分数阶PID控制器较传统整数阶PID控制器增加了2个可调参数,使得其控制器的设计更加灵活,控制性能更加优良.针对网络控制系统(NCS)中的时延以及数据包丢失问题,提出对系统采用分数阶PID控制方法进行补偿,利用MATLAB/True Tim e仿真工具箱...分数阶PID控制器较传统整数阶PID控制器增加了2个可调参数,使得其控制器的设计更加灵活,控制性能更加优良.针对网络控制系统(NCS)中的时延以及数据包丢失问题,提出对系统采用分数阶PID控制方法进行补偿,利用MATLAB/True Tim e仿真工具箱对NCS进行仿真研究.仿真实验结果表明,采用分数阶PID控制方法可以对时延以及数据包丢失问题进行有效的补偿,且控制效果明显优于整数阶PID方法.展开更多
Nugget splash during aluminum alloys spot welding has a detrimental effect on weld nugget integrity, strength and durability of the welded joints. This investigation is performed to identify nugget splash from voltage...Nugget splash during aluminum alloys spot welding has a detrimental effect on weld nugget integrity, strength and durability of the welded joints. This investigation is performed to identify nugget splash from voltage signals because these are easily accessible on-line. In the present work, we propose a novel method based on the wavelet packet transform and its energy spectrum for pattern recognition of splash signal. The result demonstrates that this novel method is more accuracy and a useful way of monitoring the spot welding quality.展开更多
文摘分数阶PID控制器较传统整数阶PID控制器增加了2个可调参数,使得其控制器的设计更加灵活,控制性能更加优良.针对网络控制系统(NCS)中的时延以及数据包丢失问题,提出对系统采用分数阶PID控制方法进行补偿,利用MATLAB/True Tim e仿真工具箱对NCS进行仿真研究.仿真实验结果表明,采用分数阶PID控制方法可以对时延以及数据包丢失问题进行有效的补偿,且控制效果明显优于整数阶PID方法.
基金This work is supported by Nature Science Foundation of Peo-ple ' s Republic of China ( No.50045019).
文摘Nugget splash during aluminum alloys spot welding has a detrimental effect on weld nugget integrity, strength and durability of the welded joints. This investigation is performed to identify nugget splash from voltage signals because these are easily accessible on-line. In the present work, we propose a novel method based on the wavelet packet transform and its energy spectrum for pattern recognition of splash signal. The result demonstrates that this novel method is more accuracy and a useful way of monitoring the spot welding quality.
