Hybrid life-extending control of mechanical systems: experimental validation of the concept

The goal of life-extending control is to achieve high performance of complex dynamical systems (e.g., aircraft, spacecraft, and energy-conversion systems) without overstraining the mechanical structures and the potential bene"t is an increase in the service life of critical components with no signi"cant loss of performance. This paper presents a two-tier architecture and a design methodology of hybrid (i.e., combined discrete-event and continuously varying) life-extending control for structural durability and high performance of mechanical systems. A feedback controller at the lower tier is designed with due consideration to robust performance and damage mitigation. A variable-structure stochastic automaton is employed at the lower tier for status evaluation of structural damage while the overall system performance is maintained by the supervisory level discrete-event controller at the upper tier. Experimental results on a laboratory test apparatus are presented for validation of the proposed concept of hybrid life-extending control. ( 1999 Elsevier Science Ltd. All rights reserved.