Straightness Measurement of Long Cylinder for Construction of Linear Collider

本研究的目的是开发一套高精度的直线度测量系统，为构建下一代直线对撞机做准备。这个直线对撞机长约20公里，将由三个长度为1.5米的圆柱体组成的部件对齐构建。为了将整个直线对撞机建造得足够直，必须将每个组件与大约10微米的直线度对准。为此，必须建立一种精确的测量系统，该系统可以测量长圆柱体的直线度，测量精度可达5米，精度可达几微米。考虑到精度与长度的比例和测量环境，扫描探头技术是满足这一要求的唯一途径。本研究提出了一种新的扫描多探头精密测量直线度轮廓的方法。这种扫描探针法是在传统的三探针法的基础上发展起来的，可以测量…的轮廓更准确，不受扫描工作台运动误差的影响。在三探针法中，探头间的调零误差是最大的误差源，到目前为止还没有很好的方法来准确地调整调零误差。在这项研究中，提出了一种新的方法，其中使用了两套三探针法传感器单元。两个传感器单元放置在对撞机组件的两侧，用于同时扫描组件的两个相对的母线。然后将部件中的一个圆柱体旋转180度，并由探头单元再次扫描。根据两次测量的输出数据，可以准确地评估零点调整误差以及零件的直线度轮廓。基于该方法搭建了一套实验装置，对5m长的对撞机部件进行了测量。使用了六个分辨率为几纳米的电容探头。探头距离设置为150 mm。整个零件的直线度测量精度达到了几个微米，这表明所开发的直线度测量系统是可行的。较少

The purpose of this study is to develop an accurate straightness measuring system for the purpose of constructing a next generation of linear collider. This linear collider is approximately 20km in length and is going to be constructed by aligning components consisting of three cylinders with a length of 1.5m. To construct the entire linear collider straight enough, it is necessary to align each component with a straightness in approximately 10 microns. For this purpose, an accurate measurement system, which can measure the straightness of long cylinders up to 5 m with an accuracy of several microns, must be established. Considering the ratio of accuracy to length and the measuring environment, scanning probe technique is the only approach to satisfy this request. In this study, a new scanning multi-probe method for accurately measuring straightness profiles has been developed. This scanning probe method is developed from the traditional three-probe method, which can measure the profil … More e accurately without the influence of motion errors of the scanning stage. In the three-probe method, zero-adjustment errors between probes are the largest error source, and so far there was no good methods to accurately adjust the zero-adjustment error. In this study, a new method was proposed, in which two sets of three-probe method sensor units are used. The two sensor units are placed in the two sides of the collider component and are used to scan the two opposed generatrices of the component simultaneously. One of the cylinders in the component is then rotated 180 degrees and scanned by the probe units again. The zero-adjustment error, as well as the straightness profiles of the component can be accurately evaluated from the output data of the two measurements. An experimental setup based on the proposed method was constructed to measure the collider component of 5m in length. Six capacitance probes with a resolution of several nanometers were employed. The probe distance was set to be 150 mm. The straightness of the entire component was measured with an accuracy of several microns, and this indicated the feasibility of the developed straightness measuring system. Less