John Richardson designed the mechanical power loader exosuit, with input from Mead. Like the queen, a prototype was built out of wood and polythene bags stuffed with newspaper to see how the movement would work. The finished design was so cumbersome that stuntman John Lees, in a black skinsuit, operated it from behind. The battle between the queen and power loader was choreographed extensively, as Weaver risked serious injury battling a large, unwieldy animatronic. The camera was sometimes moved around to simulate subjects moving faster. The scene of the queen running at Ripley was one of the more difficult shots; the wires and rods had to be concealed, since they could not be removed in post-production. Miniatures were used for parts of the scene with go motion, a version of stop motion with motion blur added.