A numerical controller controls a machine tool with a plurality of control axes so as to compensate an inward turning error by inserting a curved movement path into a corner section between two consecutive blocks. An estimated inward turning amount generated as the corner section is subjected to post-interpolation acceleration/deceleration is calculated based on the radius of curvature of the curve and allowable accelerations of the axes of the machine tool, and such a curved movement path that its inward turning amount has a value obtained by subtracting the estimated inward turning amount from a tolerance is inserted into the corner section if the sum of the estimated inward turning and the inward turning amount of the curve is larger than the tolerance.

In the case where the shape of a machining path generated by analyzing a machining program includes a concave arc corner portion, the machining path is compensated by inserting a path leading from the end point to the start point of the concave arc along a path inside the concave arc and leading from the start point to the end point of the concave arc on the concave arc again.

A numerical controller having a function of optimizing a corner path at a corner of tangent continuity includes a path conversion unit for obtaining a curved correction path passing through three points corresponding to a start point and an end point of a third block, and a shift point obtained by shifting an intermediate point of a command path based on the third block in an inward direction of a corner path within a limit of a preset allowable error amount when the corner path is formed by a series of blocks and a tangential direction of the corner path is continuous, and generating a path obtained by replacing the command path of the third block included in the corner path by the correction path, the third block commanding curvilinear movement at a larger curvature than a first curvature and a second curvature being interposed between the first block commanding rectilinear movement or curvilinear movement at the first curvature corresponding to a small curvature and the second block commanding rectilinear movement or curvilinear movement at the second curvature corresponding to a small curvature in the series of blocks.

In a corner portion formed at an intersection of a first block to be machined first and a second block to be machined second, an end point of the first block is extended. Then, after moving from the first block to the extended end point of the first block, a wire electrode of an electrical discharge machine returns to an end point of the original block (an end point of the original first block and a start point of the original second block) therefrom along the same path as before, and machines the second block therefrom.

A machine learning device performs machine learning on a numerical control device which, when a first command including a corner portion, composed of two blocks in the machining program, generates a second command in which the two blocks are replaced with m or more blocks. The machine learning device comprises: a state information acquisition unit for acquiring state information including the first command, coordinate values of each block in the m or more blocks, and location information of the machining path and the machining time; an action information output unit for outputting action information; a reward output unit for outputting a reward value based on the inward turning amount in the corner portion; and a value function updating unit for updating a value function based on the value of the reward outputted from the reward output unit, the state information and the action information.

A control device for a wire electric discharge machine includes: a shape analysis portion which looks ahead a machining program, and analyzes a machined shape of a workpiece; a machining path creation portion which creates machining paths of identical circular arc shape offsetting from a machined shape analyzed, wherein the offset value differs for the machining paths, and shape of a corner part are identical circular arc shape; a machining path creation portion which creates machining paths of concentric circle shape offsetting from a machined shape analyzed, wherein the offset value differs for the machining paths, and shape of a corner part are concentric circle shape; and a machining path selection portion which selects either of the machining paths of identical circular arc shape and concentric circle shape, based on at least one among the machining program, machined shape analyzed, and the machining paths of identical circular arc shape and concentric circle shape.

A machine learning device performs machine learning on a numerical control device which, when a first command including a corner portion, composed of two blocks in the machining program, generates a second command in which the two blocks are replaced with m or more blocks. The machine learning device comprises: a state information acquisition unit for acquiring state information including the first command, coordinate values of each block in the m or more blocks, and location information of the machining path and the machining time; an action information output unit for outputting action information; a reward output unit for outputting a reward value based on the inward turning amount in the corner portion; and a value function updating unit for updating a value function based on the value of the reward outputted from the reward output unit, the state information and the action information.

A control device for a wire electric discharge machine includes: a shape analysis portion which looks ahead a machining program, and analyzes a machined shape of a workpiece; a machining path creation portion which creates machining paths of identical circular arc shape offsetting from a machined shape analyzed, wherein the offset value differs for the machining paths, and shape of a corner part are identical circular arc shape; a machining path creation portion which creates machining paths of concentric circle shape offsetting from a machined shape analyzed, wherein the offset value differs for the machining paths, and shape of a corner part are concentric circle shape; and a machining path selection portion which selects either of the machining paths of identical circular arc shape and concentric circle shape, based on at least one among the machining program, machined shape analyzed, and the machining paths of identical circular arc shape and concentric circle shape.

A numerical controller includes a path conversion unit for obtaining a curved correction path passing through three points corresponding to a start point and an end point of a third block, and a shift point obtained by shifting an intermediate point of a command path based on the third block in an inward direction of a corner path within a limit of a preset allowable error amount when the corner path is formed by a series of blocks and a tangential direction of the corner path is continuous, and generating a path obtained by replacing the command path of the third block included in the corner path by the correction path, the third block commanding curvilinear movement at a larger curvature than a first curvature and a second curvature being interposed between the first block.

A method for generating a robot program for a robot includes generating a robot program for traversing a robot path, the program having a plurality of movement sets for specifying the path, at least one of which has a specified target pose of a reference of the robot. At least one of the movement sets is a grinding set for which a grinding pose as a virtual starting pose for a successive movement set, an approach to a path section specified by the successive movement set, and an approach from a path section specified by a preceding movement set can be parameterized. A robot path may be traversed by a robot by executing the generated robot program.