Precision Decomposition Technique

for EMG Signals


Quadrifillar needle and wire electrode
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.

Quadrifilar Needle & Preamp Pod
Figure 2: Quadrifilar needle and preamp pod.

New Data Acquisition and Decomposition System
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.

Test Chair
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.