Design and control of a two-wheeled robotic walker for balance enhancement

Abstract

This paper presents the preliminary design results and control strategy of a two-wheeled inverted pendulum (TWIP) robotic walker for assisting mobility-impaired users with balance and stability. A conceptual model of the vehicle is developed and used to illustrate the purpose of this study. Motor dynamics is considered and the linearized equations of motion for the system are derived using Newtonian mechanics. In order to eliminate the effects of loop interaction and impose the desired dynamics on the system, a decoupling control scheme was implemented. Upright stabilization of the robotic walker is achieved using linear quadratic regulator (LQR) control. Improved disturbance rejection is achieved through the implementation of a pitch controller. Simulation results demonstrate that a robustly tuned pitch controller can mitigate effect of disturbance on the linear displacement of the vehicle by as much as 74%.

Controlador LQR y SMC Aplicado a Plataformas Pendulares

“…Las diferentes tcnicas desarrolladas en los ltimos aos para el control de estructuras pendulares, ha permitido una mayor eficiencia en sus realizaciones, trayendo consigo, un incremento en su uso comercial [4]; es as como es posible observar en la industria diversas aplicaciones en sectores como: aeroespacial, biomecnica o transporte; con usos como el control activo para despegue de cohetes [15], la estabilidad de prototipos bpedos caminantes [16] o el mencionado medio de transporte Segway [17].…”