An in-process measurement method for repair of defective microstructures by using a fast tool servo with a force sensor

Abstract

a b s t r a c tThis paper presents an in-process measurement method, which is capable of conducting real-time position identification and on-machine profile characterization of micro-defects in defective microstructures by using a fast tool servo with a force sensor (FS-FTS) on an ultra-precision lathe. A real-time thrust force map is captured in the process of cutting the microstructures by the FS-FTS to indicate the cutting status with respect to the cutting tool position in the coordinate system of the lathe. Based on the thrust force map, the positions of the defects are identified in real time from the locations of the abnormal variations in the map associated with the occurrences of the defects. Characterization of the defects is then conducted by employing the force-controlled cutting tool as the measuring probe to measure the sectional profiles of the defective microstructures. The identified positions and the characterized profiles of the defects are then fed back to carry out the repair fabrication of the defective microstructures with an accurate tool path. Experiments of in-process detection and repair of the micro-defects in the microstructures over the outer surface of a roll mold were carried out to confirm the feasibility of the proposed method.

On-machine and in-process surface metrology for precision manufacturing

“…22) [62]. Such measurement technology was also used for on-machine measurement of cutting edge contours of single point diamond tools [28] [25] and initial surface form of brittle workpieces [26] as well as for in-process measurement and repair of defective microstructures [29].…”

“…Feedback of the measured information to compensation machining of micro-structures is a challenging task due to the critical requirement on the positioning accuracy of the tool. Chen et al demonstrated the possibility of repairing defective microstructure elements on a large-area roll mould by using a FS-FTS [29]. The occurrence and the position of a defective element could be detected during the cutting process by the force sensor, and the sectional profile of the element could be characterized after the process, by using the tool itself as a force-controlled stylus probe.…”

Cutting force prediction for ultra-precision diamond turning by considering the effect of tool edge radius

“…It can be a factor causing cutting tool deflection in milling process, a signal for tool wear monitoring or repairing the defection of machined surface [1] and so on. Many cutting force models based on orthogonal cutting have been proposed to predict the cutting force [2,3,4].…”

Molecular dynamics simulation of elastic–plastic deformation associated with tool–workpiece contact in force sensor–integrated fast tool servo

“…This new type of on-machine measurement technology has demonstrated its effectiveness in various applications of fabrications of the micro-structured surfaces. 8,18–20…”

“…However, permanent contact marks with a depth of several nanometers have been confirmed in the previous research when the surfaces of soft metals such as copper and aluminum, which are the popular materials used in diamond cutting, are made to contact with the diamond tool in the current version of FS-FTS with a contact force measurement resolution of 0.06 mN and a tool displacement measurement resolution of 1 nm. 8,19…”