Electromyographic evaluation of operator performance in manual control tracking

A study was conducted of ten subjects to evaluate electromyographic (EMG) correlates to learning during manual control tracking. Subjects were seated in front of a CRT screen and manually tracked two different trajectories on two different days. The surface EMG signal was gathered from the supinator longus muscle and RMS-averaged over one-half-second intervals. Comparison of EMG RMS energy for the two target trajectories suggested a velocity-tracking profile. A two-dimensional curve fit, using amplitude scaling and time lead-lag shifts, was obtained using the EMG data and the two trajectory velocities. Results suggest that goodness-of-fit coincides with tracking accuracy, with the better trackers having a lower mean squared error in the best fit.<>