摘要
数字化精密测量技术是数字化制造技术中的关键技术之一。三坐标测长仪作为几何尺寸数字化检测设备在机械制造领域得到推广使用,而科学研究和机械制造行业的技术进步又对三坐标测长仪提出更多新的要求,随着柔性三坐标测长仪的日益广泛应用,人们不仅关心测长仪的结构、原理和测量坐标的计算方法,同时更关心测长仪的精度分析及影响精度的各种因素。在柔性三坐标测量系统的理论分析基础上,推导出蛙跳式坐标转换方法,解决大尺寸零部件的测量问题,对蛙跳法进行论述,并建立坐标转换数学模型,推导出蛙跳后新坐标系相对原坐标系的坐标转换关系及n次蛙跳后的一般坐标转换公式。在引入矢量和矩阵的范数和条件数后,给出蛙跳后的测量误差的计算公式和坐标转换公式。在此基础上,分析蛙跳球的位置、蛙跳步长对大尺寸测量精度的重复影响,指出蛙跳球的最佳取位和每次蛙跳的最佳步长。
Digitized precision measurement technology is one of the key technologies in the digitized manufacturing technology. The three-coordinate measuring machine as digitized testing equipment for geometric size is extensively used in the machinery manufacturing, and the technological progress in scientific research and machinery manufacturing industries put forward more new requirements for the three-coordinate measuring machine. With the increasing application of flexible three-coordinate measuring machine, users are not only concerned with the structure and principle of the measuring machine, and the computation of measuring coordinates, but also more concerned with the accuracy analysis of the measuring machine and the factors that affect the accuracy. Based on the theoretical analysis of flexibile three-coordinate measuring system, the leapfrog type coordinate transformation method is derived so as to solve the problem of measuring large-size parts. The leapfrog method is discussed, the mathematical model of coordinate transformation is built, the coordinate transformation relationship between new and old coordinate systems after leapfrog, and the general coordinate transformation formula after n times of leapfrog are derived. After importing the norms and condition numbers of vector and matrix, the calculation formula of measuring error and the coordinate transformation formula after leapfrog are given. Based on this, the repeated affect of leapfrog ball position and leapfrog step on the large-size measuring accuracy is analyzed, and the best positioning of leapfrog ball and the best step of each time of leapfrog are indicated.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2009年第4期304-308,共5页
Journal of Mechanical Engineering
关键词
柔性三坐标测量
坐标转换
蛙跳步长
蛙跳位置
Flexible three-coordinate measurement Coordinate transformation Leapfrog step Leapfrog position
