超磁致伸缩作动器的混沌非线性

Chaotic Nonlinearity of Giant Magnetostrictive Actuators

激励电流与输出位移之间的非线性影响超磁致伸缩作动器的性能,混沌现象是超磁致伸缩作动器非线性的重要方面。为研究超磁致伸缩作动器的混沌行为,建立了其非线性动态力学模型,用数值方法得到了反映系统非线性响应特性的分岔图、最大Lyapunov指数图、相图、Poincaré截面图、幅值谱等。分析结果表明,在低频条件下,激励电流过大或系统刚度过低都会导致混沌现象的出现。

Nonlinearity between exciting current and output displacement spoils magnetostrictive actuators＇ performance. Chaotic nonlinearity is an important aspect of nonlinear character for magnetostrictive actuators. To explore the erratic behaviors of the actuators, a nonlinear dynamic model was established. The bifurcation diagrams, Lyapunov exponent, phase portrait, Poincaré mapping diagrams, amplitude spectrum, etc., which demonstrate dynamical characteristics of the system were obtained by numerical integration. Analysis indicates that under the condition of low frequency range, chaos would appear when exciting current is high and stiffness of the system is relativelv low.