Generation method and generation apparatus of tool path based on corrections using average distances

A method of machining a workpiece with a machine tool to provide a smoothed machined surface, including controlling the machine tool by generating a tool path by a control device for the machine tool at a time of machining the workpiece, comprising:

• providing a machine tool;
• providing a workpiece;
• generating a tool path for the machine tool including the steps of:
• a reading step of reading, by a program reading unit of the control device, a plurality of tool paths which are obtained by successively connecting a plurality of machining points with line segments in accordance with a predetermined rule based on shape data for machining the workpiece;
• a distance calculation step of calculating, by a distance processing unit of the control device, distances from a correction machining point to respective distance calculation points by determining one of the machining points as a correction machining point on the plurality of tool paths, which have been generated in the machining program generation step, by line segments;
• extracting tool paths, which are located within a predetermined range from the correction machining point, from the plurality of tool paths;
• and determining the distance calculation points on the extracted tool paths which are located within the predetermined range;
• an extraction step of extracting, by a data extracting unit of the control device, distance calculation points with distances calculated by the distance calculation step within a predetermined value;
• an average value calculation step of calculating, by an average value processing unit of the control device, an average value of position data of the distance calculation points extracted by the extraction step and position data of the correction machining point;
• and
• a data correction step of correcting, by a data correction unit of the control device, the position data of the correction machining point, by the average value calculated by the average value calculation step, and generating a plurality of new tool paths based on the corrected position data of the machining point;
• and
• machining the workpiece by moving the machine tool relative to the workpiece according to a new tool path,
• further including, successively changing the correction machining point from the one machining point to other machining points and repeating the distance calculation step, the extraction step, and the average value calculation step, for each correction machining point which is changed to calculate an average value of position data of each correction machining point, wherein the data correction step includes correcting the position data of each the correction machining point, by the average value of the position data of each the correction machining point, and generating a new tool path based on corrected position data of the machining points.