Transitional command position modification for a controller

Abstract

A controller for a manipulator or robot having a plurality of power-driven, signal-controlled links interconnected to permit relative motion therebetween to define plural degrees of freedom. The links of the manipulator are controlled to perform movements corresponding to stored sequences of command positions. The controller stores, for each link, a sequence of command positions and is operable to add a further command position or a further sequence of command positions to the original sequence of command positions. In a non-synchronous mode of operation (where the movements of the robot are not sychronized with movement of the workpiece) or in a synchronous mode, a further command position is added to the end of the original sequence by producing a number of additional command positions and storing the additional command positions after the original sequence. The last of the additional command positions is substantially equal to the further command position. The position change per command of the additional commands is maintained generally constant. In like manner, in the nonsynchronous mode, the initial position of a further sequence of command positions can be added to the end of an original sequence. In a synchronous mode of operation a first and a second sequence of command positions can be connected. To do this, a portion of each original command sequence is replaced by a substitute sequence of command positions, preserving the correlation between the command position processing rate and the conveyor rate.