Form error in-process optical measurement is to provide feedback during a machining process for precision control.
Based on the method of water beam assisted form error in-process optical measurement, a new air beam approach was
proposed to solve the problems of coolant dilution and optical transmittance through multiple media. In order to identify
key parameters to reduce the workload of experimental tests, a factorial test was conducted on transparent window size
At and stability est. Calibration and assessment of At and est were introduced. Factorial test design was also examined.
Results of the study show that vt, va, and da are the key parameters on At. Although all 6 main parameters are not
significant, vt is relatively more important on est. When vt increases, At will decrease. When va or da increases, At will
increase. The findings agree with our understanding of the physical process of fluid flow. When vt decreases, the
transparent window size stability est will be better. Consider both stability est and air velocity va, Run 11 should be the
best choice of conditions for At. A larger transparent window size At typically gives better transparent window size
stability est. To achieve a balance between est and va, a suitable size of transparent window at At=~30 mm2 should be a
good choice. Further studies are necessary to confirm the findings.