Real-time monitoring method of global displacement for aircraft tooling positioner based on sparse displacement measurement

The aircraft tooling positioner serves as the reference for positioning during aircraft component assembly, and its global displacement state directly affects assembly accuracy. Thus, it is critical to monitor the global displacement state of the positioner in real-time to ensure efficient and accurate assembly. In this study, a real-time reconstruction method for the global displacement state of aircraft tooling positioner based on sparse point displacement measurement is proposed. Using only four displacement measurement points within a narrow and nearly enclosed space, high-precision online monitoring of the global displacement state of the positioner can be achieved. Firstly, based on the principle of modal superposition the real-time reconstruction model of the global displacement state of the positioner is established. Then, an optimization method for the layout of displacement measurement points is proposed by analyzing the error sources of the reconstruction model and the measurement conditions of the assembly site, improving the reconstruction accuracy of the model under sparse measurement point input conditions. Finally, numerical simulation and experimental verification are carried out to verify the effectiveness of the proposed method. The experimental results show that the maximum reconstruction error of the proposed method is better than 0.0548mm, and the reconstruction time is better than 0.02s, satisfying the real-time monitoring requirements of the global displacement state of tooling positioner in large aircraft assembly.