Physical model-based active vibration control using a dielectric elastomer actuator

Abstract

Dielectric elastomer is a new type of electroactive material, which has the potential to provide effective actuation for a wide range of applications. The force, strain and speed of response properties of dielectric elastomer material place it somewhere between those of piezoceramics and shape memory alloys. In this study, the use of a dielectric elastomer tubular actuator for adaptive vibration isolation, where an electromechanical model of the actuator is utilised as a part of the feedforward controller estimation scheme, is examined. Active vibration isolation, with time-varying loads, is considered using a feedforward adaptive control approach. In this approach, a black-box cancellation path model is generally used to ensure convergence of the filtered-x least mean squares estimated controller parameters. Here the feasibility of using a cancellation path model comprising of the physical-based electromechanical model of the combined dielectric elastomer actuator and its ‘sensitive’ load is investigated. The implementation presented involves auto-tuning a finite impulse response filter representation of the physical-based cancellation path model whenever a loading change in the system is detected. When the finite impulse response filter representation has been updated, the adaptive feedforward control automatically turns back on. Load sensing is required to supply a value of the time-varying load to the model.