Analysis of the effect of sensor mass on the modal characteristics of an ultralight wing using the finite element method

Modern trends in aviation development focus on minimizing structural mass to increase payload capacity. This tendency, particularly noticeable in light aviation and the UAV sector, complicates the conduct of ground vibration tests due to the low mass of the objects under investigation. These difficulties are associated with the need to place additional mass on the aircraft surface to obtain its modal model. This mass leads to a decrease in the accuracy of the mathematical model if it is not taken into account. The aim of the work is to investigate the effect of sensor mass on the modal characteristics of the structure (frequency and mode shape) during ground vibration tests. In the article, a calculation was performed using the finite element method on a model of an ultralight wing. Studies were conducted for 5 different cases. A comparison of the obtained results, which are presented in Tables 1 and 2, was carried out. The analysis showed a tendency for the natural frequencies of the structure to decrease and the mode shapes to shift with increasing mass. The obtained results indicate a significant influence of the additional mass on the modal characteristics. This, in turn, points to the necessity of conducting experimental studies and developing a methodology for ground vibration testing of lightweight structures to obtain the real modal characteristics of the structure.