Abstract: An elevator system including an elevator car to be stopped at a predetermined stopping point from any initial speed below a predetermined maximum value, at a predetermined uniform rate of deceleration. The uniform rate of deceleration determines the desired speed versus distance-to-go reference pattern, which is initiated at a predetermined fixed distance from the stopping point. If the car speed is at the maximum value, deceleration will be initiated immediately. If the car speed is below the maximum value, the car is allowed to continue at the same speed until the car speed and location of the car relative to the stopping point match a point on the reference pattern. This point is accurately determined via digital feedback and comparison circuits which start the elevator car on the desired deceleration speed pattern with zero error.

Abstract: An elevator system which includes speed control apparatus which provides an error count representing the deviation of an elevator car from a desired speed versus distance reference pattern. Both the instantaneous and cumulative errors are indicated by the error count, and both are simultaneously corrected with digital precision by direct utilization of the error count. Anticipatory control of non-linear actuators responsive to the rate at which the cumulative error is corrected makes the system time optimal.