Course Info
ME 370: Mechanical Design I
This course focused on kinematics and dynamics of machinery, including analytical kinematics, force analysis, and cam design. Projects included linkage analysis and walker design.
Project Details
The objective of this project was to design a mechanical walker with the purpose of safely delivering snacks to college students living in dorms. The walker had to use a single motor to power both the legs and the snack mechanism, while maintaining a minimum walking speed of 0.1 m/s on tile or carpet. Additionally, the design needed to fit in the size of a shoebox, and the budget was limited to $200. Typically we would have physical constructed the walker mechanism, but because of the COVID-19 pandemic, we were limited to 3D CAD modeling.
Working in a group of 4 students, my responsibilities lied mainly in the CAD modeling and in the mechanical design analysis. We started out by brainstorming ideas for the walker, and decided to create a walker themed after the AT-AT four-legged combat walker from the Star Wars franchise. Altogether we designed a four-bar linkage system that could work as the legs using graphical linkage synthesis and position velocity acceleration (PVA) analysis. We then worked on a chassis and linkage structure CAD model, and then I did all the work with the actual mechanism, which included sizing and modeling spur gears, mounting shafts and other power transmission fixtures, and constraining and animating the mechanism in Creo Parametric. Our transmission used gears and round belt pulleys to accomplish the resulting motion. After the mechanism was developed, we also did more design analysis by reviewing the motion of the walker, and by performing dynamic force analysis to ensure that the joints were strong enough and the legs would not buckle.
This project taught me a lot about mechanical linkages, and the standard methods of designing, analyzing, and constructing them. Additionally, I enjoyed being able to work on CAD modeling and creating a more lifelike model using Creo Mechanism. This introduction to mechanism-oriented modeling also helped set the stage for me to constrain and animate our power transmission in Fusion 360 in the Design of a 2 Gear + Idle Transmission Project.