Time domain simulation of modulated tool path turning for surface finish prediction

Understanding surfaces created during finish machining operations is critical to the proper function of components. Methods for predicting surfaces in traditional turning are insufficient for surfaces generated by modulated tool path (MTP) turning. This project predicts MTP turning surface finish using a time domain simulation that solves the second order time delayed differential equations which describe the process. The time domain simulation incorporates the modulated tool path motion, workpiece and tool dynamics, material side flow effects, and spindle speed changes for constant surface speed turning of non-constant diameter parts. A new modeling approach for side flow and its influence on surface finish is described. The effect of coolant on side flow is also investigated. This work builds on prior MTP modeling efforts by including an extended side flow model and two axes of motion for tapered and curvilinear part geometries. Finally, a method for implementing the new time domain simulation capabilities into the current MTP workflow is described. This work advances surface finish prediction for MTP finishing operations. The outcome is improved productivity and reduced testing for optimum parameter selection when using MTP tool paths for finishing operations.