The hydraulic motor is the rotary counterpart of the hydraulic cylinder as a linear actuator. The vibration is typically created by a motor or a piezoelectric actuator. The exhaust camshaft timing is still controlled using a hydraulic actuator. The selector drum actuator, transmission shafts and transmission shaft bearing were revised. Stems are either smooth for actuator controlled valves or threaded for manual valves. A familiar example of a manually operated hydraulic actuator is a hydraulic car jack. New features also include a revised selector drum actuator, transmission shafts, and transmission shaft bearing. It is basically a calibrated air damper with an automatic actuator. Postflight investigation traced the malfunction to a failure of the C-2 engine hydraulic gimbal actuator. There are many variations in the electromechanical linear actuator system. On 18 November "Endeavour" experienced a failure of a transducer on the elevon hydraulic actuator. The motor may be attached to the end of the actuator. Then it feeds the electromagnetic actuator, which amplifies the signal. This concept is based on using an EAP actuator configured in an array form. Smoke dampers are driven by a motor, referred to as an actuator.