Damage-mitigating control of mechanical structures: Experimental verification of the concept

The concept of damage-mitigating control is built upon the two disciplines of systems science and the mechanics of materials, and its goal is to achieve an optimized trade-off between the dynamic performance and structural durability of the plant under control. Simulation studies reported in recent publications show a substantial reduction of damage accumulation in the critical components of a rocket engine with no significant loss of performance. This paper reports an experimental verification of the damage-mitigating control concept on a laboratory testbed, which is a two-degree-of-freedom mechanical system excited by a computer-controlled shaker table. Test results demonstrate: (i) the important feature of optimized damage-mitigating control by extending the fatigue life up to 3 1/2 times with no significant performance degradation; and (ii) close agreement between the analytical prediction of damage and the experimental observations.