An initial sketch of the instrument.
Two bicycles are connected to each other via a gear box. On one bike sits the mannequin with a bicycle wheel for a head. On the other bike sits the musician. As the musician pedals, the gears turn, causing the mannequin to pedal. The gear box is hooked up to a semi-dismantled reel-to-reel player. The pedalling of the musician makes the reels spin and the tape move past the tape head. Hence, the musician is able to control the playback action of the reel to reel player through the pedals.

 

Sketches of the gear box setup