Thermography-Based Investigation into Thermally Induced Positioning Errors of Feed Drives By Example of a Ball Screw

The following paper presents a method, based on thermographic measurements, to calculate the thermally induced positioning errors of feed drives in machine tools, here described with the example of a ball screw drive. Especially the effect of an uneven temperature distribution in the components on the total deformation is examined in this method. A transformation between the 3-D object space and the 2-D image space was created by means of digital image processing and photogrammetry as well as defined reference points on the structure of the feed drive with the surrounding machine components. The transformation enables the necessary identification of the defined structure points in the thermographic picture. With the help of the temperature information contained in the thermographic images, the respective thermally induced errors can then be calculated depending on the respective axial position by means of a temperature deformation model.