Predictive compliance based model for compensation in multi-pass milling by on-machine probing

Abstract Process-intermittent gauging by on-machine probing detects errors due to the cutting action such as system deflection. Milled thin wall parts are particularly affected. A general model is presented which relies solely on probing data from semi-finishing cuts to compensate the final cut. A variable cutting compliance coefficient relates the total system deflection to the depth of cut. The effect of both changes in final depth of cut and the reduction in part compliance are anticipated by the model-based approach in order to more effectively compensate the final cut. Experimental validations for the milling of a straight thin wall and for a hole with variable wall thickness show that the compliance induced error is essentially eliminated using the proposed model compared to only 60% for a non compliance based approach.