摘要 |
An electronic control is provided for a vehicle having an engine, a main drive driven by the engine, a fluid pump driven by the engine for providing pressurized fluid, and a supplemental drive driven by the pressurized fluid. The electronic control includes a main drive sensor for sensing the speed of the main drive and responsively producing a main drive speed signal. A vehicle speed sensor senses the speed of the vehicle relative to the ground and produces a vehicle ground speed signal. A pressure sensor senses the pressure of the pressurized fluid supplied to the supplemental drive by the pump and responsively produces an actual pressure signal. A processor receives the main drive speed, vehicle ground speed, and actual pressure signals, produces a slip ratio signal responsive to a ratio of the main drive speed and vehicle ground speed signals, produces a desired pressure signal responsive to the slip ratio signal, produces an error signal responsive to a difference between the desired and actual pressure signals, and controls the fluid pressure in the supplemental drive in response to the error signal. |