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Dabiri Farahani, Nima

University of British Columbia

Machining processes are widely used to achieve the net shape of the parts in the industry. To plan the process with desired productivity and accuracy, the mechanics and dynamics of machining operations must be modeled to predict the cutting forces, torque, power of the spindle, and deflection marks left on the cut surface. Namely milling, drilling, boring, and turning, all machining processes remove layers of the workpiece to achieve the final product. Due to the similarities between different machining operations in terms of the cutting principles, they are generalized in one mathematical model to predict the cutting mechanics and dynamics in this thesis. Although operations are varied in terms of tool setup and configurations, all the tools are modeled through basic CAD elements and combined to achieve the final tool assembly. Considering the tool and workpiece's relative translational and rotational motions, the process types are determined automatically, and cutting engagement angles in the contact zone are interpreted from the tool CAD model, addressing all the geometrical features. A unified kinematics model is proposed to predict the cutting forces, spindle torque, and deflection marks left on the cut surface. The process kinematics are also used for a fast and acceptably accurate prediction of the chatter stability in the frequency domain. The results of the developed generalized physics-based model are presented for multiple industrial applications, including milling, drilling, boring, and turning operations. The simulated cutting mechanics and chatter stability charts predicted by the analytical model are demonstrated to be valid through comparisons with experimental measurements and existing data available in the literature. The proposed generalized model allows the planners to predict and optimize the 3-axis machining operations by avoiding costly trial and error-based tests in the industry.

Text

2021-12-14

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/80444

Mechanical Engineering

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/