Mechanical analysis of a motor test bench under consideration of alignment errors

DFKI is setting up a motor test bench to characterize the robotic drives developed in-house. The measurement can be influenced by torsional vibrations and alignment errors. Therefore, it is necessary to analyze the setup mechanically to minimize the measurement errors. For this purpose, the natural frequency of the measuring section must be known in order to determine an optimal coupling between the load machine and the sensor as well as between the sensor and the test specimen with respect to the stiffnesses. Alignment errors of the test specimen can additionally load the sensor with lateral forces, this must be avoided. With a suitable tolerance concept, costly measurements can be avoided that are used to prevent the alignment errors of the test specimen. As a result, a mathematical model concerning the torsion would be created and the tolerance chains shall be investigated and solutions for both problems could be searched.