Robust control synthesis to achieve a required loop shape-a generalized orthonormal basis function approach

In the paper a new control design method is developed to obtain a robust controller that realize the required loop shape. First, a transfer function, namely a fictitious controller, is identified between the model and the required loop transfer function. Then a robust controller is designed taking into consideration the approximation error of the designed loop transfer function. The designed controller achieves the loop transfer function and meets the robust stability and nominal performance requirements. In the paper the steps of the robust control synthesis are discussed, moreover a simulation example is shown to demonstrate the method in a numerical example