Straightness Measurement of Long Cylinder for Construction of Linear Collider

本研究旨在发展一套精密直线度量测系统，以配合下一代直线对撞机的发展。该直线对撞机长约20公里，将由三个长1.5米的圆柱体组成的组件对齐建造。为了将整个直线对撞机构造得足够直，有必要将每个部件以大约10微米的直线度对准。为此，必须建立一个精确的测量系统，该系统可以测量长达5米的长圆柱体的直线度，精度为几微米。考虑到测量精度与长度的比值以及测量环境，扫描测头技术是满足这一要求的唯一途径。本研究提出一种多测头扫描式精密测量直线度的新方法。扫描探针法是在传统的三探针法的基础上发展起来的， ...更多信息 e不受扫描平台运动误差的影响。在三测头法中，测头间的调零误差是最大的误差源，目前还没有很好的方法来精确调整调零误差。在这项研究中，提出了一种新的方法，其中使用两套三探针法传感器单元。两个传感器单元放置在碰撞器组件的两侧，用于同时扫描组件的两个相对母线。然后将部件中的一个圆柱体旋转180度并再次由探针单元扫描。根据两次测量的输出数据，可以准确地评估零调整误差以及部件的直线度轮廓。基于该方法构建了一套实验装置，对5 m长的对撞机部件进行了测量。六个电容探针的分辨率为几个纳米。将探头距离设置为150 mm，测量整个元件的直线度，精度达到几微米，这表明所开发的直线度测量系统的可行性。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