Efficient safe learning for controller tuning with experimental validation


Loading...

Date

2025-03-01

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

Optimization-based controller tuning is challenging because it requires formulating optimization problems explicitly as functions of controller parameters. Safe learning algorithms overcome the challenge by creating surrogate models from measured data. To ensure safety, such data-driven algorithms often rely on exhaustive grid search, which is computationally inefficient. In this paper, we propose a novel approach to safe learning by formulating a series of optimization problems instead of a grid search. We also develop a method for initializing the optimization problems to guarantee feasibility while using numerical solvers. The performance of the new method is first validated in a simulated precision motion system, demonstrating improved computational efficiency, and illustrating the role of exploiting numerical solvers to reach the desired precision. Experimental validation on an industrial-grade precision motion system confirms that the proposed algorithm achieves 30% better tracking at sub-micrometer precision as a state-of-the-art safe learning algorithm, improves the default auto-tuning solution, and reduces the computational cost seven times compared to learning algorithms based on exhaustive search.

Publication status

published

Editor

Book title

Volume

143

Pages / Article No.

109894

Publisher

Elsevier

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Active learning; Controller tuning; Bayesian optimization; Safe learning; Gaussian process regression

Organisational unit

03751 - Lygeros, John / Lygeros, John check_circle

Notes

Funding

180545 - NCCR Automation (phase I) (SNF)
787845 - Optimal control at large (EC)

Related publications and datasets

Is supplemented by: