Two legged walking robot

I am looking into making a walking robot.
I don't have the money that they spent on osimo, so I plan on cheating by making my fast by injecting nitromethane into the cylinders. This will allow me to react to changes instead of having to predict them.

The cylinders use three pistons with holes in the outer casings acting as exhaust holes. A small servo attached to the arm being moved, slides the outer casing to open and close the vent holes.

Cylindar