Method of Layered Line Tool Path Planning for Rough Machining Free-Form Surface
Numerical control rough machining with layered tool path planning demonstrates high machining efficiency and wide applicability.However,when processing free-form surface,there is a tendency to en-counter issues at the connections of adjacent tool paths,such as overcutting or excessive cutting allowances.For three-axis numerical control rough machining,a method of layered line tool path planning is proposed.It involves obtaining the surface contour on the machining plane,defining the machining area by intersec-ting the initial toolpath with the contour,and calculating interference-free cutter location points based on the local contour around the intersection points.The method searches for connecting cutter location points be-tween adjacent tool paths that do not interfere with the contour lines.For the connecting tool paths,a meth-od is proposed to calculate the step error with precision constraints and discrete characteristic points.By adding transitional cutter location points,the final connecting tool paths achieve step error below the maxi-mum allowable value.The proposed method generates tool paths for a part with free-form surface and simu-lates the machining process.The results validate the feasibility of the method.