A self-actuating robot or vehicle tether capable of moving itself, remaining free while traversing around obstacles, and free itself is disclosed. In a preferred embodiment of the invention, a valve is mounted to the tether or robot. An inflow conduit attached to or in the tether is connected to the valve. A fluid flows through the tether and the valve is opened and closed to create a waterhammer effect in the inflow conduit. The forces created on the tether from the waterhammer effect result in motion of the tether and in freeing of the tether from obstructions. Closing and opening the valve further creates pressure changes in the tether, thereby causing momentary dimensional changes in the tether. In an alternative embodiment, a plurality of valves are placed along the tether. Pulsing of the plurality of valves while a fluid flows through the tether results in the tether effectively moving itself.