Ellipsoidal tube MPC of robots carrying glass plates

Abstract

This paper is about time-optimal robust model predictive control of a robot arm that carries a glass plate. We model constraints on the strains in the extremal fibers of the glass plate based on the section modulus and tensile strength to avoid breakages. In order to synthesize a control strategy, we propose to use a tailored ellipsoidal tube based model predictive control scheme, which can deal with these nonlinear strain constraints of the glass plate. The necessity of modeling the strains in the fibers as well as the properties of the proposed robust control method are illustrated in a realistic case study for a KUKA youBot model, which is simulated in the presence of process noise.