Machining centers have played a central role in the production field for nearly half a century. Accuracy inspections of machining centers are performed as per ISO standards; however, the accuracy performance of machining centers is often not checked directly after delivery to the factory unless there is a collision between a tool and a workpiece or product failure. Although positioning accuracy is fundamental to the performance of machining centers, the need for expensive laser interferometers and the time required for the setup present barriers to owning and inspecting them. This study proposes a simple method for measuring positioning accuracy that does not require a time-consuming setup of the measurement device or expensive devices. Therefore, the user of the machine tool can own and use the proposed method for daily inspection to identify changes in the positioning accuracy of the numerically controlled machine tool more quickly.

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