Development of an automatic approaching trigger measurement system based on macro-micro collaborative motion

To solve the contradiction between the large-stroke motion of the stage and high-precision measurement, a Fast Automatic Approaching Trigger Measurement System (FAATMS) based on macro-micro cooperative motion is proposed herein. This system effectively combines a large-stroke macrostage (LSMS) and a six-degree-of-freedom microstage (6-DOFMS). A three-dimension (3D) motion control and nanoscale triggering method was adopted, involving the rapid movement of the LSMS and the cooperation of the 6-DOFMS for secondary triggering. Before measurement, the LSMS drives the sample to approach the probe quickly to realize a coarse triggering. After the first triggering is completed, the program is automatically switched to enter the 6-DOFMS control to achieve the second precise triggering. The 3D LSMS has a stroke of more than 100 mm × 100 mm × 100 mm. The designed 6-DOFMS is driven by hybrid series and parallel piezoelectric ceramic actuators. The interior adopts a hollow design and is used to install the stage for placing the measured sample, which can be effectively combined with the LSMS to achieve high-precision measurement tasks. The 3D displacement of the FAATMS is measured by laser interferometers. The three-axis laser beams converge on the probe and comply with the Abbe principle throughout the entire measurement range. Based on the secondary triggering strategy of the collaborative motion control of the macro-micro stages, the system drives the sample to trigger the probe ten times in each of the five directions of X+, X-, Y+, Y-, and Z. The peak-to-peak (PP) value of the repeatability measurements was 64.9 nm, and the standard deviation was less than 39.1 nm (k=2). By conducting precise measurements at the micro-nano level on the standard sphere, with a diameter repeatability of 330 nm (k=2), demonstrating the reliability and accuracy of this automatic approaching trigger method in practical applications can be re-evaluated. A series of experimental results show that the developed FAATMS is of great significance for improving the fundamental manufacturing technology and can provide a reference for precision measurement and high-end equipment manufacturing.