Design, Build And Test: An Approach For A Capstone Design Course In Engineering Technology

Undergraduate engineering technology students traditionally take a capstone or senior design course during their last semester which involves the design of an engineering system that has a real application. Senior design projects usually focus on specific design aspects including equipment sizing, cost analysis, and material selection; however, many senior design courses do not give students the opportunity to apply hands-on skills or produce a real physical prototype. Furthermore, few engineering technology courses provide the opportunity to approach practical design and production problems in a comprehensive and holistic manner. There is a real need to expose students to a variety of design considerations as well as production, construction, or testing activities so that they may grasp fully the importance of the design process. Students also should learn to take into consideration constraints such as time, cost, and space during the design process. In this paper, a case study is presented in which a group of senior design students was able to design, build, and test a passive cooling system for residential, commercial, and industrial flat roofs. First, the students created a number of designs for a passive cooling system taking into consideration material properties, cost, manufacturability, and proven passive cooling concepts. The students then evaluated each of the design options and fabricated only those with the best overall design attributes. All prototypes were tested using a lab-scale experimental set up capable of measuring the thermal performance of each specimen. The students also provided a thorough discussion on the benefits and drawbacks of each prototype, and recommended a course of action for the potential commercialization of the proposed technology. The case study illustrates that students can learn to design, build and test a simple system taking into account several objectives and attributes in a comprehensive manner. This particular experience indicates that future capstone design courses should regularly consider prototype construction and testing as essential components of the entire design process. Introduction and Motivation Senior design courses offer students the opportunity to manage a multidisciplinary capstone project in a relatively short period of time; however, few colleges and universities have student projects that involve design, construction, and testing of multi-component systems 1-2 in the same course. In some universities, the senior-design course is preceded by a structured course sequence 3-4 to guarantee a certain level of expertise before students take their final design course. Others 1,5 have design-build-test senior capstone projects that take an entire academic year to complete. The design, construction, and testing of a mechanical system requires a good understanding of basic principles to be able to meet the established design criteria; however, senior design projects should also give the students the opportunity to see first hand the different phases of product development in a short period of time (i.e. one semester). In addition, engineering and engineering technology students should be able to: P ge 13375.2 • Design and build mechanical systems within a limited budget • Integrate and use multiple engineering and science disciplines in a simple and organized manner • Understand the importance of design and see first hand the impact of each design decision • Select materials and components taking into account physical properties, cost, durability, and manufacturing constraints • Use and manage time effectively • Consider manufacturing and fabrication issues during the design process • Take into account testing and validation concerns of each designed prototype • Assess each designed prototype by taking into account performance, cost, durability, ease of installation and operation It is shown in this paper how a simple project gave a group of students the opportunity to design, build, and test a passive cooling system by taking into account all the considerations highlighted above. This particular experience indicates that capstone design courses should regularly consider a design-build-test approach to enhance the students’ understanding about the importance of a well-organized design process.