shifting his body weight and turning his torso Is "the hybrid human-machine" the subject of the verbs "shifting" and "turning", or is it saying that Stelarc himself shifts and turns his body to activate such motions?? Context: Stelarc has been working with the Performance Art Digital Research Unit at Nottingham Trent University and the School of Cognitive and Computing Sciences at the University of Sussex to create Hexapod, a hybrid human-machine powered by a combination of electrical and pneumatic systems, which looks like a large wired-up metal insect, in the midst of which he will stand, shifting his body weight and turning his torso to activate a dog-like walking motion.