Testing a Formula SAE Racecar on a Seven-Poster Vehicle Dynamics Simulator

Abstract

Vehicle dynamics simulation is one of the newest and most valuable technologies being applied in the racing world today. Professional designers and race teams are investing heavily to test and improve the dynamics of their suspension systems through this new technology. This paper discusses the testing of one of Clemson University’s most recent Formula SAE racecars on a seven-poster vehicle dynamics simulator; commonly known as a “shaker rig.” Testing of the current dampers using a shock dynamometer was conducted prior to testing and results are included for further support of conclusions. The body of the paper is a discussion of the setup and testing procedures involved with the dynamic simulator. The results obtained from the dynamic simulator tests are then analyzed in conjunction with the shock dynamometer results. Conclusions are formed from test results and methods for future improvements to be applied in Formula SAE racing are suggested. INTRODUCTION Formula SAE is an international competition where colleges and universities from around the world test their design skills and mechanical abilities as they compete against each other in Detroit, MI with racecars they have designed and fabricated. Clemson University has been exceedingly successful in all its competitions finishing in the top ten in each of these, including Rookie of the Year in 1998 with a finish of 6, which was repeated the following year. A well-developed suspension system is very important to be successful in the Formula SAE competition. Clemson therefore decided to test their dampers on a shock dynamometer in order to determine the quality of the current dampers while also placing their recent racecar on a seven-poster shaker rig. This would corroborate the qualitative data received through driver feedback and lap times during testing with quantitative data from the simulation, while also confirming previous assumptions for suspension setup. Figure 1. Clemson Formula SAE racecar setup on the seven-poster dynamic simulator. EQUIPMENT The seven-poster shaker rig can be used to test a broad range of vehicles from Formula One to NASCAR and even a Formula SAE racecar. The shaker rig simulates track surfaces and disturbances at each tire contact patch along with three downforce inputs simulating aerodynamic forces and inertial g-forces through hydraulic actuators. The rig is operated on a seismic mass to isolate the instrumentation from outside vibrations and provide more accurate results. It is powered by a hydraulic pump and a 100-hp, water-cooled electric motor, all of which are housed in a separate room [2].