Laser Micromachining System Software Design

Laser micro-processing has been widely used due to its easy realization of processing conditions, high power density, broad processing objects and high automation. As a part of the Laser Micro Processing System, the project put forward and resolves issue in the design of system software as follows:Movement control setting value of track was formed by three modes:1. Obtaining of setting value of track based on observing of CCD. X-Y table, area being processed in the screen and observing area of CCD are strictly corresponding. The path of processing was obtained in observing of CCD.2. Obtaining of setting value of track of regular curve. Setting value of track was formed through characteristic data obtained by parameter input or information selected by mouse in screen.3. Obtaining of setting value of track based on image processing. The image, input by some image input device or edit through computer, was formed two-value image through image processing. The two-value image denoted by line form is setting value of track. In image processing, a method is put forward to get the better contour extraction of an image. The course is use the gray image, U heft of aberration image and V heft aberration image transformed from one color image contrast with each other to get the contour extraction of an image.Setting value of track was downloaded to controller through series port. The controller control step motor and step motor control X-Y table to move. The processing can be accomplished.There are quick-location mode and track-control mode in movement control. Step motor is controlled to acceleration and deceleration in quick-location mode. X-Y table move to desired position quickly and no overshooting controlled by step motor. Use the interpolation arithmetic let object move in uniform motion along the setting track in track-control mode. At the same time, the light source is turned on to process.There is inaccuracy in open loop control because step motor's desynchronizing, overshooting and return difference. The inaccuracy is over 100 m in movement scope ofX-Y table. In control software, close loop control was used by using the grating scale position signal as feedback. In this mode, accuracy is limited in 2 m.