Multi-Resonant Controller for Frequency-Varying Disturbance Rejection in Stewart Platforms

Jonathan Culau; Rafael S. Castro; Guilherme A. Pimentel

doi:10.20906/sbai.v1i1.2735

Jonathan Culau Group of Automation and Control of Systems (GACS), Pontifical Catholic University of Rio Grande do Sul
Rafael S. Castro Group of Automation and Control of Systems (GACS), Pontifical Catholic University of Rio Grande do Sul
Guilherme A. Pimentel Systems, Estimation, Control and Optimization Group (SECO), University of Mons

DOI: https://doi.org/10.20906/sbai.v1i1.2735

Keywords: disturbance rejection, linear matrix inequalities, multi-resonant controller, quaternions, Stewart platform

Abstract

This paper presents the design of a robust disturbance rejection control scheme for Stewart platforms. To fully take into account the system nonlinearities, the quaternion based description is used along with Quasi-Linear Parameter Varying representation. In order to provide robust output regulation, in the presence of frequency-varying disturbances, we propose the design of a multi-resonant internal model controller. The closed-loop stability is guarantee by the state-feedback law synthesized via a convex optimization problem subject to linear matrix inequalities. Simulations show the effectiveness of the multi-resonant controller applied to a Stewart platform in the case that the platform is used as a stabilization device on the ocean where the ocean waves generate frequency-varying harmonic disturbances.