On-Machine Estimation of Workpiece Deformation for Thin-Structured Parts Machining

Abstract

The workholding process in small batch production is one of the least automated processes in machining. In order to ensure appropriate workholding, it is necessary to estimate actual deformation of the workpiece. Recently, near net shape technologies, such as thin-wall casting and additive manufacturing, have become common. Increased requirements for the finish machining of thin-structured parts has increased the need for the appropriateness of workholding to be evaluated. An objective of this study is to investigate an on-machine estimation method that can evaluate the actual deformation of parts with thin-structures. Thin-structured parts are usually held by means of multipoint fixturing or vise fixturing. A hybrid estimation method combining FEM analysis and local strain measurements is adopted to estimate the deformation. The effectiveness of the proposed method is evaluated with example problems. The results indicate the feasibility of the on-machine estimation of the deformation of thin-structured parts.