ACFM(Alternating Current Field Measurement,交流电磁场检测)技术是通过测量磁场的变化探测裂纹并测定裂纹尺寸的一种无损检测方法。近几年来,国内海洋工程行业引进了ACFM设备进行水下结构件检测工作。介绍了利用U31型检测设备对水下...ACFM(Alternating Current Field Measurement,交流电磁场检测)技术是通过测量磁场的变化探测裂纹并测定裂纹尺寸的一种无损检测方法。近几年来,国内海洋工程行业引进了ACFM设备进行水下结构件检测工作。介绍了利用U31型检测设备对水下铁磁构件实施ACFM检测的试验情况,对检测中得到的显示图谱进行了分析,总结了不同的相关显示和非相关显示的图谱特征,并编制了一个用于检测缺陷判定的工艺流程,用于实际检测时帮助识别缺陷。展开更多
A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous ...A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous underwater vehicle(PDAUV) is hereby designed to solve these problems when working with advanced optical,acoustical and electrical sensors for underwater pipeline detection.PDAUV is a test bed that not only examines the logical rationality of the program,effectiveness of the hardware architecture,accuracy of the software interface protocol as well as the reliability and stability of the control system but also verifies the effectiveness of the control system in tank experiments and sea trials.The motion control system of PDAUV,including both the hardware and software architectures,is introduced in this work.The software module and information flow of the motion control system of PDAUV and a novel neural network-based control(NNC) are also covered.Besides,a real-time identification method based on neural network is used to realize system identification.The tank experiments and sea trials are carried out to verify the feasibility and capability of PDAUV control system to complete underwater pipeline detection task.展开更多
文摘ACFM(Alternating Current Field Measurement,交流电磁场检测)技术是通过测量磁场的变化探测裂纹并测定裂纹尺寸的一种无损检测方法。近几年来,国内海洋工程行业引进了ACFM设备进行水下结构件检测工作。介绍了利用U31型检测设备对水下铁磁构件实施ACFM检测的试验情况,对检测中得到的显示图谱进行了分析,总结了不同的相关显示和非相关显示的图谱特征,并编制了一个用于检测缺陷判定的工艺流程,用于实际检测时帮助识别缺陷。
基金Project(2011AA09A106)supported by the Hi-tech Research and Development Program of ChinaProject(51179035)supported by the National Natural Science Foundation of ChinaProject(2015ZX01041101)supported by Major National Science and Technology of China
文摘A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous underwater vehicle(PDAUV) is hereby designed to solve these problems when working with advanced optical,acoustical and electrical sensors for underwater pipeline detection.PDAUV is a test bed that not only examines the logical rationality of the program,effectiveness of the hardware architecture,accuracy of the software interface protocol as well as the reliability and stability of the control system but also verifies the effectiveness of the control system in tank experiments and sea trials.The motion control system of PDAUV,including both the hardware and software architectures,is introduced in this work.The software module and information flow of the motion control system of PDAUV and a novel neural network-based control(NNC) are also covered.Besides,a real-time identification method based on neural network is used to realize system identification.The tank experiments and sea trials are carried out to verify the feasibility and capability of PDAUV control system to complete underwater pipeline detection task.
