作　　者： (徐舟）; (李群明）;

机构地区： 中南大学机电工程学院,湖南长沙410083

出　　处： 《机械工程与自动化》 2017年第5期1-3,6,共4页

摘　　要： 样品位姿的确定是对样品进行中子衍射测量的前提。针对中子衍射残余应力测量的样品存在复杂曲面的情形,为得到激光扫描仪建立的样品坐标系相对全站仪坐标系的位姿矩阵,采用基于基准点的样品位姿标定方法进行实现。首先分析了基于基准点的样品位姿标定过程,然后应用刚体变换法确定出样品相对全站仪坐标系的位姿矩阵,并针对基准球、角点、中心孔三种基准点类型进行了实验。精度评定分析表明:基于基准球的对齐精度均方根值RMS最小,角点次之,中心孔最大。因此,选择基于基准球的方法最优,所确定的样品位姿可用于后续中子衍射测量实验。最后,利用IDL语言实现了样品位姿可视化。 The determination of the orientation and pose of sample is a premise before neutron diffraction. To address the issue that sample surface may be complex in neutron diffraction,in order to obtain coordinate transformation matrix of sample coordinate system established by laser scanner relative to the total station coordinate system, the paper uses the method based on fiducial point to achieve samplealignment. Firstly, the process of sample alignment based on fiducial point is analyzed, and the experiment is carried out for three kinds of fiducial points of fiducial ball, corner point and center punch. Then the rigid body transformation method can be used to determine orientation and pose matrix of sample relative to the total station coordinate system. The accuracy analysis shows that the RMS of alignment accuracy based on fiducial ball is minimum, the corner is followed, center punch is the largest. Thus, the method based on fiducial ball is optimal, and determined sample pose can be used for subsequent neutron diffraction. Finally, the IDL language is used to visualize the sample pose.

关 键 词： 基准球 样品位姿标定 刚体变换法 可视化