Model-Free and Real-Time Unicycle-Based Source Seeking with Differential Wheeled Robotic Experiments

TL;DR

This paper introduces a simple, model-free extremum seeking control method for unicycle robots that effectively seeks sources in real-time, reducing oscillations and improving convergence in noisy environments.

Contribution

A novel, simple extremum seeking control design for unicycle robots that is model-free, real-time, and reduces oscillations while enhancing source-seeking performance.

Findings

Effective oscillation attenuation demonstrated in experiments

Improved convergence speed over existing methods

Robust performance in noisy, real-world conditions

Abstract

Many autonomous robots aimed at source-seeking are studied, and their controls designed, using unicycle modeling and formulation. This is true not only for model-based controllers, but also for model-free, real-time control methods such as extremum seeking control (ESC). In this paper, we propose a unicycle-based ESC design applicable to differential wheeled robots that: (1) is very simple design, based on one simple control-affine law, and without state integrators; (2) attenuates oscillations known to persist in ESC designs (i.e., fully stop at the source); and (3) operates in a model-free, real-time setting, tolerating environmental/sensor noise. We provide simulation and real-world robotic experimental results for fixed and moving light source seeking by a differential wheeled robot using our proposed design. Results indicate clear advantages of our proposed design when compared to the literature, including attenuation of undesired oscillations, improved convergence speed, and better handling of noise.