Parameter estimation of system dynamics with modulation-type noise?‚??application to the modelling of the dynamic relationship between the EMG and force transients in muscle

In most of the well known procedures for parameter estimation of system dynamics, it is assumed that disturbances acting on the system are additive and independent of the input to the system. In mathematical modelling of biological systems, this assumption is often unreasonable; in addition, to accomodate the variety of phenomena present in biological systems, developments of existing parameter estimation techniques are required. Of the existing methods of system parameter estimation, those based on the `instrumental variables¿ principle are among the simplest and most useful in practical applications. An algorithm based on this principle is developed for the parameter estimation of linear systems with modulation-type noise. The application of the technique is illustrated in the modelling of the dynamic relationship between the electrical and mechanical activity of muscle.