Time-varying identification of the neuromuscular system. II. Isolated muscle mechanics

Studies of the mechanical properties of isolated whole-muscle and single fibers have used linear time-invariant system identification techniques. However, muscle is a dynamic, nonlinear, time-varying machine. Thus models describing the full range of muscle behavior must be both nonlinear and time-varying. The authors describe a mathematical approach as well as the associated experimental apparatus and technique for characterizing muscle models (and models of other biological materials) under time-varying conditions