Development of an autonomous experimental system to identify BLISK mistuning

The one-piece assembly of bladed disks, named blade integrated disks (blisks), leads to more severe mistuning effects and reduced damping. An accurate mistuning identification methodology is thus necessary for the manufacturers to avoid potential engine failure. This paper proposes a complete autonomous system to identify mistuning in the shortest possible time, with reduced human interventions and with improved accuracy. The Inverse Component Mode Mistuning method is implemented, and the mistuning pattern is
immediately determined after the experimental measurements are completed. For this purpose, the blisk is fixed on an electrodynamic shaker and the vibration measurements are performed thanks to an infrared Laser Doppler Vibrometer attached to a robotic arm. The use of a robotic measurement system offers multiple possibilities unthinkable when performed manually: 3D measurements are achievable, the positioning is made very accurate and reproducible, and many points can be measured rapidly and without human operation. A comparative study of the experimental measurements made possible with the test rig proposed is carried out.