为了解决大孔径的高精度检测问题,介绍了一种激光非接触式大尺寸内径自动测量系统。该系统具有灵活可控的运动机构、稳定可靠的定心机构、同步伸缩的支撑机构、对称协调的扫描机构,可实现轴向自动行走、高精度同轴定位和快速扫描测量。高可靠性的控制系统和无线传输模式使其实现了远距离的实时控制和可靠性测量。高精度的温度采集模块实时监测环境温度的变化,便于温度补偿。以VC++为平台的上位机软件,集数据处理与实时显示于一体,操作极其方便。另外,该系统采用相对测量原理、高精度激光位移传感器与标定好尺寸的测量臂相结合,使系统测量范围达到φ580~998mm。高精度的激光位移传感器实现系统的非接触式内径测量,测量精度高。通过对比实验和现场实验对系统的测量精度和重复性进行了验证。结果表明:系统的测量精度与FARO激光跟踪仪测量结果比较差值小于6μm,现场测量重复性精度小于7μm。能够实现管道内径几何参数的测量和管道表面的几何评估及校正。
In order to solve the problem of large aperture high-precision detection, a laser non-contact automatic measuring system for large-scale inner diameter was introduced . The system was composed of a flexible and controllable crawling mechanism, a stable and reliable centering mechanism, a retractable supporting mechanism and a synchronized scanning mechanism. All the mechanisms make this system realize axial automatic movement, high-precision coaxial positioning and rapid scanning measurement. Remote real-time control and high-precision measurement were realized by high-reliability control system and wireless transfer mode. Temperature change was monitored by high-precision temperature gathering module in real time. Temperature error was easy to contained data processing and timely display was easy compensate. PC software based on VC++ which to operate. The measurement range of the system was up to φ580-φ998mm, by means of the principle of relative measurement which combined the high- precision laser displacement sensor and the pre-calibration measuring arm. Non-contact inner measurement was realized by the high-precision laser displacement sensor with high measurement precision. Measuringprecision and repeatability of the system was verified through contrast experiments and field experiments. Compared with FARO laser tracer, the difference of measuring precision between two systems is less than 6 μm. Repeatability of this system is less than 7 p~m.The system can measure the geometric parameters of the pipe diameter, and enable evaluation and correction of geometric surface pipeline.