中文摘要：

针对内径为Ф100—150mm工业管道内检测的需求，设计了一种采用直流电机驱动、利用弹簧实现径向尺寸主、被动调节的定心系统。在介绍了工作原理及机构组成的基础上，对系统各组件的力学特性进行了分析。利用ADAMS软件建立了定心系统的虚拟样机运动学仿真模型，得到了系统运行时偏心位移和移动速度的变化曲线。仿真表明，该系统能顺利通过水平放置的“L”型管道，定心精度可达0．2mm／1，水平直管移动速度为500mm／s，具有良好的稳定性。

英文摘要：

In order to satisfy the need of intemal inspection for the industrial pipelines whose diameters range from 100 to 150mm, a centering system is designed in this paper. The presented system is driven by a DC motor, and by using some springs, its radial dimension can be adjusted actively and passively. Based on the system＇s operating principle and mechanism structure, mechanical characteristics of each component are analyzed. After that, with the help of ADAMS software, the virtual prototype model is established and kinematical simulation is performed, which shows the time evolution of the system＇s eccentric displacement and moving velocity. Simulations also demonstrate that the system can pass the horizontal placed L-type pipe with 0.2 mm centering accuracy, 500 mm/s moving speed in horizontal straight part and a good stability.