Comparison of Electromyography and Force as Interfaces for Prosthetic Control
By Corbett, Elaine A.; Perreault, Eric J.; Kuiken, Todd A.; Journal of Rehabilitation Research and Development, Vol. 48, No. 6, pp. 629-642Publication Date: 2011
Study compared electromyography (EMG) with force as interfaces to control a powered prosthetic arm. EMG is described as an indirect estimator of muscle force which may be expected to limit the control capabilities of the prosthesis user. Powered prostheses controlled directly by force use the proximal motion of the shoulder of the residual limb rather than any remaining distal musculature. Study participants were 5 men and 3 women aged 22 to 30 years who had no disabilities. A one-dimensional tracking task was presented to participants on a computer screen by means of a MATLAB graphical user interface. During the experiment, participants’ wrists were attached to an electrogoniometer placed on the computer worktable and supported by forearm padding. Electrodes were placed on wrist flexor and extensor muscles. Activation of forearm muscles provided the input for the EMG-controlled task. For the force-controlled task, forces were measured at the hand, and movement at the wrist was restricted. Results demonstrated that an EMG control interface is as effective as force control for the position-tracking task. Also examined were the effects of gain and tracking frequency on EMG control in order to explore the limits of this control interface. Information transition rates for myoelectric control were found to be best at higher tracking frequencies than at frequencies previously reported for position control.
Published by:
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/11/486/corbett486.html

