Patent ID: 8175861

Claim:
A machining simulation method of performing a machining simulation according to an NC program in a machine tool having tool holding means for holding a tool, workpiece holding means for holding a workpiece, drive means for operating one or both of the holding means, drive control means for controlling the operation of the drive means according to operation commands for the one or both of the holding means extracted from the NC program, and screen display means for displaying image data, the machining simulation method comprising: an actual operation step in which one or both of the holding means is actually operated by controlling the drive means by means of the drive control means according to the operation commands, the one or both of the holding means being operated in a state where one or both of them do not hold the tool or the workpiece; an actual image generating step in which the tool holding means and the workpiece holding means during the actual operation are imaged by actual imaging means from a predetermined view point at a certain time interval and actual two-dimensional image data thereof is generated in turn; a model generating step in which, on the basis of data on three-dimensional models of the holding means, the tool and the workpiece, three-dimensional model data for the holding means, the tool, and the workpiece being in a state where their corresponding three-dimensional models are continuously operated synchronously with the actual operation of the holding means according to the operation commands is continuously generated in turn; a virtual image generating step in which a three-dimensional space is virtually set, virtual imaging means having the same condition as the actual imaging means is virtually arranged in the virtual three-dimensional space and the three-dimensional models of the tool and the workpiece continuously generated in the model data generating step are arranged in the same virtual three-dimensional space while being updated in turn, and virtual two-dimensional image data which is obtained when the three-dimensional models of the tool and the workpiece are imaged by the virtual imaging means from the same view point and at the same timing as those of the actual imaging means is generated in turn; and a rendering step in which the actual two-dimensional image data and the virtual two-dimensional image data at the same timing generated in the actual image generating step and the virtual image generating step, respectively, are synthesized and composite image data in which a virtual two-dimensional image of the virtual two-dimensional image data is superimposed on an actual two-dimensional image of the actual two-dimensional image data is generated in turn and displayed on the screen display means.