A Minimum Phase Modeling Approach to Disturbance Observer Design for Balancing Control of a Single-wheel Robot

摘要

Stabilization of the inverse model of the target system is a critical problem in a current disturbance observer (DOB) based control scheme. When the system is identified as a second order system by the recursive least square (RLS) algorithm, the minimum phase (MP) of the model is not guaranteed. This paper addresses a guaranteed minimum phase method of the identified second order model. Jury's test is conducted to check the stability. All-Pass-Filtering (APF) process are conducted for updating prior parameters of RLS to satisfy the minimum phase criteria. To verify the proposal, a single-wheel robot is identified as a second order model by the RLS method with guaranteed stability. Disturbance observer is designed based on the model. Balancing control experiments of a single-wheel robot are conducted.