Dual-Mode Model Predictive Control of an Omnidirectional Wheeled Inverted Pendulum

This article describes the position and heading control of a novel form of omnidirectional wheeled inverted pendulum platform known as a collinear Mecanum drive. This concept uses four collinear Mecanum wheels to balance in a similar manner to a typical two-wheeled inverted pendulum while also being able to simultaneously translate directly along its balance axis. Control is performed using a constrained time-optimal infinite horizon model predictive controller, with feasibility maintained across the full reference input set. Explored in this article is the derivation of the system dynamics model and controller, a systematic approach to selection of controller parameters and analysis of their effect on control performance and complexity, and an evaluation of the controllers efficacy in both simulation and on a real-world experimental prototype for simple and complex trajectories.