Design and Driving Control of Cross-Scale Micro-Nano Coordinate Measuring Machine

In the field of advanced manufacturing, with the rapid development of micromachining and microelectromechanical systems, the demand for 3-D high-precision measurement is increasingly urgent. In order to address the contradiction between large-stroke motion and high-precision measurement, a new cross-scale micro-nano coordinate measuring machine (CSMN-CMM) is developed in this article. The measuring machine’s measurement method is with the probe fixed and the worktable (workpiece) moving. The metrology system consists of three-axis laser interferometers and an angle measurement system, which can measure the worktable’s spatial coordinates and posture in real time. The entire metrology system adheres to the Abbe principle and is also independent of the motion system, which avoids the influence of the motion system. The motion system comprises a 3-D large-stroke macro-motion stage and a six-degree-of-freedom (6-DOF) micro-motion stage, which can achieve high-precision and rapid driving of the worktable within a motion range of $100\times 100\times 100$ mm. The developed 6-DOF micro-motion stage is driven through piezoelectric ceramics. It can achieve more than $20~\mu $ m linear displacement for each axis with a resolution better than 0.56 nm and over $27^{\prime \prime }$ angular displacement with a resolution better than $0.09^{\prime \prime }$ . It ensures precise driving and spatial posture adjustment of the worktable. In terms of the control of the CSMN-CMM, this article proposes macro-micro collaborative positioning and secondary triggering strategies to enhance measurement performances. These strategies achieve positioning accuracy better than 6.4 nm and the repeatability of the probe better than 20 nm ( $k =1$ ) in the 3-D-direction. The maximum permissible error (MPE) of the CSMN-CMM is evaluated following ISO 10360–2, which is better than ±( $250+ 3.6\times 10^{-6}L$ ) nm. A series of experimental results shows that the developed CSMN-CMM has outstanding measurement performance in 3-D space. Its innovative structural design and key technologies are, furthermore, important for enhancing the current micro-nano-measurement technology.