Design decisions and performance analysis in the Shigley Hauler project,a competitive machine design project

Abstract

Practical hands-on experience in mechanical engineering education has proven to be advantageous in many studies. The Shigley Hauler project in the mechanical engineering undergraduate program at the University of California, Davis has been running for more than 23 years and asks students to design, fabricate and test an electro-mechanical system to lift a heavy load up a ramp. Students are given a small DC electric motor and a set of plastic gears and have to design, fabricate and test their system under given constraints. This paper reviews the different design approaches for subtasks and how they have evolved over the years. The availability of different manufacturing processes at the student machine shop has impacted the design and fabrication in recent years, such as additive manufacturing, waterjet cutting, and laser cutting. Lastly, internet ordering also changed the material acquisition with the improved accessibility of low-cost components and raw material, but also more risk with variable lead times and component quality, which is explored with the example of the motor sourcing. The relationship between the Shigley Hauler design and the competition results show certain best practices, but also the flexibility of the project for unusual ideas.