Robust frequency shaping sliding mode control

Frequency shaping, linked with linear quadratic optimal and sliding mode control, is a technique for controlling systems with uncertainties. The authors propose some new methods for designing the sliding surface and sliding mode control when the LQ weighting functions are not constant at all frequencies. Furthermore, they introduce conditions for which the spectrum of the original reduced system is a subset of the spectrum of the augmented system, and develop an iterative optimal construction procedure for the sliding mode.