On a Proxy-Based Control as Multiple Controllers with Feedback Interconnections

A proxy-based control, in its core, is two controllers combined in series. This paper presents the fundamental aspects of such a unique control technique. We first establish the main features of a proxy-based control. These features are mainly related to the stability of a controlled system. Additionally, we propose a simple form of a proxy-based control and implement it into a test device for proof of concept. The simple proxy-based control that we propose in this paper is composed of two constant gains (proportional terms) and one integral term to remove the steady-state error. This integral term must be attached to the controller with the lower impedance. We also explore another feature of a proxy-based control during this hardware implementation: how we use one control gain to perform fine-tuning while using the other control gain to maintain system stability. We demonstrate this by adding an adaptation law also to the controller with the lower impedance. All obtained results align with the presented theory.