DEVELOPMENT OF SELF-SENSING MAGNETORHEOLOGICAL DAMPERS FOR STRUCTURAL VIBRATION CONTROL

Abstract

Magnetorheological (MR) dampers have been successfully used in vibration control of civil and mechanical structures. Application examples include vibration control of stay cables in cable-stayed bridges, vibration damping of automotive seats and suspension systems, and vibration isolation of automation and precision equipmenthachines. While usefulness, the existing MR dampers are incapable of self-sensing structural vibration for implementing real-time, closed-loop vibration control. This paper describes the development of a kind of novel MR dampers possessing the attractive sensing-while-damping function with a high degree of sensor-damper collocation. Lead zirconate titanate (PZT) piezoceramic sensors and PZTipolymer piezocomposite sensors have been embedded, respectively, with actuation-only MR dampers to form two self-sensing MR dampers. The sensors have specifically designed geometry and electrode pattern to provide an optimal sensibility. Performance tests have been conducted by mounting the self-sensing MR dampers on a material test system operating in various displacement-controlled excitations, including sinusoidal and ramp excitations with different combinations of frequency and amplitude. Good agreements between the sensor outputs and the force inputs have been observed. The damper embedded with piezocomposite sensor has shown a higher sensitivity and a better reliability than the one integrated with piezoceramic sensor. The self-sensing MR dampers have great potential to be used in real-time close-loop vibration control of civil and mechanical structures.