Stewart Katz, Paul Green, and Jill Fleming
This report describes an experiment to determine the measurement errors and typical data associated with driving an instrumented research vehicle (1991 Honda Accord Station wagon). The vehicle is outfitted with sensors for headway, lateral position, speed, steering wheel angle, and throttle position. Video equipment records what the driver does and the forward scene. Three sets of tests were conducted for each type of measurement: static, dynamic, and driver in the loop. For example, for headway, these measurements would correspond to the mean and standard deviation of the headway when the car is parked, when one vehicle follows another (both with cruise control set), and when a driver follows a lead vehicle (with only the cruise control of the lead vehicle set).
The standard deviation of the steering wheel angle was 0.8 ssu (steering signal unit) when held statically, 1.1 and 1.3 ssu when the vehicle was driven (and the wheel was held rigidly and loosely), and 1.5 ssu when the driver attempted to minimize lane variance. When the wheel was held rigidly to minimize lane variance, vehicle drift led to a lane variance of 0.5 ft. When the lane standard deviation was minimized by drivers, it was 0.2 ft. When the vehicle was static, the lane width has a standard deviation of 0.0 ft. With the cruise control operating, speed was sinusoidal (1.1 mi/hr amplitude, 15 sec cycle). Under driver control when conditions were optimal, the standard deviation of speed was 1.0 mi/hr.
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