Virtual control strategy and conditioning technique for tracking and learning controls under input restrictions. (2022)

• Record Type: Journal Article
• Authors: Verrelli, C.M.
• Is Part Of: Annual reviews in control. Volume 53(2022)
• Page Start: 187
• Page End: 198
• Publication Date: 2022
• Subjects: Virtual control -- Conditioning technique -- Actuator faults -- Input saturation -- Tracking control -- Repetitive learning control; Automatic control -- Periodicals; Periodicals; 629.805
• DOI: 10.1016/j.arcontrol.2022.04.008
• Languages: English
• ISSNs: 1367-5788

Abstract

Abstract: The virtual control strategy for mechanical systems has been recently proposed (Gnucci and Marino, 2021) in the context of under-actuated mechanical systems. Such a strategy views and represents an under-actuated mechanical system as a fully actuated system with virtually added inputs and outputs having to satisfy, through a suitable choice of the virtual output reference signals, the virtual input zero-equality constraint: the related adaptive tracking control problem is then solved through standard design techniques. This paper exhibits a twofold aim. The first one is: to enlarge the concept of zero-input constraint and thus naturally adapt the virtual control approach to the case in which an actuator fault can occur. The second aim is: to show how the application and transposition of such an adaptation to two well-known classes of nonlinear systems (special systems in multi-variable tracking form with two inputs and outputs under actuator faults; one-relative-degree, single-input, single-output systems in output feedback form under input saturation) not only own strong connections with the conditioning technique, originally conceived in the context of anti-windup problems under input constraints, but they also gain original results.