Hybrid model predictive control of legless piezo capsubot

Abstract

In this paper, the hybrid modeling and predictive control of capsule robot (capsubot) systems are presented. First, the corresponding nonlinear state space equations are obtained from capsubot dynamics. Then, these state space equations are converted to a Piece-Wise Affine (PWA) system which is a class of hybrid systems. Next, this system is transformed to a Mixed Logical Dynamical (MLD) framework by defining binary variables representing the switching rules. At last, a Model Predictive Control (MPC) scheme is designed for this framework using a quadratic cost function resulting in a Mixed-Integer Quadratic Programming (MIQP). MPC approach excels other approaches due to its superiority in control of multivariable systems, unstable systems, non-minimum phase (NMP) systems, and systems with long delay. The main reason motivating us to use MPC for capsubot dynamics is its capability of handling constraints while reaching a desired performance. Simulation results illustrate the effectiveness of the proposed control approach.