A present invention is a robot wrist actuator including a mechanical joint having a housing. First and second gimbal assemblies are rotatably mounted to the interior of the housing to provide pitch and yaw movement. A collar is rotatably attached to the housing. A drive mechanism is connected to the...http://www.google.es/patents/US4686866?utm_source=gb-gplus-sharePatente US4686866 - Compact robot wrist acuator
