由于国内波纹管膨胀节波距检测还处于手工测量阶段，存在着效率差、精度低、劳动强度大等缺点。设计了基于激光扫描技术的波纹管膨胀节波距检测系统，提出一种波纹管膨胀节波形曲线拟合及波距检测的算法，开发了一种能够自动获取波纹管膨胀节伸缩变形的波形点云数据、并能实现波形的逆向重构及波距计算的软件。该系统适用于波纹管膨胀节通径50mm~1500mm、双试验件总长1500mm~2500mm、试验压力0.1MPa~6.4MPa范围内变化的试验件波形检测，可自动调整扫描仪至膨胀节的距离，并能剔除检测过程中出现的各种干扰数据，波距测量精度达0.05mm。
The measurement of wave pitch of bellows expansion joints is still in the manual vernier caliper measurement stage, which is not only inefficient, low precision, large labor intensity, but also many other shortcoming. In this paper, a waves pitch detection system of bellows expansion joints based on laser scanner technology was designed, a waveform fitting algorithm and wave pitch detection algorithm for bellows expansion joint was proposed, and a software automatically obtaining the point cloud data, conducting the waveform reconstruction and calculating wave distance had also been developed. The system is suitable for the bellows expansion joint test piece waveform detection, which diameter is from 50mm to 1500mm, the whole length of the double test pieces is from 1500mm-2500mm, and the test pressure is from 0.1MPa-6.4MPa, it can adjust the distance between the scanner and the expansion joints automatically, and eliminate all kinds of interference data, the measurement accuracy of wave distance is 0.05mm.
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