The article deals with measurement of pose repeatability of industrial robot Fanuc LR Mate 200iC. Laser interferometer Renishaw XL-80 and digital indicator Mitutoyo Absolute Digimatic ID-F are used for the measurement. The measurement methodology is based on so-called ISO cube placed in the most used part of robot workspace. Individual steps of the solution, the analysis of measurement data and results are presented in the article.

Position performance is one of most important parameters in terms industrial robotics and CNC machine tools. These performance criteria are changed during machine operation and therefore it is necessary to measure device parameters in regular intervals. This measurement should be as fast and easy as possible. In the case of CNC machine tools, the Renishaw Ballbar device is commonly used for such purposes. This device fits both requirements regardless it does not offer same amount of useful information for CNC machine tools and industrial robots that require special approach to measurement and data analysis which is main topic of presented article.

Renishaw Ballbar QC20–W is primarily intended for diagnostics of CNC machine tools, but it is also used in connection with industrial robots. In the case of standard measurement, when the measuring plane is parallel to the robot base, not all robot joints move. The purpose of the experiments of the present article was to verify the hypothesis of the motion of all the robot joints when the desired circular path is placed on an inclined plane. In the first part of the conducted experiments is established hypothesis is confirmed, through positional analysis on a simulation model of the robot. They are then carried out practical measurements being evaluated the influence of individual robot joints to deform the circular path, shown as a polar graph. As a result, it is found that in the case of the robot used, changing the configuration of the robot arm has the greatest effect on changing the shape of the polar graph.

The article discusses the possibility to identify changes in robot accuracy based on deformation of the circular path measured by the Renishaw Ballbar system. The research method utilizes correlation between industrial robot accuracy and precision of method used for the so-called calibration process. The presented experiments consist of two basic parts. The first is positional analysis with a simulation model of the robot in Creo Parametric 4.0. The second part describe practical measurements using the Renishaw Ballbar QC20-W and the Renishaw XL-80 laser interferometer. The results of the experiments confirm that Renishaw Ballbar can be used to quickly and simply identify occurrence of changes in the condition of an industrial robot.