Magnetic Suspension of Transhumeral Prostheses

Seamless human-robot interaction with biomechatronic systems requires reliable force transfer from an external device, through soft tissue, onto the human skeleton. In above-elbow prosthetic attachment, a significant clinical problem is residuum soft tissue damage from dynamic mechanical loads during daily activities like carrying loads and manipulating objects. To address this, we investigate magnetic force transduction from a prosthesis directly onto bone via a transhumeral ferromagnetic implant. For these upper-extremity prostheses, persistent magnetic attraction is required for secure attachment; our approach uses an architected and controllable permanent magnet array to overcome duty-cycle limitations of a conventional electromagnet. This interdisciplinary project focuses on three key areas: developing a controllable permanent magnet array for prosthetic arm suspension; designing a compact mechatronic actuator to drive the magnet array whilst minimally affecting the biomechanics of activities; and investigating robust control strategies for the magnet array that are effective across a range of everyday movements. Our aim is to create a more synergistic bionic system by reducing soft tissue stress and shear, ultimately advancing the field of biomechatronics and human-robot integration.

  • Project Lead: He Kai Lim
  • Surgical Collaborators: Dr. Nicholas Bernthal (Orthopaedic Surgery, UCLA)
  • Project Team: Will Flanagan, Richard Zhou

Relevant Publications

  • W. Flanagan, H. K. Lim, C. R. Taylor, T.R. Clites. “A Controllable Axial-flux Halbach Array.” IEEE Access (under review, preprint)