Edwin Odom

Shop orientation to enhance design for manufacturing in capstone projects

The traditional undergraduate engineering curriculum provides methods of analyzing and creating paper designs, but does much less in teaching design for manufacture and production. The Capstone experience at the University of Idaho uses a mentor-based design process that takes projects from the conceptual stage through creation of functional prototypes. Graduate student mentors in the Idaho Engineering Works (IEWorks) have created a three-session orientation that teaches fundamentals of machining associated with the construction of a small multi-tool. Student feedback recorded in their design journals underscores the benefits of this shop orientation in promoting machine design skills that result in high quality prototypes delivered to industry customers at the end of the course and in fostering a close relationship between mentors and students.

Accurate and precise fabrication of iosipescu shear test specimens

The experimental measurement of the shear modulus and shear strength has been of special interest to the materials and composites community for a number years. In recent years, the Iosipescu shear test method has become popular and widely used. The most widely used test fixture is the Modified Wyoming test fixture which requires a specific and accurately fabricated specimen. To date, the methodology to fabricate and inspect these specimens has been left to the discretion of the individual investigators. This technical note presents a suggested methodology for the accurate and precise fabrication of Iosipescu shear test specimens. Dimensional data and the associated error from specimens fabricated are presented as verification of the methodology.

An Experimentally-Based Analytical Model of the Stress Field in an Iosipescu Composite Test Specimen

Typically, the reduction of the load and strain data obtained during an Iosipescu shear test assumes constant shear strain and shear stress distributions. While this is nominally correct and simplifies the data reduction, it provides no insight into the shear stress-shear strain distribution and can lead to theoretically inconsistent experimental results. In this study, an Idaho Iosipescu test fixture, two sizes of strain gages, an assumed power law for the strain distribution, and the Richard-Blacklock stress-strain relationship have been combined to model both the shear strain and the shear stress profile across the gage section. The results show a strain distribution dependent on both load and laminate layup and the difference between the shear stress and the shear strain profile. The initial shear moduli found from the nonlinear model show an insignificant difference between the two layups which is in agreement with composite theory.

Development of the University of Idaho Parallel Hybrid FutureTruck

The Advanced Vehicle Concepts Team (AVCT) at the University of Idaho (Ul) modified a 2002 Ford Explorer to meet the objectives of the 2002 FutureTruck competition. The challenge was to improve fuel economy, decrease emissions, perform work safely, provide a high quality education, increase public awareness, and project a positive image. AVCT used a business-oriented, multi-disciplinary approach to address the general objectives. For the performance objectives, the team used a combination of simulations, experiments, and modeling. The resulting configuration is a low voltage, mild parallel hybrid incorporating a 4.0-liter, V6 Ford engine and a direct current, electric motor. The first prototype resulted in a 22% increase in fuel economy and a substantial reduction in greenhouse gas emissions except for hydrocarbons. An engine sensor malfunction was the suspected cause of increased hydrocarbon emissions.

A sophomore capstone solid modeling experience: Virtual dissection and reassembly of legacy drawings

A sophomore computer aided design course is investigated with respect to its ability to prepare students for an authentic team-based design experience surrounding solid modeling of a set of legacy drawings by a master draftsman from an earlier age. Work products include an electronic archive stored on a shared drive, part and subassembly renderings, a shop-ready drawing package, accurate animation of part assembly as well as normal operation, and reflective writing about the project. Preparation for the final project includes justin-time use of locally authored videos supplied via the course website, deployment of peer mentors within the computer lab, and scaffolding provided by four different mini-projects. Intermediate milestones given on the course website, impromptu instructor/team/mentor meetings next to computer monitors as well as an overhead projector screen, and exemplary portfolios of student work are considered essential for guiding team-based work on the final project. Significant personal growth in engineering graphics skills leading up to the final project and throughout the final project has been observed in an end-of-course surveys that explore many attributes of pre-cad sketching, part modeling, assembly modeling, and creation of engineering drawing packages. Some refinements to the survey are needed to capture more of the wisdom embedded in many legacy drawings and the wisdom typically gained through the final project.

RATIONALE AND METHODOLOGY FOR DEPLOYING AXIOMATIC DESIGN IN INTERDISCIPLINARY CAPSTONE DESIGN COURSES

Capstone design courses require balanced attention to structured design processes as well as development of high quality design solutions. Process elements are commonly built into these courses through intermediate deliverables such as progress reports, design reviews, design reports, and forums for displaying prototypes as well as hardware. Despite this formal structure, steady evolution of design quality is not assured. Personal interaction with instructors, mentors, and clients is needed to evaluate intermediate designs and focus team efforts on design deficiencies as well as on promising design features. Clarification of functional requirements, determination of optimal design parameters, and implementation of viable solutions often requires considerable instructor and design team iteration. Design intent behind instructor feedback given at these junctures is not immediately obvious to many students. This paper outlines the rationale behind selecting and the methodology for deploying axiomatic design as a primary tool in an interdisciplinary design course. The selection of axiomatic design was based on 1) limited bandwidth for the introduction of new tools, 2) the desire to facilitate communication about design attributes between students and instructors, and 3) to provide continuity of application between various phases of the design process.