A computer-assisted medical system includes a manipulator arm and a controller. The controller includes a computer processor. The controller is configured to servo at least one joint associated with at least one manipulator arm segment of the manipulator arm, the servoing including executing a servo loop. Executing the servo loop includes obtaining an actual state of the manipulator arm, computing a difference between a commanded state and the actual state, where the commanded state is used for the servoing the at least one joint, and determining whether the difference exceeds an error threshold. Based on determining that the difference does exceed the error threshold, the commanded state is updated using an offset to reduce the difference, and. Based on determining that the difference does not exceed the error threshold, the commanded state is not updated. The controller is further configured to apply the commanded state to control the actual state.

A robot system including robot control devices, a network, and a mode changing device which switches between an automatic operation mode and teaching mode. In the state where the mode changing device selects the automatic operation mode, drive power is supplied to all of the robots regardless of the state of the enable device. In the state where the mode changing device selects the teaching mode, when the enable device does not permit operation of at least two robots, the drive power of all of the robots is cut.