Adaptive milling of solid wood furniture workpieces: analysis of the extended approach capabilities

An extended approach to improve adaptive milling of solid wood workpieces is described. It is based on the joint usage of two physically different methods: non-contact ultrasonic scanning of the workpiece body and optical recognition of the wood fibers direction on the workpiece surface. To implement the proposed approach, it is necessary to change the existing technological route of furniture workpieces processing. A stage before the milling operation should be included. This stage involves the sequential execution of ultrasonic scanning, computer processing, and optical recognition of the obtained data. It allows us to determine the wood density, the internal defects localization, and the direction of wood fibers. Computer processing involves the usage of a virtual orthogonal grid. This grid covers the workpiece surface, on which the trajectory of the milling cutter is projected. The projection of the milling path is represented by the set of cells. It defines the local processing area. The gathered information about the wood properties is suggested to use for the adaptive selection of the important equipment technological parameters, such as the feed rate and the cutter rotation frequency. Varying of these parameters values and considering the physicomechanical properties of wood at the processing area allow us to improve the milling quality.