Contractivity-based variable gain dynamic motion control for a laser beam steering system: Synthesis and performance analysis

• Published in: Control engineering practice Vol. 135; p. 105517
• Main Authors: Reyes-Báez, Rodolfo, González-Romeo, Lorenzo L., Guerrero-Castellanos, J. Fermi, Jayawardhana, Bayu
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2023
• Subjects: Backstepping; Contraction analysis; Optomechatronics; Servo-systems; Variable gain; Backstepping; Variable gain; Optomechatronics; Contraction analysis; Servo-systems
• ISSN: 0967-0661; 1873-6939
• DOI: 10.1016/j.conengprac.2023.105517

This paper deals with the synthesis and experimental performance evaluation of a contractivity-based nonlinear dynamic motion control scheme for a Laser-Beam Steering (LBS) system, which includes a saturated integral action and a variable gain. The variable gain, in the control law, is used to discriminate between “signal” and “noise” in the velocity measurements, allowing to do a trade-off between the low-frequency tracking and disturbance rejection properties and high-frequency measurement noise amplification, an effect known as waterbed effect. Then, the contractivity-based framework handles the stabilization problem together with the closed-loop performance, allowing one to generalize key properties of linear control systems to analyze transient and steady-state solutions performances in the nonlinear case. The proposed control scheme is evaluated on an experimental platform for the set-point regulation and trajectory tracking problems under different scenarios. Moreover, the effectiveness of the proposed control scheme is compared with linear controllers for the LBS system available in the literature. •Robust nonlinear dynamic controller for a laser-beam stabilizing servo-system.•The controller ensures that the closed-loop system is contractive.•The control includes a saturated integral action and a variable gain of the velocity.•The strategy handles the trade-off between disturbances and measurement noise.•Real-time experiments are carried out to validate the theoretical development.