| 摘要 |
When the system is activated by switch 38, drive means 34, 36 and brake system 16, 18, 20 are controlled by speed control unit 22 to provide the level of acceleration or retardation demanded by accelerator pedal 30 or brake pedal 32, both of which are connected to the speed control unit 22. Each of a range of positions of the accelerator has an associated target speed, and the drive means or brake system are controlled to bring the vehicle speed towards the target speed at a rate which depends on the difference between the actual speed and the desired speed, with a greater difference being associated with a greater rate of change. The system may also control the transmission and may disconnect the engine from the vehicle wheels to enable the speed control to reduce the vehicle speed to zero while the engine is running. The target speed may vary with the drive ratio selected. The system may be used to control the descent of hills, particularly for off-road vehicles. |
