number of problems with your current design as well as additional functionalities that are needed These can all be addressed when you develop the final version of the design that will be delivered to the project partner 5 Design for Failure Mode and Effect Analysis DFMEA As part of this phase in the design process you will need to conduct a DFMEA on your design This is a technique to explore the possible ways your project mi
6. culture socio economic status etc x Sustainability issues related to the long term use of the design including maintenance and repair xi Usability issues related to the overall ability of a user to perform the tasks the project was designed for f Discussion of how the information gathered and new insights developed during this phase of the design process will impact the future phases Project Detailed Design Phase The following are a set of guidelines to help you work through the Detailed Design phase You will need to have completed all necessary tasks from the project conceptual design phase before proceeding with this phase If this phase was completed previously you will need to review the design documents from that phase As you work through this phase you should touch on each of the major steps listed below Some aspects of each step may not be directly applicable to your project but all projects will have some work related to each of the following steps 1 Bottom up Development One of the differences between the functional decomposition and specifications development tasks and the design and implementation of the actual system is that with the previous steps you start from the overall system and gradually get more specific with the design and implementation you start from the specific and build up to the entire system This is necessary since for most projects the system does not exist without the components Software
7. have been shown to not work Reverse Rearrange would an opposing idea give you additional information or can you interchange the key elements of the idea to form a new one Looking at the elements in your list with these possible actions in mind can lead to the generation of new ideas More information on brainstorming can be found in section 4 6 Copyright 2008 EPICS 16 9 14 2008 EPICS Design Process of Lima and Oakes Service Learning Engineering in Your Community starting on page 106 Many have found that In order for brainstorming to be most effective it is helpful to have rules to guide the brainstorming session In the book Making Things Happen Scott Berkun recommended the following rules 1 Yes and This requires each person to listen to the other ideas and then if at all possible to build on them The intention is to keep things moving positively and to develop a habit of listening to others in order to help them with their ideas instead of just waiting to say your own 2 Be committed to what you are saying Do not follow what you are saying with an apology or by remarking that your idea is dumb or lame 3 No blocking questions Questions put ideas and the people asking them on the defensive Instead look at how you can take the idea and move it in a positive direction 4 Make the other guy or girl look good Rewards should go to the people who help amplify express or draw out the b
8. of what a basic functional decomposition might look like Copyright 2008 EPICS 8 9 14 2008 EPICS Design Process Functional Decomposition Skeleton Primary Function Zo NX Sub function Sub function Sub function Sub function Functional Decomposition Example 1 Talkie Board Caid User Interface Mode Selection Sound System Identification Controls Identify Identify Present accessible Change between Record Access specific when cards in to record play put play messages cards cards viewable teacher on take off power messages dynamically placed or manner cards to on off removed student Functional Decomposition Example 2 Allow people to volunteer over the internet Allow users to Allow volunteers Allow staff to access site though to select events assign volunteers username and and hours to events password Different Username and privileges for password creation volunteers and and maintenance staff 2 User Interaction Another key step in developing the specifications for your project is to determine how a user will interact with the project The user interface is a key component to Copyright 2008 EPICS 9 9 14 2008 EPICS Design Process any design since this will be the only way someone will be able to make use of the project Therefore y
9. of the project both in terms of the external and internal design ii Economic issues related to the cost of the project including the cost development production maintenance and in terms of both monetary and time costs iii Environmental issues related to ecological effects as well as effects on the working environment of the users iv Ethical issues related to the professional responsibility intellectual property adherence to standards and codes etc v Health and Safety issues related to the risk of harm or injury to the user vi Inclusiveness issues related to how the design affects who is able to use the project vii Manufacturability issues related to the construction of the design viii Political issues related to hierarchies of power within an organization or between organizations ix Social issues related to gender age race ethnicity culture socio economic status etc x Sustainability issues related to the long term use of the design including maintenance and repair xi Usability issues related to the overall ability of a user to perform the tasks the project was designed for Fielded Project Report 1 Evaluate performance of fielded project How is the project performing Does it still meet the needs of the project partner Should the design continue to be deployed as is or is redesign or retirement required 2 Determine resources required to support and maintain the project Does the
10. of the components of your project All of your designs for the various components of your project should be documented in design records The design records should include a b Explanation of the purpose of the component including its intended functionality Explanation of how it interacts with the other components of the system including the inputs received and outputs generated by the component Schematics diagrams drawings etc showing the design of the component Discussion of decisions made during the design of the component including any assumptions made 2 Prototype One of the deliverables for this phase of the design process is a functioning prototype of the project It should be used to get feedback from the project partner and or the users on the design 3 Detailed Design Report The detailed design report is the main document for this phase of the design process It should contain a summary of all the steps completed during this phase In addition it should include the following elements a Po egg ee Table of contents to all documents created during this phase of the design process Title Author s Date Location Brief Description Description of the overall design approach for the project as well as descriptions of each of the components and how they all interact Pointers to all of the design records outlining the detailed design of each of the components Description of the prototyp
11. of the overall approach chosen for the project and how each chosen solution will meet the specifications laid out for the project Refer back to the explanation of how the factors listed below affected the Project Identification phase and explain how and why the factors affecting the specifications development phase are similar or different identifying the factors that are most important for this phase and how they relate to each other i Aesthetic issues related to the physical appearance or appeal of the project both in terms of the external and internal design ii Economic issues related to the cost of the project including the cost development production maintenance and in terms of both monetary and time costs iii Environmental issues related to ecological effects as well as effects on the working environment of the users Copyright 2008 EPICS 22 9 14 2008 EPICS Design Process iv Ethical issues related to the professional responsibility intellectual property adherence to standards and codes etc v Health and Safety issues related to the risk of harm or injury to the user vi Inclusiveness issues related to how the design affects who is able to use the project vii Manufacturability issues related to the construction of the design viii Political issues related to hierarchies of power within an organization or between organizations ix Social issues related to gender age race ethnicity
12. project require any fixes Who on the team is prepared to provide service for the project is needed Is additional training required References Berkun S 2008 Making Things Happen Mastering Project Management Sebastopol CA O Reilly Media Inc Dym C L and P Little 2004 Engineering Design A Project Based Introduction New York NY John Wiley amp Sons Inc Horenstein M N 1999 Design Concepts for Engineers Upper Saddle River NJ Prentice Hall pp 21 24 Lima M amp Oakes W C 2006 Service Learning Engineering In Your Community Okemos MI Great Lakes Press Inc Voland G 2004 Engineering by Design 2 Edition Upper Saddle River NJ Prentice Hall Copyright 2008 EPICS 34 9 14 2008
13. should have a design record Included in the design record should be a b c d Decision Matrix Description of all potential solutions compared Description and rationale for comparison criteria Reasoning for selecting the chosen solution 2 Proof of Concept Rapid Prototype If you created any proofs of concept or rapid prototypes during the conceptual design phase they should also be accompanied by a design record Each design record should include a b c d A description of the solution being tested Purpose for creating the proof of concept or rapid prototype to test the solution Detailed description of the development of the proof of concept or rapid prototype Discussion of the results of testing or other information gathered 3 Conceptual Design Report The conceptual design report is the main document for this phase of the design process It should include a summary of all steps completed during the phase with an in depth discussion of the chosen solution s The document should include the following elements a Table of contents to all documents created during this phase of the design process Title Author s Date Location Brief Description Summary of all decisions made with references to design records for decision matrices Summary of all proofs of concept or rapid prototypes created the information gathered from them and references to all design records created Detailed discussion
14. 04 e Physical space allocation or dimensional requirements weight limits material characteristics energy or power requirements e Functional Operational acceptable vibration ranges operating times input output requirements e Environmental moisture limits dust levels intensity of light temperature ranges noise limits potential effects upon people or other systems that share the same environment e Economic limits on production costs depreciation operating costs service or maintenance requirements existence of competitive solutions in the marketplace e Legal governmental safety requirements environmental or pollution control codes production standards e Human Factors Ergonomics strength intelligence and anatomical dimensions of the user Example Criteria Height of the user interface Access speed Memory capacity Tipping force Tensile strength 5 Customer Specifications Development Now that you have your criteria for judging designs and an idea of what has already been done you are ready to create the customer specifications for your project Specifications are the values associated with the measureable criteria developed before that is the values you are aiming to meet For instance one of your criteria might be the access time for a database query Your specification would then be the actual time you want that query to take What quantifiable and measurable specifications will be used to evaluate designs For
15. EPICS Design Process Conduct needs assessment Describe social context in which project partner operates Identify community partner contact Identify outcomes or deliverables Determine duration of the project Identify benchmark products prior art Identify users and beneficiaries Define the customer requirements objectives constraints Project Charter Project Partner and Advisor approval required prior to moving to next phase Specification Development Phase Tasks Deliverables Complete high level Functional Decomposition of project Define how users will interact with project User Analysis Compare to benchmark products prior art Develop evaluation criteria Develop customer specifications and get project partner approval Complete full Functional Decomposition Functional Decomposition Develop design specifications Project Specification Document Project Partner and Advisor approval required prior to moving to next phase Conceptual Design Phase Tasks Deliverables Generate potential solutions Customer Specifications Document Complete Decision Matrices Proof of Concept Rapid Prototype Choose best solution Project Conceptual Design Report Project Partner and Advisor approval required prior to moving to next phase Detailed Design Phase Tasks Deliverables Develop using bottom up implementation freeze interfaces Desi
16. You will need to have completed all necessary tasks from the Project Identification phase before proceeding with this phase If this phase was completed previously you will need to review the design documents from that phase As you work through this phase you should touch on each of the major steps listed below Some aspects of each step may not be directly applicable to your project but all projects will have something related to each of these steps The main purpose of the specifications phase is to transform the customer requirements which may be vague and unquantifiable into customer and design specifications which are concrete and quantifiable The purpose of this is to arrive at a set of criteria to determine whether your project is successful or not There will be two major tasks in this phase the development of the customer specifications which are presented to the project partner for approval and the development of the design specifications which are more detailed and outline all of the specific functions and specifications for the project The development of the design specifications is simply a continuation of the customer specifications development process 1 Basic Functional Decomposition The first step in translating the customer requirements into specifications is to identify all of the major functions the project will need to perform This is done through a technique called a functional decomposition Based on the functional s
17. analysis are simulating the response of a circuit using circuit simulation tools conducting an experiment to obtain data or deriving simple equations of motion to determine expected forces Design If more than one solution exists and if deciding upon a suitable path demands creativity choice taking testing iteration and evaluation the activity is most certainly design It can include analysis but it also must involve at least one of these other elements Reproduction Process of recreating something that has already been designed For example copying oscillator circuit from an electronics book and substituting resister values to set the frequency is an example of reproduction not design Characteristics of Good Design vs Bad Design Horenstein 1999 Good Design Bad Design 1 Works all of the time 1 Works initially but stops working after a short time 2 Meets all technical requirements 2 Meets only some technical requirements 3 Meets cost requirements 3 Costs more than it should 4 Requires little or no maintenance 4 Requires frequent maintenance 5 Is safe 5 Poses a hazard to the user 6 Creates no ethical dilemma 6 Fulfills a need that is questionable Copyright 2008 EPICS 2 9 14 2008 EPICS Design Process Design and the Design Process Dym and Little 2004 define engineering design to be a thoughtful development of objects that perform desired functions within given l
18. ase of the design process will be taking the ideas you had in the conceptual design phase and transforming them into an actual design for your project You should design each of the subcomponents of the project following the bottom up implementation described above This is one of the most challenging aspects of the design process because it will require you to use knowledge and skills from a number of different areas First of all you will be required to use the disciplinary knowledge you have gained through your formal education This knowledge will take on different forms depending on your major and how far along you are with your degree You will also need to use less formal disciplinary knowledge possibly acquired during internships or other practice in order to successfully complete your design However you will also be required to obtain new knowledge during the design of the project This may be new knowledge that is directly related to your discipline or it may be something completely different For instance you may be an electrical engineer working on a circuit but you don t have background using a specific type of chip You will need to do research into how to use that chip effectively in order to design your project Likewise you may be an educator working on the content for a software project In order to successfully complete the design you may need to learn some basic programming in order to add your content into the program
19. ay not be directly applicable to your project but all projects will have something related to each of these steps The goal of the Project Identification phase is to better understand the need that your project partner has asked you to help address and begin to translate the statement of need expressed by the project partner into tangible and specific requirements that will guide your design Although it is tempting to devote very little time and attention to this phase to get to the real work of your project the success of your project depends on how well you complete this phase The knowledge and insight that you learn from this phase should be summarized in the Project Charter Both the Project Partner and Team should approve the Project Charter as the guiding document for the overall project It is important that the new team members read the Project Charter to gain an understanding of the motivation It is also helpful for team members to review the document throughout the design to prevent scope creep It is natural for both the customer and designers to want to add functionality to the design as the progress inspires new ideas However it is important that any changes to the scope be deliberate and that everyone understands and agrees to the impact of the changes The following are a set of tasks to help you begin your project and work through the Project Identification phase As you work through this phase you should touch on each o
20. correctly sensor sensor is offset detecting laser 6 mo nted test before release 36 photodetector not display has been mount with sturdy sensor sensor is offset detecting laser 6 jarred brackets specific mirror not improper Mirrors eye from functional must be 7 attachment violent DSA and 112 reattached handling P Mi separate from mproper maintenance and irrors rod mirror breaks 7 attachment violent checkup 56 handling component r laser beam loses maintenance and Mirrors poor reflection FE 5 fatigue scratch on 60 some visibility SEC checkup wear and tear Maze reduce functionality tilting maintenance and Components broken of display 2 mishandling of checkup at kiosk mirror cannot be manipulated rod improper usage by maintenance and Rog Knob penned needs to be 6 patrons checkup 2 replaced improper usage by maintenance and Rod Knob broken rod safety hazard 9 patrons checkup 144 os ia design so the rods Rod Knob See lle safety hazard 9 Re tar do not stick out of 36 g by play kiosk very far improper usage by Rod Knob knob falls off rod cannot be easily 4 patrons improper maintenance and 80 turned checkup attachment the rod can be improper usage by Rod Knob stopper breaks moved in and out of 4 patrons improper mp and 64 display attachment P components break improper usage by Rod Knob stopper breaks rendering project 8 patrons improper pue and 128 unfunctional attachment P improper usage by R
21. ct partner may describe existing products that address some aspect of the need but have shortcomings that limit their effectiveness to meet their particular needs or describe a particular solution to the need as part of their needs statement It is important to separate the need from the solution when conducting the needs assessment Describe Social Context in which project partner operates The social context of your community partner reflects a complex matrix of variables social cultural economic political and or organizational that influences the operation of your project partner and how your project partner responds to the particular social issue outlined in their stated mission and goals At all stages of the design of your project these social facts and your perception or understanding of them constitutes the larger social reality into which your design solution will be embedded Therefore it is important that you be able to describe and begin to understand the social context of your project partner this understanding is a critical starting point in being able to assess the implications of any design decisions you make and how these decisions will impact the stakeholders in the project The following are important questions and factors to consider in writing out your description of the social context of your project partner Understanding the social challenge addressed by the project partner and the client served What is the mis
22. d to card User Analysis i Constraints Benchmarks Deliverables All documents required for this phase should include a cover page listing the team and project along with a title describing what the report is the date it was created and all authors who contributed to it Within the report itself all pages should be numbered and there should be a header containing the title of the report 1 Functional Decomposition The first deliverable required for this phase of the design process is the functional decomposition You are required to perform a functional decomposition of your project and produce a design record outlining that decomposition You may present the decomposition in any way you choose outline table diagram etc but you must include a Hierarchy of functions b Explanations for functions identified including a justification for inclusion specifically what that function does and how it relates to other functions c Discussion of functions not included and justifications for not including them 2 User Analysis A user analysis should be carried out during this phase of the design process and should be documented in a design record Your record should include the following elements a Characteristics of the users age gender mental and physical capabilities etc b Impact on the design Copyright 2008 EPICS 14 9 14 2008 EPICS Design Process 3 Customer Specifications Document The customer sp
23. development can be different in that the structure of the main program can be set up but it still will not function until each of its subcomponents is developed One aspect that is critical to developing a functioning system and often needs to be decided on early in the design is determining how each subcomponent of the system will communicate with each other This is called freezing the interfaces This ensures that as each subcomponent is developed separately when they are finally brought together they will be able to function together More information on bottom up development can be found in Lima and Oakes Service Learning Engineering in Your Community on page 63 Below are some examples of what types of considerations need to be taken into account during this step Mechanical How will different physical parts connect What types and where will fasteners be used What forces does each component need to be able to handle from other components Electrical How much voltage or current will be supplied received What type of signals will be sent digital analog Copyright 2008 EPICS 23 9 14 2008 EPICS Design Process How many inputs outputs Software How will each element or subroutine in the program communicate with the main program What format will the input output information be in How many inputs outputs 2 Design Analysis Evaluation of Project and Components The main task in this ph
24. drift Current Process Controls for Effect None Timer Outputting Incorrect time Time Corruption Data Bus error Daily observation Timer Outputting Incorrect time Time Corruption Chip Error Daily observation Timer outputting no time No time display Chip Error Daily observation Timer outputting no time No time display Bus Error Daily observation Timer Failing to idle Fatigue of laser Incorrect drifting setup Daily observation Timer Failing to idle No Reset Incorrect drifting setup Daily observation Timer Failing to idle Fatigue of sensor Incorrect drifting setup Daily observation Timer idle s too quickly Maze deactivates Incorrect drifting setup Daily observation Signal is overdriven Destroy attached part Part Fatigue Zeener fuse Signal is overdriven Run Time segment does Destroy attached part Goal light does not Power Input Spike Power Regulation Timer nofactivate ill mi ate Part Fatigue 1 Other Observation 6 18 correctly Timer Internal Data Inaccurate Time Cosmic Rays 1 None 8 24 Corruption Internal Data Reset to default Timer Corruption Logic Lock up Cosmic Rays 1 state possible 3 21 fuse blows inside laser maze will not voltage spike from power of power strip have power outlet 2 ungetectabie on PU regular power iain to a n
25. e but at a reduced level of performance Customers dissatisfied Moderate Minor disruption to production line A portion Less than 100 may have to be scrapped no sorting Item operable but some comfort corvenience item s inoperable Customers experience discomfort Minor disruption to production line 100 of product may have to be re worked Item operable but some comfort convenience item s operable at a reduced level _lof performance Customers experience some dissatisfaction Minor disruption to production line The product may have to be sorted and a portion less than 100 se worked Fit finish squeak rattle item does not conform Defect noticed by most customers Minor disruption ta production tine A portion less than 100 of the product may have to be re worked on line but out of station Fit fimish squeak rattle item does j not conform Defect noticed by average customers Very Minor Minor disruption to production line A portion less than 100 of the product may have to be re worked on line but in station Fit finish squeak rattle item does not conform Defect noticed by discriminating customers No effect Cause of Failure The following figure shows the rankings for the Cause of Failure category This category is ranked based on the likelihood of failure A ranking of one would indicate that the failure is almost improbable while a ranking of ten would suggest that the failure would occu
26. e including materials used and any changes made to the designs during the construction process Detailed description of any field testing done with the prototype including what tests were performed as well as what the results were and any feedback received Comparison of the prototype to the specifications Summary of major design decisions made in the design of the project Complete bill of materials for creation of the prototype Refer back to the explanation of how the factors listed below affected the Project Identification phase and explain how and why the factors affecting the specifications development phase are similar or different identifying the factors that are most important for this phase and how they relate to each other xii Aesthetic issues related to the physical appearance or appeal of the project both in terms of the external and internal design Copyright 2008 EPICS 31 9 14 2008 EPICS Design Process xiii Economic issues related to the cost of the project including the cost development production maintenance and in terms of both monetary and time costs xiv Environmental issues related to ecological effects as well as effects on the working environment of the users xv Ethical issues related to the professional responsibility intellectual property adherence to standards and codes etc xvi Health and Safety issues related to the risk of harm or injury to the user xvii Inclusiveness is
27. earched into already existing products that attempt to address the same or similar needs which you are attempting to address Now you will use the criteria you have just developed to analyze and compare those already existing products During this process you should be looking to see if you think any of these existing products will fulfill all of the needs of the customer as well as starting to gather information about what values you may assign to your criteria as you develop your specifications More information about finding benchmark products can be found in Lima and Oakes Service Learning Engineering in Your Community on page 60 4 Evaluation Criteria Once you have determined what exactly you will need your project to do and how someone will use it you will then need to find ways to evaluate different design Copyright 2008 EPICS 10 9 14 2008 EPICS Design Process options What you need to develop are a set of comprehensive measurable criteria that can be used during the evaluation process You should have criteria for each of the basic functions you ve developed Your criteria should also relate back to the user requirements the user analysis and the constraints You will also need to have specific criteria for the user interface These criteria should not have any specific values associated with them at this point these are simply a list of the measurable attributes of the design Categories of Evaluation Criteria Voland 20