Using the conformal compensator superfields of N=2 D=4 supergravity, the Type IIB S-duality transformations are expressed as a linear rotation which mixes the compensator and matter superfields. The classical superspace action for D=4 compactifications of Type IIB supergravity is manifestly invariant under this transformation. Furthermore, the introduction of conformal compensators allows a Fra...

The polynomial matrix equation X\Dr + Y\Nr = Dk is solved for those X\ and Y\ that give proper transfer functions X^~Y\ characterizing a subclass of compensators, contained in the class whose arbitrary element can be cascaded to a plant with the given strictly proper transfer function NrDr l such that wrapping the negative unity feedback round the cascade gives a system whose poles are specifie...

A method of designing a family of robust compensators for a single-input/single-output linear system is presented. Each compensator’s transfer function is found by using a genetic-algorithm search for numerator and denominator coefficients. The search minimizes the probabilities of unsatisfactory stability and performance subject to real parameter variations of the plant. As the search progress...

Traditionally in servo systems, the PI(D) controller has been widely used, while other types such as the PDF controller has been applied in some applications. In this article, the PDFF controller which has feedforward term in addition to a conventional PDF(Pseudo-Derivative Feedback) controller is introduced. Tracking and regulation characteristics of the PDFF controller in motion control appli...

Given a linear plant and a linear model, the partial model matching consists of designing a stabilizing compensator so as to match several first Markov parameters of the model. Using a recently established solvability condition, all such compensators are parametrized. The degrees of freedom can then be used to optimize the system performance. 0 1997 Elsevier Science Ltd.