基于解耦并联机构的核主泵螺栓检测环形平台粗精两级快速调整

Coarse and Fine Two-stage Fast Adjustment of the Ring Platform for Reactor Coolant Pump Bolt Detection based on Decoupling Parallel Mechanism

环形平台作为核主泵螺栓在线检测的移动和操作基准,其位姿快速、高精度调整是螺栓在线精确检测的关键。针对辐射环境环形平台位姿调整需求,提出了基于解耦并联机构的粗、精两级高精度快速调整方法,第一级粗调以6自由度解耦并联机构对环形平台进行初步调整,第二级精调以两独立方位特征子集对应的1T2R和2T1R解耦并联机构对平台按序进行水平度和同轴度调整;基于方位特征集理论,综合了粗、精两级调整解耦并联机构;提出了以海绵吸具在泵体弧形光滑外壁吸附形成固定支点,构造并联机构定平台,实现了各并联机构的快速安装、切换及拆卸。基于解耦并联机构的粗精两级快速调整,为实现核辐射环境环形平台的快速高精度调整提供了新思路。

The ring platform serves as the movement and operating benchmark for the online inspection of the nuclear reactor coolant pump bolts,its rapid and high-precision adjustment is the key to whether the bolt online inspection can proceed successfully.Aiming at the needs of adjusting the position and orientation of the ring platform in the radiation environment,a coarse and fine two-stage high-precision fast adjustment method based on the decoupling parallel mechanism is proposed.The first stage adjustment uses the 6-DOF decoupling parallel mechanism to coarsely adjust the ring platform.The second stage fine adjustment uses the 1 T2 R and 2 T1 R decoupling parallel mechanisms corresponding to the two independent position and orientation characteristic subsets to sequentially adjust the levelness and coaxiality of platform.The coarse and fine adjustment decoupled parallel mechanisms are synthesized based on the theory of position and orientation characteristic set.It is proposed that the fixed fulcrum of parallel manipulator can be constructed by means of the sponge-vacuum-device’s absorbing on the smooth cylindrical wall of the nuclear pump body.Based on the sponge vacuum device,the parallel mechanism is constructed,which can realize the rapid installation,switching and disassembly of each parallel mechanism.The fast adjustment of coarse and fine two stages based on decoupled parallel mechanism provides new ideas for realizing the rapid and high-precision adjustment of the ring platform in the nuclear radiation environment.