Using a scale testbed: Controller design and evaluation

To circumvent the cost and inherent danger in testing aggressive vehicle controllers using full-sized vehicles, a scale vehicle testbed has been developed for use as an evaluation tool to bridge the design gap between simulation studies and full-sized hardware. We describe vehicle dynamic models of the IRS simulation system, along with experimental verification using frequency response and parameter measurements. The next section provides a detailed discussion of dynamic similitude via the Buckingham pi theorem (1914), as well as a graphical comparison between distributions of dynamic scale parameters of scaled and full-sized vehicles. Following that, a yaw rate vehicle controller is introduced to exemplify the type of investigations that can be conducted with the IRS. The controller uses differential torque and brake inputs to assist the driver to control the yaw rate of the vehicle and is designed to achieve model tracking while allowing the driver to maintain control over the front wheels of the vehicle.