A very useful update would be gears, based on size of the circular brush. In conjunction with this, there could be a hydraulic element which forces liquids through closed circuits. This could be used in applications to build pressure and released in an instant. The hydraulic element could also be activated by electric. The size of the Hydraulic element could also be taken into effect too. And input?
honestly, it would be like a grow, shrink, grow, shrink based on how long/large it is. pscn could turn it on, could turn it off. or it would just be conductible.
Incredibots2 could do it using its 2D engine, I believe all that would need to be done is apply a code to the engine to allow such a thing as movable solids, rockets would become fathomable and anything else that moves.