Chaos control of a shape memory alloy structure using thermal constrained actuation

Shape memory alloys (SMAs) have been widely used in smart structures due to their adaptive properties. Their thermomechanical coupling can provide vibration attenuation or actuation providing a desired dynamical response. Chaos control methods can provide the stabilisation of unstable periodic orbits allowing one to choose a convenient response. Besides, it can promote bifurcation control that can avoid undesirable responses. This work investigates the chaos control of smart structures employing time-delayed feedback control to perform orbit stabilisation. A two-bar truss is of concern using thermal actuation of SMA elements. Thermal constraints defined by energy equation are investigated, showing the real possibilities of this kind of control. Numerical results show situations related to controller constraints, defining its range of applicability. Control strategy potentialities are discussed showing unstable periodic orbit stabilisation, exchangeable target control and bifurcation control.