FREQUENCY BAND-LIMITED FRACTIONAL DIFFERENTIATOR IN PATH TRACKING DESIGN

A new approach to path tracking using fractional differentiation is proposed in this paper. It is an extension of a previous method considering a Davidson-Cole transfer function as I/O transfer function. A methodology for synthesized a prefilter is defined using I/O Frequency Band-Limited Fractional Differentiator (FBLFD) transfer function whose two main properties are having no overshoot on the plant output and by adding numerator to have maximum control value for short time. These properties are available whatever the values of its constitutive parameters. This permits synthesis from only three parameters. The optimum settling time of the I/O transfer function is thus obtained. Transfer function synthesis requires the maximum value of the control signal by taking into account a frequential constraint. The prefilter can be implanted in the same way as a classical digital filter.