Chrysler's mileage accumulators use an electric absorber for road load simulation along with an independently controlled blower for vehicle cooling. The control system for the electric absorber is designed to permit programming of the various road load components in accordance with vehicle profiles specified by Chrysler engineers. The absorber portion is mounted below grade in a covered pit. The blower equipment is located at grade level directly in front of each vehicle. Reference signals are input to the absorber dc drive system which continuously calculates - via a small analog computing circuit - the summation of the component loads for instantaneous speed of operation. The dc drive then ″absorbs″ as much vehicle energy as necessary to produce the required load. In addition to this steady state loading capability, the mileage accumulators also feature electrical inertia simulation. All endurance testing at the facility is done by automatic driving systems. These consist of a tape reader, an analog controller, a servo motor-driven throttle actuator located in the vehicle and a pulse generator connected to the absorber roll. The test program is set up on a punch tape and fed into a tape reader. The controller then commands the actuator to open the vehicle throttle to reach the speed called for on the tape using the speed feedback device on the rolls to close this control loop. The tpae advances to the next step in the program as soon as the speed, time or distance objective for the current step has been attained.
机构:
NASA, Langley Research Cent,, Hampton, VA, USA, NASA, Langley Research Cent, Hampton, VA, USANASA, Langley Research Cent,, Hampton, VA, USA, NASA, Langley Research Cent, Hampton, VA, USA