Underactuated Source Seeking by Surge Force Tuning: Theory and Boat Experiments

TL;DR

This paper develops and experimentally validates a source seeking control algorithm for underactuated boats, using surge force tuning and advanced stability analysis to operate without position or velocity measurements.

Contribution

It extends source seeking algorithms to force-actuated underactuated models, incorporating surge force tuning and stability analysis, validated through boat experiments.

Findings

Achieved semi-global practical uniform asymptotic stability.

Validated the approach with numerical simulations.

Demonstrated effectiveness through boat experiments.

Abstract

We extend source seeking algorithms, in the absence of position and velocity measurements, and with tuning of the surge input, from velocity-actuated (unicycle) kinematic models to force-actuated generic Euler-Lagrange dynamic underactuated models. In the design and analysis, we employ a symmetric product approximation, averaging, passivity, and partial-state stability theory. The proposed control law requires only real-time measurement of the source signal at the current position of the vehicle and ensures semi-global practical uniform asymptotic stability (SPUAS) with respect to the linear motion coordinates for the closed-loop system. The performance of our source seeker with surge force tuning is illustrated with both numerical simulations and experiments of an underactuated boat.