Magnetic tracking technologies have a promising application in detecting the real-time position andattitude of a capsule endoscope.However,most of them need to measure the magnetic moment of a permanentmagnet(PM)embed...Magnetic tracking technologies have a promising application in detecting the real-time position andattitude of a capsule endoscope.However,most of them need to measure the magnetic moment of a permanentmagnet(PM)embedded in the capsule accurately in advance,which can cause inconvenience to practical application.To solve this problem,this paper proposes a magnetic tracking system with the capability of measuring themagnetic moment of the PM automatically.The system is constructed based on a 4×4 magnetic sensor array,whose sensing data is analyzed to determine the magnetic moment by referring to a magnetic dipole model.Withthe determined magnetic moment,a method of fusing the linear calculation and Levenberg-Marquardt algorithmsis proposed to determine the 3D position and 2D attitude of the PM.The experiments verified that the proposedsystem can achieve localization errors of 0.48 mm,0.42 mm,and 0.83 mm and orientation errors of 0.66◦,0.64◦,and 0.87◦for a PM(∅10 mm×10 mm)at vertical heights of 5 cm,10 cm,and 15 cm from the magnetic sensorarray,respectively.展开更多
为进一步提升地铁转向架P355NL1钢材的熔化极活性气体保护(Metal active gas,MAG)多层焊焊接质量,开展了P355NL1钢地铁转向架对接接头MAG多层焊接试验,分析了对接结构的宏观及微观形貌,重点研究了每一层的焊缝及热影响区的组织,建立了...为进一步提升地铁转向架P355NL1钢材的熔化极活性气体保护(Metal active gas,MAG)多层焊焊接质量,开展了P355NL1钢地铁转向架对接接头MAG多层焊接试验,分析了对接结构的宏观及微观形貌,重点研究了每一层的焊缝及热影响区的组织,建立了对接接头MAG多层焊接模型并进行校核,探明了MAG多层焊温度场的分布规律。结果表明,在MAG多层焊接试验中,后道焊缝的热输入通过两次相变重结晶作用,破坏了前道焊缝中的柱状晶结构,此过程使得前道焊缝晶粒细化,形成了细小的铁素体晶粒和少量珠光体。双椭球热源模型可以有效模拟P355NL1钢MAG多层焊焊接过程,后道焊缝焊接时最高温度显著升高,因此在多层焊的焊接过程中,控制填充层的焊接温度对于细化晶粒组织至关重要。展开更多
基金the National Natural Science Foundation of China(Nos.52275038 and 61803347)the Shanxi Province Science Foundation for Excellent Youth(No.202203021224007)+1 种基金the Key Research and Development Plan of Shanxi Province(No.201903D321164)the Opening Foundation of Shanxi Key Laboratory of Advanced Manufacturing Technology(No.XJZZ202101)。
文摘Magnetic tracking technologies have a promising application in detecting the real-time position andattitude of a capsule endoscope.However,most of them need to measure the magnetic moment of a permanentmagnet(PM)embedded in the capsule accurately in advance,which can cause inconvenience to practical application.To solve this problem,this paper proposes a magnetic tracking system with the capability of measuring themagnetic moment of the PM automatically.The system is constructed based on a 4×4 magnetic sensor array,whose sensing data is analyzed to determine the magnetic moment by referring to a magnetic dipole model.Withthe determined magnetic moment,a method of fusing the linear calculation and Levenberg-Marquardt algorithmsis proposed to determine the 3D position and 2D attitude of the PM.The experiments verified that the proposedsystem can achieve localization errors of 0.48 mm,0.42 mm,and 0.83 mm and orientation errors of 0.66◦,0.64◦,and 0.87◦for a PM(∅10 mm×10 mm)at vertical heights of 5 cm,10 cm,and 15 cm from the magnetic sensorarray,respectively.
文摘为进一步提升地铁转向架P355NL1钢材的熔化极活性气体保护(Metal active gas,MAG)多层焊焊接质量,开展了P355NL1钢地铁转向架对接接头MAG多层焊接试验,分析了对接结构的宏观及微观形貌,重点研究了每一层的焊缝及热影响区的组织,建立了对接接头MAG多层焊接模型并进行校核,探明了MAG多层焊温度场的分布规律。结果表明,在MAG多层焊接试验中,后道焊缝的热输入通过两次相变重结晶作用,破坏了前道焊缝中的柱状晶结构,此过程使得前道焊缝晶粒细化,形成了细小的铁素体晶粒和少量珠光体。双椭球热源模型可以有效模拟P355NL1钢MAG多层焊焊接过程,后道焊缝焊接时最高温度显著升高,因此在多层焊的焊接过程中,控制填充层的焊接温度对于细化晶粒组织至关重要。
