Masaaki Yamaoka

Mode switching control for a personal mobility robot based on initial value compensation

The present paper introduces a novel standing-up control strategy using Initial Value Compensation (IVC) for a Personal Mobility Robot (PMR). Personal mobility robots, which are wheeled inverted pendulum type mobility-assist devices, have the advantages of a small turn radius, maintaining a level seating posture on a slope, and a small footprint as compared to conventional electric wheelchairs with four wheels. On the other hand, the user must maintain the posture of the PMR by the use of additional assist wheels on the ground when mounting/dismounting and working from the PMR. In order to achieve these requirements, we propose the following approach. First, the PMR accelerates to lift its assist wheels off the ground and detects whether the assist wheels are in contact with the ground. The feedback controller is then switched to wheeled inverted pendulum mode using the proposed IVC. The proposed IVC is designed to improve the transient responses and suppress the amplitude of the control input and the jerk component for reducing the shock to the driver. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype PMR.

A Feedback/Feedforward Accommodation of Load Change and its Application to Control of Reformer for Fuel Cell Vehicle

Abstract Output regulation for nonlinear plants with large load variation is considered assuming that a nonlinear model of the plant for simulation is available. A linear model of the plant for a fixed load is obtained via 4SID method which naturally leads to a feedback/feedforward control architecture. The control configuration is applied to control of reformer for fuel cell vehicle, where H∞ control is applied for feedback. It is shown both theoretically and experimentary that the overall feedback/feedforward configuration achieves a high performance of regulation under heavy load change.