Interpretation of myoelectric power spectra: A model and its applications

Some essential elements of a mathematical model describing the power spectrum of myoelectric signals are presented. The influences of electrode cofiguration and of biological parameters such as muscle-fiber radius, action-potential conduction velocity, spread of synapses over the innervation zone, number of fibers per motor unit, and electrode-to-muscle distance are expressed in terms of filter functions modifying the shape of the power spectrum of the generator signal. Signal processing for parameter identification is described and results are listed. A few applications are discussed.