Workspace digitization for five-axis machining

摘要

While performing five-axis machining, it is usually expected to complete all the cutting without having to re-clamp the workpiece. In other words, the workpiece should remain at the same location during the whole five-axis machining process. The current procedure to perform five-axis machining on a workpiece is to use CAM software to generate the tool paths and then perform a simulation or real cutting to verify if it is possible to complete the machining process without having to re-clamp the workpiece. If the simulation or the actual cutting fails to achieve this, the trial-and-error method is usually introduced to adjust the location of the workpiece. Then we need to rerun the simulation or actual cutting to verify the adjustment. The trial-and-error process can be time-consuming, and there is no guarantee that a viable location can be obtained. The objective of this research was to develop a method to establish the workspace for a workpiece on a five-axis machine. It can guarantee that no re-clamping is needed as long as the workpiece is placed in the final workspace. First, we construct a preliminary workspace based on the travel limits and the location of all the interpolation points along the cutting paths. Then we obtain the keep-out zones so that the collision between the cutting tool and the worktable will not occur as long as the workpiece origin is outside the keep-out zones. Finally, the workspace without travel-limit or collision problems can be obtained by subtracting the keep-out zones from the preliminary workspace. The workspace is digitized to facilitate the calculation and visualization. In the end, a case study was conducted to illustrate how to apply the method to a real task. It was shown that workspace obtained by using the method was free of the mentioned problems.