Precision Decomposition Technique
for EMG Signals
Equipment

Figure 1: Schematic diagram of the quadrifilar needle and wire electrode and associated amplification scheme. We use three of the possible six differential combinations. The frame on the right presents typical motor unit action potential shapes from three channels. Note the distinctly different waveforms detected in the various channels.

Figure 2: Quadrifilar needle and preamp pod.

Figure 3: New Experimental Prototype of the EMG signal Decomposition System. The panel PC on the left presents information to the subject and accepts the input from the quadrifilar electrode and its associated amplification matrix. The laptop PC on the right displays the detected EMG signal and performs the signal decomposition.

Figure 4: A subject test-chair designed specifically to support the decomposition system and provide fixtures for recording the EMG signal and associated force output from tested muscles in the upper and lower limb.