多源激励下双层隔振浮筏系统的线谱混沌化

Line spectrum chaotification of a double-layer vibration isolation floating raft system under multi-source excitation

采用混沌化技术可以重构水下航行器的水声线谱特征,改善隐声性能.基于这一特殊应用背景,研究了多源激励下双层隔振浮筏系统的非线性时延反馈混沌化问题.在二维简化浮筏系统模型的基础上,完整地呈现了非线性时延反馈控制的线谱混沌化方法,为隔振浮筏的线谱混沌化设计提供了标准流程.仿真结果表明了该方法的可行性,探讨了多源激励条件下控制增益、时延和反馈频率等控制参数对系统混沌化效果的影响,并与单源激励进行了对比分析.

The line spectrum characteristics of the radiated waterborne noises of an underwater vehicle can be reconstructed using the technique of chaotification, which can improve the acoustic stealth of the underwater vehicle. According to the particular application background, in this paper we study the chaotification issue with nonlinear time-delay feedback control for a double-layer vibration isolation floating raft system under multi-source excitation. From a simplified two-dimensional floating raft system model, a chaotification method with nonlinear time-delay feedback control is presented completely. It provides a standard procedure for line spectrum chaotification design. Numerical simulation results show the feasibility of this method. Under multi-source excitation, the effects of the control gain, time-delay and feedback frequency parameters on chaotification are investigated, and discussion is also extended to the case of the single-source excitation.