Patent ID: 6913327

Claim:
A method to operate an actuator, comprising: determining a force exerted by the actuator on an external device, determining a command force to the actuator, and monitoring a position of the actuator and determining a pseudo-force extended by the actuator on the external device; operating the actuator in a force-control mode when the determined force exerted by the actuator on the external device exceeds a first threshold; operating the actuator in a position-control mode when the determined force exerted by the actuator on the external device is less than a second threshold and the command force to the actuator is less than a third threshold; operating the actuator in the force-control mode when the command force exceeds a fourth threshold: and operating the actuator in the force-control mode when the command force exceeds a fifth threshold and an absolute value of a difference between the command force and the pseudo-force is less than a sixth threshold.