In ships having two rudders, an angle error exists if there is a difference in structural and electrical parameters in two steering gear systems. Such an error also results in reduced efficiency of ship maneuverabilit...In ships having two rudders, an angle error exists if there is a difference in structural and electrical parameters in two steering gear systems. Such an error also results in reduced efficiency of ship maneuverability during navigation. For the sake of reducing the angle error, a synchro-ballistic control approach based on cloud model is proposed in this paper. First, the mechanism model of steering gear system is introduced. Second, the structure of synchro-control system of twin-rudder is proposed based on the master-slave control strategy. Third, synchro-ballistic controller based on cloud model is designed to solve the nonlinearity and uncertainty of system. Finally, the designed controller is tested via simulation under two different situations. The simulated results demonstrate that this method is simple and has stronger robustness against the variation of states and parameters of plants. Hence, the validity and reliability of the method is proved for synchro-control of two rudders, which is a significant engineering application.展开更多
To counter the strong disturbance caused by the rotation of steering axle, a synchro-compensation methodis proposed to absorb the generated disturbance now by driving the loading motor stator to make it synchronously ...To counter the strong disturbance caused by the rotation of steering axle, a synchro-compensation methodis proposed to absorb the generated disturbance now by driving the loading motor stator to make it synchronously rotatewith its axle. Through analyzing and discussing different kinds of synchro-compensation schemes, the determinedpassive position and speed synchro-compensation systems are designed and simulated by computer. The results prove thatthisa method is effective to eliminate the strong disturbance of the steering axle.展开更多
Applying the air impact molding method to mold the complicated pattern with wider opening surface and deeper concave, there always exist vaulted phenomenon and lower compactibility of sand mold over the entrance and t...Applying the air impact molding method to mold the complicated pattern with wider opening surface and deeper concave, there always exist vaulted phenomenon and lower compactibility of sand mold over the entrance and the concave regions. Using the air-stream and synchro-formed clamp plate impact molding, however, this problem will be preferably solved. In this paper, the compact mechanism of the new molding method and the effect of some configuration factors, such as the area flowed by compressed air and the highness of the protruding block displacement around the diffluent clamp plate, on the compactibility of sand mold were discussed.展开更多
液压设备在运行过程中伴随着多域间的能量转换,尤其在变工况下呈现出非平稳性及非线性等特征,为状态监测与故障诊断带来难度。为了提高非平稳工况轴向柱塞泵故障诊断的性能,该研究提出采用既是运行参数又是状态参量的瞬时转速信号作为...液压设备在运行过程中伴随着多域间的能量转换,尤其在变工况下呈现出非平稳性及非线性等特征,为状态监测与故障诊断带来难度。为了提高非平稳工况轴向柱塞泵故障诊断的性能,该研究提出采用既是运行参数又是状态参量的瞬时转速信号作为轴向柱塞泵故障诊断的信息源。通过理论分析得出瞬时转速信号的波动成分中蕴含着元件健康状态信息。提出采用同步提取标准S变换(synchro-extracting of normal S transform,SNST)对其进行线通滤波处理。利用K-medoids方法将滤波重构后的瞬时转速波动信号角度域特征值进行聚类分析,并在机电液一体化平台上进行了变转速和变负载工况试验,实现了轴向柱塞泵配流盘在正常、轻微、严重磨损时的故障诊断。研究成果可为液压设备的运行状态监测与故障诊断提供新的方法。展开更多
基金supported by National Natural Science Foundation of China (No.51079033,No.60704004)the Fundamental Research Funds for the Central Universities (No.HEUCFR1009)
文摘In ships having two rudders, an angle error exists if there is a difference in structural and electrical parameters in two steering gear systems. Such an error also results in reduced efficiency of ship maneuverability during navigation. For the sake of reducing the angle error, a synchro-ballistic control approach based on cloud model is proposed in this paper. First, the mechanism model of steering gear system is introduced. Second, the structure of synchro-control system of twin-rudder is proposed based on the master-slave control strategy. Third, synchro-ballistic controller based on cloud model is designed to solve the nonlinearity and uncertainty of system. Finally, the designed controller is tested via simulation under two different situations. The simulated results demonstrate that this method is simple and has stronger robustness against the variation of states and parameters of plants. Hence, the validity and reliability of the method is proved for synchro-control of two rudders, which is a significant engineering application.
文摘To counter the strong disturbance caused by the rotation of steering axle, a synchro-compensation methodis proposed to absorb the generated disturbance now by driving the loading motor stator to make it synchronously rotatewith its axle. Through analyzing and discussing different kinds of synchro-compensation schemes, the determinedpassive position and speed synchro-compensation systems are designed and simulated by computer. The results prove thatthisa method is effective to eliminate the strong disturbance of the steering axle.
文摘Applying the air impact molding method to mold the complicated pattern with wider opening surface and deeper concave, there always exist vaulted phenomenon and lower compactibility of sand mold over the entrance and the concave regions. Using the air-stream and synchro-formed clamp plate impact molding, however, this problem will be preferably solved. In this paper, the compact mechanism of the new molding method and the effect of some configuration factors, such as the area flowed by compressed air and the highness of the protruding block displacement around the diffluent clamp plate, on the compactibility of sand mold were discussed.
文摘液压设备在运行过程中伴随着多域间的能量转换,尤其在变工况下呈现出非平稳性及非线性等特征,为状态监测与故障诊断带来难度。为了提高非平稳工况轴向柱塞泵故障诊断的性能,该研究提出采用既是运行参数又是状态参量的瞬时转速信号作为轴向柱塞泵故障诊断的信息源。通过理论分析得出瞬时转速信号的波动成分中蕴含着元件健康状态信息。提出采用同步提取标准S变换(synchro-extracting of normal S transform,SNST)对其进行线通滤波处理。利用K-medoids方法将滤波重构后的瞬时转速波动信号角度域特征值进行聚类分析,并在机电液一体化平台上进行了变转速和变负载工况试验,实现了轴向柱塞泵配流盘在正常、轻微、严重磨损时的故障诊断。研究成果可为液压设备的运行状态监测与故障诊断提供新的方法。
