Automatic selection of different motion profile parameters based on

Abstract

An elevator system (FIG. 1) employing a microprocessor-based group controller (FIG. 2) communicating with elevator cars (3,4, . . . ) to affect the assignment of cars to hall calls at a plurality of floors in the building, using different, speedier car motion profiles and system motion parameters when the average waiting time is increasing beyond an acceptable delta (.DELTA.) [e.g. .+-.15% or .+-.5 sec.] or exceeds a specific pre-set limit (e.g. thirty-five seconds), indicating high traffic intensity (FIG. 3). This causes each of the assigned car(s) going to the relevant floor(s) to be given a higher jerk rate and acceleration & deceleration rates for reduced waiting time and improved service time. When relatively high intensity traffic conditions are no longer present, the relevant cars are changed back to a profile with a lower jerk rate and acceleration & deceleration rates for enhanced passenger comfort. To measure the average waiting time, the number and the time entered of all hall calls placed is collected, along with the floors involved in the calls, during an interval, and the average waiting time for the calls computed. In the first approach the computed average waiting time is compared to the previous computed average waiting time and, if it equals or exceeds an unacceptable delta (.DELTA.) or difference, the profile is increased. In the other approach, if the computed average waiting time exceeds the pre-set limit, the profile is increased. The highest available profile is also preferably used whenever the car is empty.