Determining Acceptable Range of Surface Electromyogram Electrode Placement Variation for Deltoid Muscle Using Euclidean Distance Function

摘要

Right electrode placement is very crucial in studying surface Electromyogram (sEMG) signal from any human muscle. The guidelines for electrodes placement as well as skin preparation has been specified by Surface Electromyography for the Noninvasive Assessment of Muscles (SENIAM) project that can be used by sEMG researcher to perform suitable sEMG electrode placement in their experiment setup. According to previous researchers the best position to place electrodes for specified muscle is at the muscle belly. However there is no special instrument to measure or identify the exact location of the muscle belly. The uncertainty of exact location for electrodes placement could be a problem if a signal is expected to be recorded and studied from the same muscle for certain period of time or days where electrodes need to be attach and reattach, since it would record different sEMG values even though subject perform similar muscle contraction. Thus to overcome this problem we set up a range of location where sEMG electrodes could be placed to get right EMG recording from the same muscle. We tested on deltoid lateral muscle, and as result sEMG data that were recorded by the electrodes that we placed 1cm apart from its initial position will still be at least 90% similar to reference data. The comparison between tested sEMG data and reference sEMG deltoid data were accomplished by using Euclidean Distance function.