CLOSED LOOP FEEDBACK CONTROL OF MOTOR VELOCITY OF A SURGICAL STAPLING AND CUTTING INSTRUMENT BASED ON MAGNITUDE OF VELOCITY ERROR MEASUREMENTS

摘要

A motorized surgical instrument is disclosed. The surgical instrument includes a displacement member. A motor is coupled to the displacement member and a control circuit. A position sensor is coupled to the control circuit and a timer circuit to measure elapsed time. The control circuit is configured to determine a position of the displacement member, determine an error between directed and actual velocity and adjust the directed velocity based on the error in comparison to one or more thresholds. The control circuit also is configured to adjust the rate of change of the directed velocity based on the one or more thresholds. The control circuit also is configured to determine a zone in which the displacement member is located and set the directed velocity based on the zone in which the displacement member is located.