UK Centre for Materials Education
Working with you to enhance the student experience
Working with you to enhance the student experience
Dr I. D. Jenkinson, School of Engineering, Liverpool John Moores University
The aim of the project was to develop a web based learning resource of case studies in which a range of simple components were reverse engineered. The components were selected to illustrate the application of a range of materials (particularly polymers) and manufacturing processes. Each case study was to be based on a component selected from products of relevance to a first year undergraduate.
The ability to solve design problems depends not only on analytical competence but also on the ability to approach the problem in a way that gives consideration to the available resources, manufacturing techniques, costs, market place etc [1]. The overall purpose of the project was to help students develop a systematic approach to the design process including the important aspects of materials application and manufacturing processes.
Figure 1 Front page
The project has resulted in the production of case studies based on products used in areas of sport and leisure activities. Figure 1 shows the front page and the chosen products. The components selected were simple to model using CAD and illustrated the application of a range of materials and processing methods. For example the clip from a rucksack and the footrest from a trials bike Figure 2 and 3, demonstrate the application of polymers and plastic injection moulding, and of sheet steel and press working and welding.
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Figure 2 Clip from a rucksack |
Figure 3 Footrest from a trials bike |
In each case study the function, form and manufacture of the component is described using CAD solid models, computer simulations and video clips. The function of the component and important design criteria are presented, an example is given Figure 4. In addition to looking at the operating and loading conditions, the student is presented with target component costs and production quantities.
The key features of the design are identified followed by a simple analysis of the component’s design. Since the component is developed as a CAD solid model a range of computer simulations using FEA etc. are readily available to illustrate the analysis of the design.
Information on the materials used is presented together with the process of materials and process selection.
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Figure 4 Component function and criteria |
Figure 5 Evaluation of key design features |
The manufacturing processes are illustrated using the CAD models and simulations. The footrest was used to illustrate sheet metal work and welding processes. The sheet metal model was developed from the solid model and the actual process was illustrated using video clips.
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Figure 6a Component manufacture |
Figure 6b Component manufacture
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In the case of clip, the plastic injection process is presented using simulations developed from the CAD model. The flow of polymer through the die is animated and temperature and pressure gradients and sink mark locations can be visualised. Students receive guidance on the principles of mould design and are made aware of potential problems that could encourage defects and quality issues in the product. The simulations also provide an indication of quality of the mould: its expected mechanical properties and appearance.
Figure 7
The component tooling was also manufactured so that students would have the opportunity to experience and experiment with the actual process during a later laboratory session. Manufacture of the tooling in-house also enabled the developers to reproduce each stages of its manufacture from the creation of the EMD electrodes to the final die sinking process.
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Figure 8 |
Figure 9 |
The resource was used to support a first year module in computer-aided design and manufacture, which required students to undertake a case study of their own along similar lines. It also provided a framework around which to tackle open-ended design problems set in other modules.
An initial evaluation of the resource using first year undergraduates has proved promising. However, the number of case studies developed is limited and significant analysis was not possible. When questioned many students stated that they had found that the combination of web based information and simulations, supported by the practical work in the process laboratory useful. The aim of the developers is therefore to continue to add further examples in order to cover a wider range of materials and processes.
1. S.D.Sheppard, ‘Design as Cornerstone and Capstone’,
Mechanical Engineering Design, ASME, Nov 1999
2. K.L.Wood, D. Jensen, J. Bezdek, K. Otto, ‘Reverse Engineering
and Redesign: Courses to Incrementally and Systematically Teach Design’,
Journal of Engineering Education, July 2001
3. J.N. Fawcett and J.F.L. Chan - 'Product Investigation for first-year
Mechanical Engineering students', International Journal of Mechanical
Engineering Education, Volume 26 Number 3, 1998
