A medical device having a force transmission mechanism that includes a chassis having a pivotal support that defines a first axis. An axle is supported by the pivotal support and is free to rotate around the first axis of rotation. The axle defines a second axis of rotation perpendicular to the first axis of rotation. A first control arm is coupled to a first end of the axle and is free to rotate around the second axis of rotation. A second control arm is coupled to an opposite second end of the axle and is free to rotate around the second axis of rotation independently of the first control arm. A distal component is coupled to an elongate tube that is coupled to the chassis. Four drive elements coupled to the control arms control motion of the distal component. In one implementation, the medical device is a teleoperated surgical instrument.
