System for powered ankle-foot prosthesis with active control of dorsiflexion-plantarflexion and inversion-eversion

A prosthesis comprising:

• a coupling configured to engage a residual limb of a subject;
• a shaft having a first end connected to the coupling and an opposing second end;
• a foot piece connected to the second end of the shaft, the foot piece comprising an ankle plate and a sole piece configured to contact a surface;
• at least one computer configured to detect a state of the foot piece and to transmit an indication of the state of the foot piece;
• and
• a motor assembly including a first motor, a second motor, a first drum, a second drum and a cable, the cable coupled to (i) a rear of the ankle plate, (ii) a front of the ankle plate, (iii) the first drum, and (iv) the second drum and running sequentially from (a) the rear of the ankle plate (b) to the first drum (c) to the front of the ankle plate (d) to the second drum (e) to the rear of the ankle plate, and wherein the motor assembly is configured to receive the indication of the state of the foot piece and to control a position of the ankle plate about a joint of the foot piece in at least two degrees of freedom based on the state of the foot piece using the first and second motors.