Engineering Design ProcessDr. Gbekeloluwa B. OguntimeinCEGR 106

Learning ObjectivesStudents will be able to :Describe the different steps in the design process.Explain the importance of economics in design processExplain the importance of team in the design processApply project management techniques.

Learning Objectives (contd)Explain how constraints, regulations, standards, safety factors, design life, and risk affect design process.

IntroductionEngineers use scientific principles and laws to identify and solve problems.The physical and chemical principles are applied in designing products and in providing services.Engineers continue to research ways of improving the efficiency of products and services designed.Engineers are empowered in technical experience to develop new and improved product and systems. But engineers must be aware of the impact of their actions on the society and the environment.

Introduction (contd)Engineering design is a systematic process by which solutions to needs of humankind are obtained.According to the accreditation board for Engineering and Technology (ABET), Engineering design is the process of devising a system, component, a process to meet desired needs.It is a decision making process (often iterative) in which the basic sciences, mathematics, and engineering science are applied to convert resources optimally to meet a stated objective.The design process is the same irrespective of the engineering discipline.Engineers consider cost, efficiency, reliability, and safety in their designs.

The Design Process (Moaveni,2008)1ProblemIdentification8Presentation7Optimization6Evaluation5Synthesis4Conceptualization3Research&Preparation2ProblemDefinition&Understanding

The Design Process (Eide et al., 1998)9Specification

8Decision7Analysis6Alternativesolutions5Criteria 10Communications4Constraints1Identify the need2Define2DefineProblemOr Need3Search

The Design Process (Dhillion,1996)1ProblemIdentification12Consumption11ProductDistribution10Production9Solution Presentation8Experimentation7Analysis6Conceptualization5Idea Generation4Specification

3InformationGathering2ProblemDefinition

The design processThere are many description of the number of steps in the design process 8, 10, & 12 depending on the product or servicesThe first step is recognizing the need for the product or services. This might be a request from a client, government for improvement in an existing product or services. Customers might want a better product.

The design Process (contd)Citizens in the community general determines the need for product and services.A need reflects dissatisfaction with an existing condition of product or services.

The design Process (contd)The second step is defining and understanding the problem or need completely. This is the most crucial and important step in the process. It requires the utmost care. Questions are asked to determine what the problem is so that an adequate solution would be arrived at.Good problems solvers are those who first fully understand what the problem is.Wrong definition could lead to solving the wrong problem.

The design Process (contd)The third step is doing preliminary research and preparation.Gathering useful information necessary to solve the problem. The search for information may reveal facts about the situation that result in redefinition of the problem.Literature search is very important so as not to repeat what has failed in the past or reinventing the wheel.A considerable amount of time is spent at this step.

The Design Process (contd)Sources of information include:Internet search is now available for most subjects areas.Library (Public, university & company), computer databasesGovernment documentProfessional organization

The Design Process (contd)Once information are gathered they are reviewed and organized in a suitable manner.The source of the information would form the bibliography or reference section in your report.

The Design Process (contd)Up to this point the problem definition is as broad as possible for maximum number of potential solutions.However , there are physical and practical limitations called constraints that will reduce the number of solutions for any problem.

The design Process (contd)Task Specification or Design Criteria help the design engineer achieve the design objectives.These are important parameters and data controlling the design and directing it towards the stated goal. Typical design criteria are:CostReliabilityWeightEase of operationCompatibilitySafety featuresNoise levelEffectivenessDurabilityFeasibilityAcceptance

The Design Process (contd)Conceptualization of ideas for possible solutions.During this phase ideas or concepts that could offer reasonable solutions to the problem are generated.Alternative solutions are considered taking advantage of the many techniques developed specifically for the purpose.During this stage creative and innovative activity that produces a number of possible alternative solutions to the desired goal occurs.The result of conceptualization may take the form of sketches or free-hand drawings.

The Design Process (contd)Methods used in arriving at alternative solutions areCheck off lists are generated by asking questions like:How existing solutions can be modified or rearrange to produce a better solution?Morphological listing gives visual conception of possible combinations that might be generated.These listings are usually shown as grids or diagrams.

The Design Process (contd)Brainstorming among team members.Free expression is important and encouragedThe project manager takes the leadAll members of the team have equal participation.

The Design Process (contd)Synthesis/ Analysis of the findingsDuring this stage details of the design are considered.The proposed alternative solutions are examined against physical laws, design specifications/criteria to identify optimum solution(s).Analysis involves the use of mathematical and engineering principles. Calculations, computer modeling are used in narrowing down the type of material to be used, the components of the system to determine the performance of a solution.

The Design Process (contd)Evaluation of ideas in details.Calculations are further performedExperiments may be performed.Physical models, Prototypes, Mock-up are built and tested.The best solution must be identified.Details of how the product is to be fabricated must be worked out fully.

The Design Process (contd)Optimization to arrive at the best solution.There are two types of design:A functional designAn optimized designFunctional design meets all of the pre-established design requirements but allows for improvement to be made in certain areas.

The Design Process (contd)Design optimization is always based on some particular criterion such as:CostStrengthSizeWeightReliabilityperformance

Optimization ProcedureInitialDesignPerformanalysis EvaluateResultsOf analysisCan the Design be improvedFinaldesignModifydesign

The Design Process (contd)Presentation of solutionAn oral presentation (Power point) to client, boss.Detailed technical written report to document the design.

The Design Process (contd)This is a combination of the progress report which is given on a regularly basis during the design period.The final report will contain graphs, charts, engineering drawings with an executive summary.Communication skills are important good people skill required in the engineering profession

The Design Process (contd)Design team is a group of individuals with complimentary expertise such as problem solving skills, working together as a team to solve a problem to achieve a common goal.The soul of the project is the Team.A good team is one that gets the best out of each otherCommunications is an essential part of a successful teamwork.

The Design Process (contd)The use of project management techniques enhances the success of the design process. Project Manager leads the teamHe is a facilitatorHe is a generalistHe uses a system approach.Project managementProject PlanningProject scheduling, Work Breakdown Structure (WBS), TasksConflict resolutionEngineering Economics : economic factors play important roles in engineering design decision making