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This paper describes the design and implementation of the SEA, Ltd. Brake and Throttle Robot (BTR). Presented are the criteria used in the initial design and the development and testing of the BTR, as well as some test results achieved with the device. The BTR is designed for use in automobiles and light trucks. It is based on a servomotor driven ballscrew, which in turn operates either the brake or accelerator. It is easily portable from one vehicle to another and compact enough to fit even smaller vehicles. The BTR is light enough so as to have minimal effect on the measurement of vehicle parameters. The BTR is designed for use as a stand-alone unit or as part of a larger control system such as the Automated Test Driver (ATD) yet allows for the use of a test driver for safety, as well as test selection, initiation, and monitoring. Installation in a vehicle will be described, as well as electronic components that support the BTR.

Vehicle testing often requires accurate speed control, whether maintaining a constant speed or following a dynamic speed profile. A portable brake and throttle robot designed for this task must quickly and automatically adapt its control to each test vehicle's mass and powertrain characteristics in order for the controller to perform well on a wide variety of platforms. This application presents two major challenges. First, each new vehicle installation requires rapid retuning of the controller. Manual tuning can be very time-consuming. Second, the “plant” is very nonlinear and asymmetric. Different actuators are employed for acceleration (engine) and braking (road loads and friction brakes). After a broad survey of control strategies and their suitability for this particular application, neurofuzzy techniques were among the most promising.