Adaptive control and parameter-dependent anti-windup compensation for inertia-varying quadcopters

• Published in: International journal of control Vol. 97; no. 2; pp. 235 - 248
• Main Authors: Farber, B. E., Richards, C. M.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 01-02-2024; Taylor & Francis Ltd
• Subjects: Adaptive control; anti-windup compensation; Antiwindup compensators; Control systems design; Controllers; Deviation; Helicopters; Inertia; Linear matrix inequalities; linear parameter-varying systems; Mathematical models; Model reference adaptive control; Parameter identification; Performance enhancement; quadcopters
• ISSN: 0020-7179; 1366-5820
• DOI: 10.1080/00207179.2022.2138555

A novel parameter-dependent anti-windup compensator is developed to improve the performance of a constrained model reference adaptive controller. The combined control structure solves the input saturation and stability problem for inertia-varying quadcopters. The control synthesis follows the conventional two-step anti-windup design paradigm where a nominal controller is designed without consideration of input saturation while the anti-windup compensator is designed to minimise deviations from nominal performance caused by saturated inputs. To account for the varying inertia of the quadcopter during package retrieval/delivery routines, inertia parameters of the vehicle/package are estimated with an online recursive identification technique. These estimates are used by the model reference adaptive controller and to schedule the parameter-dependent anti-windup compensator. Anti-windup performance and stability conditions are formulated as a set of parameter-dependent linear matrix inequalities, which when solved, yield a gain-scheduled anti-windup compensator that ensures stability and minimises deviation from nominal performance when saturation occurs. The effectiveness of the combined control scheme is demonstrated by simulations of an input-constrained quadcopter lifting a payload of unknown mass.