2D Scan-Head Motion Characterization and Machine-Tool Integration

Abstract

This work is focused in the integration of a scan-head in a machine tool for laser processing of large areas. The scan-head is a device typically used for marking operations and provides very high linear speeds. Despite scanners present high accuracy for marking speeds below 5,000 mm/s, over this limit, accuracy problems were found. In this kind of device the motion is controlled using high precision actuators but there is no positioning closed-loop and workspace area is typically limited to small working areas. On the other hand, the positioning error varies also with working area plane positioning. This becomes a problem for processing complex shape surfaces. The work presented deals with characterization of the scan head, to identify the parameters affecting the error, the influence of the error with working plane positioning and with the integration of fast rotary axes of the scan head with conventional linear axes of a machine-tool. The proposed solution is based on a NC parent program controlling the linear axis of the machine-tool with integrated subprograms that control rotary axes of the scan-head.