%A FENG Wenlong,HUANG Yiqiao,TUO Zhanyu,LI Huimin,YANG Jianguo %T Modeling of Thermally Induced Grating Positioning Error of Large Machine Tools Based on Temperature Integral Method %0 Journal Article %D 2016 %J Journal of Shanghai Jiao Tong University %R %P 710-715 %V 50 %N 05 %U {https://xuebao.sjtu.edu.cn/CN/abstract/article_41259.shtml} %8 2016-05-28 %X Abstract： To decrease the grating positioning error of large machine tools, a novel modeling theory based on thermal characteristic analysis with its compensation method were proposed. The case of the error was analyzed to be the thermal deformation of the grating scale, whose manifestations were discussed. By analyzing the thermal characteristic, the mathematical expression between the elongation of grating scale and the variation of temperature was established. Several temperature sensors were installed on the grating scale, with which the temperature of grating scale were recorded. The temperature of each point on the grating scale were calculated by interpolating between adjacent sensors. The thermally induced positioning error of the grating scale model was established by conducting the integral for the variations of position and temperature. By using the developed compensation system, the compensation for floor type borer TK6920 was implemented by applying the established model. The results show that the thermally induced positioning error of the grating scale has been decreased by 90% and the residual error is less than 1.5 μm/m. The positioning accuracy of the grating scale is significant improved.