Closed-loop feedback control of motor speed of surgical stapling and cutting instrument based on system state

摘要

A motorized surgical instrument is disclosed. The surgical instrument includes a displacement member, an energy source, a motor, control circuitry, and a position sensor. A control circuit is to initiate firing of the displacement member with a predetermined electrical load on the energy source, the predetermined electrical load being applied to the motor to activate the displacement member and to initiate the position sensor. Monitoring the position of the displacement member via, continuously sampling the voltage of the energy source during the first interval of movement of the displacement member, comparing the sampled voltage with a threshold voltage, sampling Continuing to fire a displacement at a first rate when the sampled voltage is greater than or equal to a threshold voltage, or adjusting the first rate when the sampled voltage is less than the threshold voltage; Is configured to do. Techniques for handling motor stalls and transitioning between speeds are also disclosed.