Design and Calibration of a Large-Sized and High-Stiffness Wind Tunnel Test Dynamometer Composed of Dual Multipoint Distributed Force-Measuring Units

Wind tunnel tests are crucial for evaluating aerospace vehicle performance during development. However, existing force measurement systems struggle with large-scale, high-load test models. This study proposes a large, high-stiffness wind tunnel dynamometer using dual multipoint distributed force-measurement units. A mechanical model based on point-support theory was established to derive input-output force/torque relationships, enabling calculation of structural dimensions and sensor ranges. A 3-D simulation model validated the system’s structural strength through static analysis. Independent calibration of each unit ensured reliable force measurement, reducing errors. A custom six-dimensional calibration device was designed, verified via finite element analysis, and used for unidirectional force calibration and dynamic testing. The dynamometer achieved static performance meeting design specifications (linearity error ≤0.3% for forces, ≤0.6% for torques; repeatability error ≤1% ), with a maximum linearity error of 0.335% . Decoupling compensation further enhanced six-dimensional force/torque measurement accuracies to 0.086% –1.627%, demonstrating up to 92.65% improvement. Experiments confirmed the model’s theoretical validity, simulation accuracy, and applicability to large-scale, high-load, and high-frequency scenarios. This solution addresses critical gaps in modern wind tunnel testing for large aircraft models.