title: Resolving the limb position effect in myoelectric pattern recognition.
abstract: Reported studies on pattern recognition of electromyograms (EMG) for the control of prosthetic devices traditionally focus on classification accuracy of signals recorded in a laboratory. The difference between the constrained nature in which such data are often collected and the unpredictable nature of prosthetic use is an example of the semantic gap between research findings and a viable clinical implementation. In this paper, we demonstrate that the variations in limb position associated with normal use can have a substantial impact on the robustness of EMG pattern recognition, as illustrated by an increase in average classification error from 3.8% to 18%. We propose to solve this problem by: 1) collecting EMG data and training the classifier in multiple limb positions and by 2) measuring the limb position with accelerometers. Applying these two methods to data from ten normally limbed subjects, we reduce the average classification error from 18% to 5.7% and 5.0%, respectively. Our study shows how sensor fusion (using EMG and accelerometers) may be an efficient method to mitigate the effect of limb position and improve classification accuracy.
authors.affiliation: Department of Engineering Cybernetics, Norwegian University of Science and Technology, Trondheim, Norway. anders.fougner@itk.ntnu.no
authors.forename: Anders
authors.initials: A
authors.lastname: Fougner
authors.forename: Erik
authors.initials: E
authors.lastname: Scheme
authors.forename: Adrian D C
authors.initials: AD
authors.lastname: Chan
authors.forename: Kevin
authors.initials: K
authors.lastname: Englehart
authors.forename: Oyvind
authors.initials: O
authors.lastname: Stavdahl
mesh_terms: D000293:Adolescent; D000328:Adult; D001185:Artificial Intelligence; D001186:Artificial Limbs; D003627:Data Interpretation, Statistical; D004558:Electric Stimulation; D004576:Electromyography / Q000145:classification / Q000379:methods*; D005121:Extremities / Q000033:anatomy & histology / Q000502:physiology*; D005260:Female; D006225:Hand / Q000502:physiology; D006801:Humans; D008297:Male; D009038:Motion; D009119:Muscle Contraction / Q000502:physiology; D010363:Pattern Recognition, Automated / Q000379:methods*; D011474:Prosthesis Design; D055815:Young Adult