A new outboard inductive damping valve without any electronic control system is developed. Its working principle,structure and external characteristic are studied. Its mathematical model is presented and its damping c...A new outboard inductive damping valve without any electronic control system is developed. Its working principle,structure and external characteristic are studied. Its mathematical model is presented and its damping characteristic is investigated on the basis of fluid continuity equation,differential equations of motion and Bernoulli equation. The influence of the valve parameters on the damping characteristic is studied numerically. The effects of outboard inductive damping valve and common damping valve on ride and tire load are compared also. The external characteristic of the valve is verified in bench test. The results show that the valve’s mathematical model is quite accurate and the developed valve can be adjust in two stages,which can also meet the requirements of the dynamic characteristic of the vehicle suspension system.展开更多
An improved localization method consisting of ＂filtering-time delay estimationhyperbolic localization＂ is proposed. Combining the empirical mode decomposition（EMD）and time delay estimation method based on generali...An improved localization method consisting of ＂filtering-time delay estimationhyperbolic localization＂ is proposed. Combining the empirical mode decomposition（EMD）and time delay estimation method based on generalized average magnitude difference function,the original signals are decomposed into intrinsic mode function（IMF） components. The energy distribution criterion and spectrum consistency criterion are used to select the IMFs, which can represent the physical characteristics of the source signal. Several sets of signals are applied to estimate the time delay, and then a vector matching criterion is proposed to select the correct time delay estimation. Considering the hydrophones location, a shell model is established and projected to a plane according to the quadrant before the hyperbolic localization. Results of mooring and sailing tests show that the proposed method improves the localization accuracy,and reduces the error caused by time delay estimation.展开更多
为了减小外部驱动IV型弯张换能器长度,提高此类换能器的实用性,提出在弯张壳长轴方向设计一U型凹槽、驱动单元置于凹槽内驱动的方案。利用有限元软件重点分析U型凹槽尺寸对换能器谐振频率和体积位移的作用规律,同时结合水中模型的发射...为了减小外部驱动IV型弯张换能器长度,提高此类换能器的实用性,提出在弯张壳长轴方向设计一U型凹槽、驱动单元置于凹槽内驱动的方案。利用有限元软件重点分析U型凹槽尺寸对换能器谐振频率和体积位移的作用规律,同时结合水中模型的发射电压响应,设计了一款谐振频率为2.2 k Hz、-3 d B带宽为330 Hz的嵌入式外部驱动IV型弯张换能器。这种结构的换能器不仅吸收了已有外部驱动IV型弯张换能器的优点,还弥补了其长度尺寸过大的缺陷。展开更多
基金Sponsored by the Major Program of the Chinese Academy of Sciences (QYY2008K012)
文摘A new outboard inductive damping valve without any electronic control system is developed. Its working principle,structure and external characteristic are studied. Its mathematical model is presented and its damping characteristic is investigated on the basis of fluid continuity equation,differential equations of motion and Bernoulli equation. The influence of the valve parameters on the damping characteristic is studied numerically. The effects of outboard inductive damping valve and common damping valve on ride and tire load are compared also. The external characteristic of the valve is verified in bench test. The results show that the valve’s mathematical model is quite accurate and the developed valve can be adjust in two stages,which can also meet the requirements of the dynamic characteristic of the vehicle suspension system.
基金supported by the National Natural Science Foundation of China(51209214)the Research Development Foundation of Naval University of Engineering(425517K031)
文摘An improved localization method consisting of ＂filtering-time delay estimationhyperbolic localization＂ is proposed. Combining the empirical mode decomposition（EMD）and time delay estimation method based on generalized average magnitude difference function,the original signals are decomposed into intrinsic mode function（IMF） components. The energy distribution criterion and spectrum consistency criterion are used to select the IMFs, which can represent the physical characteristics of the source signal. Several sets of signals are applied to estimate the time delay, and then a vector matching criterion is proposed to select the correct time delay estimation. Considering the hydrophones location, a shell model is established and projected to a plane according to the quadrant before the hyperbolic localization. Results of mooring and sailing tests show that the proposed method improves the localization accuracy,and reduces the error caused by time delay estimation.
文摘为了减小外部驱动IV型弯张换能器长度,提高此类换能器的实用性,提出在弯张壳长轴方向设计一U型凹槽、驱动单元置于凹槽内驱动的方案。利用有限元软件重点分析U型凹槽尺寸对换能器谐振频率和体积位移的作用规律,同时结合水中模型的发射电压响应,设计了一款谐振频率为2.2 k Hz、-3 d B带宽为330 Hz的嵌入式外部驱动IV型弯张换能器。这种结构的换能器不仅吸收了已有外部驱动IV型弯张换能器的优点,还弥补了其长度尺寸过大的缺陷。
