Novel postural control algorithm for control of multifunctional myoelectric prosthetic hands.
The myoelectric controller (MEC) remains a technological bottleneck in the development of multifunctional prosthetic hands. Current MECs require physiologically inappropriate commands to indicate intent and lack effectiveness in a clinical setting. Postural control schemes use surface electromyography signals to drive a cursor in a continuous two-dimensional domain that is then transformed into a hand posture. Here, we present a novel algorithm for a postural controller and test the efficacy of the system during two experiments with 11 total subjects. In the first experiment, we found that performance increased when a velocity cursor-control technique versus a position cursor-control technique was used. Also, performance did not change when using 3, 4, or 12 surface electrodes. In the second experiment, subjects commanded a six degree-of-freedom virtual hand into seven functional postures without training, with completion rates of 82 +/- 4%, movement times of 3.5 +/- 0.2 s, and path efficiencies of 45 +/- 3%. Subjects retained the ability to use the postural controller at a high level across days after a single 1 hr training session. Our results substantiate the novel algorithm for a postural controller as a robust and advantageous design for a MEC of multifunction prosthetic hands.
Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO;
Jacob L
JL
Segil
Richard F
RF
Weir
D000465:Algorithms; D001186:Artificial Limbs; D004576:Electromyography; D006225:Hand; D006801:Humans; D009048:Motor Skills / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D011474:Prosthesis Design; D014584:User-Computer Interface
EMG; biomechatronics; electromyography; hand; limb prosthesis; multifunctional prosthetic hand; myoelectric control; postural control; transradial prosthesis; upper-limb prosthesis