Self-calibration method for measuring system of three-dimensional large-stroke density workbench

The invention discloses a self-calibration method for a measuring system of a three-dimensional large-stroke density workbench, and belongs to the field of precise machining and measurement. The method comprises the following steps: performing self-calibration on the three-dimensional workbench on a regional basis respectively with a three-dimensional self-calibration principle by taking a cubic optical glass block with a uniform grid array as an auxiliary measuring device to obtain the system error of each region; performing system error compensation on corresponding regions; performing linear fitting on the obtained discrete point coordinate of each region; performing coordinate system correction processing on the calibration coordinate systems of adjacent regions in sequence according to a planned sequence to obtain a uniform calibration coordinate system in a whole region, and finishing self-calibration of the three-dimensional large-stroke density workbench measuring system finally. By adopting the method, the large-stroke and high-accuracy self-calibration of the three-dimensional workbench is realized; meanwhile, the function of the high-accuracy three-dimensional workbench is calibrated by using the cubic glass block with the low-precision grid array without any high-accuracy calibration tool, and high calibration accuracy is achieved; the method is suitable for calibrating various three-dimensional precise workbenches.