A vehicle dynamics design and simulation tool for Capstone projects

Abstract

A vehicle dynamics simulation tool developed by students and for use by student design teams is presented in this work. The project is the result of work done by students participating in an exchange program between international partner universities. Students in the exchange program complete a Senior Capstone Design project and additionally write a Diploma Thesis as part of earning degrees from both universities. The simulation tool is meant for use in the early stages of the design of four-wheeled vehicle projects such as the SAE Mini-Baja challenge or the SAE Formula competition. The simulation tool uses MATLAB and Simulink and simulates a14- degrees-of-freedom (DOF) system. The model can accommodate different suspension linkages and allows anti-roll bars in the simulation and includes is capable of simulating Ackermann, parallel steering and reverse Ackermann steering. Non-linear tire modeling simulates turning forces from different types of tires on various surfaces. Results of low speed cornering simulation are verified by a physical test with a passenger vehicle at low velocities. The results of the high velocity cornering analysis are cross-referenced with findings in vehicle dynamics literature. Simulations provide turning radius estimation and the determination of the under-steer and over-steer behavior of the vehicle. Suspension impact forces and suspension travel in cases of impact from a user specified height are included. The design and simulation tool is opensource allowing future teams access to the software for future updates or revisions. A tutorial is included that provides teams with instructions on the software usage, facilitating the decisionmaking process earlier in the capstone design schedule than would otherwise be possible. © 2011 American Society for Engineering Education.