Session T1H A Capstone Triumvirate of Courses to Satisfy ABET s Major Design Experience Requirements

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1 A Capstone Triumvirate of Courses to Satisfy ABET s Major Design Experience Requirements Juan C. Morales, PhD Chairperson, Department of Mechanical Engineering, University of Turabo, PO Box 3030 Gurabo, PR jcmorales@suagm.edu Abstract - A three-course approach is used to satisfy ABET s major design experience. The approach also satisfies ABET s program criteria. A course in Mechanical Systems Design and a course in Thermal Systems Design flank the Multidisciplinary Experience in Industry course. The Mechanical course addresses all the hard design skills through a one-semester project. The Industry course addresses the professional skills (communication, teamwork, ethics, etc.) in a real-world setting, in addition to increasingly more difficult problems that will require multiple semesters for completion of prototypes, testing and redesign. As one group of students graduates, a new group would take over the project. The Thermal course culminates the thermal stem and currently uses the multi-semester approach to design, build, and test lab equipment for use in the department. Examples are provided. Index Terms ABET, Capstone, Prototype INTRODUCTION The Mechanical Engineering program at the University of Turabo consists of 151 credits distributed into nine semesters (4.5 years). The curriculum culminates in three major design experiences, or capstone courses, as follows: a course in Mechanical Systems Design and a course in Thermal Systems Design flank a Multidisciplinary Experience in Industry course that provides exposure in local industry. A benefit of this approach is that the program criteria, which will be discussed shortly, is also satisfied since both the mechanical and the thermal stems of the curriculum are capped with a major design experience. The Industry course may address the mechanical stem or the thermal stem, or both, depending on the particular problem posed by industry. The set of three capstone courses, which gives rise to the name triumvirate [1], is shown schematically at the top of Figure 1, in relation to the mechanical and thermal stems of the curriculum. The curriculum also includes two engineering electives in addition to the required courses to satisfy the mathematics and science component, as well as the general education requirements of ABET. The Mechanical Engineering program at the University of Turabo was ABET accredited for the first time in the accreditation cycle. The capstone triumvirate approach documented in this paper was in place at the time of the ABET visit. University of Turabo - Mechanical Engineering Program CAPSTONE TRIUMVIRATE OF COURSES Mechanical Stem Thermal Stem MECHANICAL SYSTEMS DESIGN Mechanical Systems Lab (Design of Experiments) Machine Design Kinematics of Mechanisms Dynamics CAD (Introduction to Finite Elements: Cosmos - Solid Works) Materials Lab Strength of Materials Materials Statics Graphics (mostly Solid Works, some AutoCAD) MULTIDISCIPLINARY EXPERIENCE IN INDUSTRY FIGURE 1 THERMAL AND MECHANICAL STEMS LEAD TO THE CAPSTONE TRIUMVIRATE OF COURSES ABET REQUIREMENTS THERMAL SYSTEMS DESIGN Thermal Systems Lab (Design of Experiments) Heat Transfer Thermodynamics II Thermodynamics I Fluid Mechanics Lab Experimental Methods (Includes Labview) Fluid Mechanics For the 2004/2005 accreditation cycle, the major design experience was required as part of ABET Criterion 4: Professional Component. The relevant section of the criterion reads as follows [2]: Students must be prepared for engineering practice through the curriculum culminating in a major design experience based on the knowledge acquired in earlier course work and incorporating engineering standards and realistic constraints that include most T1H-19

2 of the following considerations: economic; environmental; sustainability; manufacturability; ethical; health and safety; social; and political. For the 2005/2006 and 2006/2007 accreditation cycles, ABET eliminated the last part of the sentence (constraint considerations) and included other minor changes. It reads as follows [3, 4] (the underlined words indicate the changes): Students must be prepared for engineering practice through the curriculum culminating in a major design experience based on the knowledge acquired in earlier course work and incorporating appropriate engineering standards and multiple realistic constraints. As can be deduced from the new wording, the essence of the major design experience did not change. Each program, however, now has the freedom to choose the particular realistic constraints that apply in their design projects. For the 2007/2008 cycle, ABET is proposing to maintain the same wording (page 22 of [4]). However, the major design experience requirements will be located in a new criterion, defined as Criterion 5: Curriculum. This change is due to a mandate by the ABET Board of Directors to restructure the four accreditation commissions so that the various criteria sections will occur in the same order. Nine, instead of eight, criteria will define the new document. The change in location does not in any way disturb the essence of the major design experience. In addition to the major design experience requirement, ABET also requires particular program criteria for each of the engineering disciplines. It is through the program criteria that ABET is able to take into consideration the different requirements for each discipline. The statement under the Program Criteria for Mechanical and Similarly Named Programs partially reads as follows [2, 3, and 4]: The program must demonstrate that graduates have: the ability to work professionally in both thermal and mechanical systems areas including the design and realization of such systems. This requirement of the program criteria has not changed since, at least, the accreditation cycle. However, ABET is proposing to locate the program criteria in Criterion 9, instead of in Criterion 8, for the 2007/2008 accreditation cycle. The change in location will not alter the essence of the statement. The fact that the program criteria requires that graduating students be able to work professionally in both the mechanical and thermal stems of the curriculum, was one of the principal reasons the Mechanical Engineering Program at the University of Turabo adopted the triumvirate approach. CLOSING-THE-LOOP ON CAPSTONE Initially, the major design experience in the Mechanical Engineering program at the University of Turabo consisted of a single, one-semester Capstone course in industry. Although the course successfully addressed the development of professional skills, and exposed students to a real-world setting, the evaluations performed during the semiannual closing-the-loop faculty meetings revealed unacceptable variability in the level of difficulty of the problems supplied by industry. More than one half of the projects did not address the knowledge acquired in earlier course work, nor did they address multiple realistic constraints. The need for an improvement strategy became evident. The capstone course analysis took place in one of the first semiannual closing-theloop meetings. These full-day departmental faculty meetings have become the most important driving force for the continuous-improvement process in the department. Further analysis of the capstone shortcoming uncovered three principal reasons for the variability in the level of difficulty of the capstone problems. 1. The first reason was the fact that there is an inherent variability in the problems that industry faces at any given point in time. On occasions there were several good projects, while at other times there were none. 2. The second reason was due to communication shortcomings between the students and the volunteer lead engineers from industry. The volunteer lead engineers were often very busy so their availability was limited. In addition, the students had to contend with the physical distance between the employers and the university. 3. The third reason was due to the one-semester limitation of the capstone course. Fifteen weeks is a short period of time to start and finish a major design experience in industry, while students are still registered in three or four additional courses at the university on a full-time basis. The 15-week limitation was creating a conservative mind set in the faculty members since, if they approved a problem with a high level of difficulty, the students would perhaps be unable to finish it in the allotted time. Or, if they were able to finish the project, it could be at the risk of sacrificing their performance in their remaining courses. At the same time, the results of the Exit Survey of Graduating Students showed that, although some students mentioned that their capstone problems were weak, the majority rated very highly the course itself, especially because of the exposure to industry. The results of the 2002/2003 Alumni Survey were similar. The course also includes many seminars regarding, among other, ethics, communication, (including resume writing and oral presentations), safety and project planning. Three oral presentations are required throughout the course and students get to polish these skills in front of a panel of engineers from industry. T1H-20

3 THE SOLUTION The solution to the capstone shortcoming had to take into consideration the fact that students enjoyed and valued the experience in industry. Therefore, the course itself could not be eliminated. However, the variability in the level of difficulty of the problems was intolerable. The expectation of the department was, and still is, that 100% of the graduating students should be exposed to a challenging design problem that fits the ABET major design experience requirements. The first step in the solution was to shift the focus of the major design experience away from the industry course, while still maintaining it in the curriculum. The course title was changed from Capstone Design Experience to Multidisciplinary Experience in Industry. The word design was taken out of the title in recognition of the fact that some problems would not be worthy of the design designation. The course structure, which excellently addressed the professional skills, including teamwork, communication and ethics, could remain exactly the same. The focus for the hard design skills expected of a major design experience would be shifted to a new course, Mechanical Systems Design, which did not rely on industry. The course would replace one of the four engineering electives in the curriculum. All the problems would be carefully selected by the faculty, who would then assure that all the hard design skills were addressed by the students. This solved the variability problem encountered with industry. All the projects would require a written report that included the following items: Problem definition Product specifications Alternative design ideas Selection of the best design idea based on a quantitative decision matrix Engineering analysis of the solution, using the knowledge gained in previous courses, to size the components. Cost analysis of the design Engineering drawings The use of engineering standards Consideration of the following realistic constraints: environmental; sustainability; manufacturability; ethical; health and safety; social; and political. The fact that industry was taken out of the loop, also solved the communication shortcomings the students had regarding the tight schedules of industry lead engineers, and the physical distance between the university and industry. The students only answered to the professor in charge of the course so the resolution time for questions became more agile. The one-semester time limit became feasible. The Mechanical Systems Design course became the anchor of the major design experience ABET requirement by virtue of thoroughly addressing the hard design skills. Furthermore, the fulfillment of the major design experience requirements became even more attractive when considered in combination with the professional skills developed in the Multidisciplinary Experience in Industry course. The final step in the solution was the need to fulfill the program criteria which requires that graduating students be capable of working professionally in both the mechanical and thermal areas. The Mechanical Systems Design course properly capped the mechanical stem but the thermal stem was still unresolved. The only way to achieve the required depth in the thermal stem of the curriculum was by taking an appropriate elective from the thermal area. This option, while feasible, left the curriculum somewhat exposed to mismanagement due to, among others, scheduling conflicts. The faculty decided to change the status of the Thermal Systems Design course from elective to required to assure that the thermal stem would be appropriately capped. The inclusion of this third course, Thermal Systems Design, gave rise to the Capstone Triumvirate name. Two engineering electives remained in the curriculum. EVOLUTION OF THE CAPSTONE TRIUMVIRATE The three courses ran in a one-semester mode for several semesters, including the semester in which ABET visited the program (September 2004). Each course started and finished a design project within a one-semester time frame. The idea of considering a move to a multi-semester mode started with the required laboratory course for mechanical engineering seniors. This course was modified after the ABET visit to concentrate on design of experiments. The students must design (and run) three experiments during the semester; two in the thermal stem and one in the mechanical stem. The objective of the first thermal design problem assigned to the students was to experimentally determine the thermal conductivity of an arbitrary piece of metal (the material type was unknown to the students). Although the students did a good design job, the results were off by a substantial margin. During the subsequent closing-the-loop meeting, the faculty examined the situation and the consensus reached was that the problem should be reassigned in the following semester to a new group of students. The new group of students would have to come up with a new and improved method to determine the thermal conductivity of the material. The second group successfully matched the expected value, as reported in the subsequent closing-the-loop meeting. The experience with the thermal conductivity experiment was the trigger for considering multi-semester experiences in the capstone triumvirate courses. The faculty realized that the one-semester time limitation could be defeated. We could start exploring more difficult and challenging problems. At the point where a group of students ended a design experience, a new group of students would pick up the problem in the following semester and extend it. The only exception would be the Mechanical Systems Design course which would safely anchor the triumvirate approach (in terms of ABET) by always assuring that students had a one-semester experience that fit the ABET requirements for a major design experience. T1H-21

4 By allowing multi-semester experiences in the Multidisciplinary Experience in Industry course and the Thermal Systems Design course, the program could start the process of designing a system, building a prototype, testing it, and redesigning it (to achieve all the specifications), without the typical constraints of a one-semester, or even a twosemester capstone experience. Students could start experiencing truly real-world engineering experiences within the university environment. EXAMPLE: THERMAL SYSTEMS DESIGN The first course to try the multi-semester approach was the Thermal Systems Design course. A piping network was designed and built by a group of students in the second semester of the 2004/2005 academic year. A second group took over the project in the first semester of academic year 2005/2006, to determine the performance of the system and to develop a Labview program to measure the data and calculate desired factors (pressure, flow rate, loss coefficients). Figure 2 shows the pipe network system as constructed by the first group. Figure 3 shows the front panel of the Labview program developed for the system. Figure 4 shows the block diagram of the Labview program that corresponds to the front panel shown in Figure 3. FIGURE 4 LABVIEW BLOCK DIAGRAM FOR FRONT PANEL OF FIGURE 3 EXAMPLE: MULTIDISCIPLINARY EXPERIENCE IN INDUSTRY The Multidisciplinary Experience in Industry course started the multi-semester approach in the second semester of the 2005/2006 academic year. During that semester a group of students designed a Fast Acting Roll-Up Door to target the pharmaceutical industry in Puerto Rico. The students used Solid Works software to draw the system and Working Model software to analyze its dynamic behavior. The door was partially built at the facilities of the industry partner. The next set of students (first semester of the 2006/2007 academic year) will continue fabricating the door and will test it. If time permits, a redesign of the door will be performed to refine the system; otherwise, this task may be assigned to a third group of students in the second semester of the 2006/2007 academic year. Figure 5 shows a perspective view of the roll-up door. Figure 6 shows a perspective view of the drive system. Figure 7 shows the control systems configuration. FIGURE 2 PIPE NETWORK SYSTEM FIGURE 3 LABVIEW FRONT PANEL FIGURE 5 FAST-ACTING ROLL-UP DOOR: PERSPECTIVE VIEW T1H-22

5 FIGURE 6 DRIVE SYSTEM FOR ROLL-UP DOOR: PERSPECTIVE VIEW FIGURE 8 VERTICAL LIFT RECLINER IN THE LIFT POSITIOIN FIGURE 7 CONTROL SYSTEM CONFIGURATION FOR ROLL-UP DOOR EXAMPLE: MECHANICAL SYSTEMS DESIGN The Mechanical Systems Design course serves as the safety anchor to assure that 100% of the students in the program are challenged with a major design experience that fits, within a one-semester time frame, most of the ABET major design experience requirements. Although manufacturability of the design is considered, the students are not required to fabricate the system. The example for this paper is taken from the work carried out in the first semester of the 2005/2006 academic year. The design is for a vertical lift recliner that targets elderly people. The system was drawn using Solid Works software. Figure 8 shows the system in the lift position while Figure 9 shows the system in the reclined position. FIGURE 9 VERTICAL LIFT RECLINER IN THE RECLINED POSITIOIN T1H-23

6 CONCLUSIONS This paper has documented the Capstone Triumvirate approach used at the University of Turabo Department of Mechanical Engineering. The triumvirate approach is safely anchored by the Mechanical Systems Design course which fits, within a one-semester time frame, most of ABET major design experience requirements. The remaining two courses, Thermal System Design and Multidisciplinary Experience in Industry, are evolving into courses that use a multi-semester approach. As a result, the faculty is beginning to explore more difficult and challenging problems. At the point where a group of students end a design experience, a new group of students pick up the problem in the following semester and extend it. Examples of student work from each course were presented. ACKNOWLEDGMENTS The author wishes to express his gratitude to the full-time faculty of the Department of Mechanical Engineering at the University of Turabo: Eduardo Castillo, Edwar Romero, Ferdinand Rosa, V. Sundararajan, Fernando Benítez, Diego Villegas, Mary Cristina Ruales, and Nilangely Arzón. The cohesiveness achieved within the group has permitted the closing-the-loop meetings to act as the driving force for the continuous improvement efforts of the department. The author hopes that this paper will serve as a motivating agent to the faculty to start writing, and sharing with the engineering education community, the details of the excellent educational improvements taking place in many of our courses. REFERENCES [1] Webster, Unabridged Dictionary of the English Language, 2001, RHR Press. [2] ABET, Criteria for Accrediting Engineering Programs, Baltimore, Md.: Engineering Accreditation Commission, p. 2. [3] ABET, Criteria for Accrediting Engineering Programs, Baltimore, Md.: Engineering Accreditation Commission, p. 3. [4] ABET, Criteria for Accrediting Engineering Programs, Baltimore, Md.: Engineering Accreditation Commission, p. 3, 22. T1H-24