Design And Analysis On General Project And Key Parts Of Low-speed Wind Tunnel Strain-gauge Balance Static Calibration System

Wind tunnel strain-gauge balance is the core measuring device in the aerodynamic force-measuring test of aircraft in the wind tunnels. Static calibration equipment is a special standard metering device for strain-gauge balance calibration. The performance of static calibration equipment would effects the performance of balance, and the performance of the balance would effects the tests results on accuracy.This thesis presents the research on general project and key technical links of low-speed wind tunnel automatic strain gauge balance static calibration system. The execution project and development are also presented. The system consists of automatic weight loading system, six-degrees-of-freedom parallel resetting system, attitude and displacement measurement system, data acquisition system, central control system, data processing system and auxiliary devices.The main works discussed in this thesis includes the following:The first, research and design on the general project. According to the analyzation of some advanced calibration equipment at home and abroad, and based on specific situation of project, the overall technical route and work principle are laid out, the analysis of factors influencing system accuracy is also presented.The second, research and design on loading system. According to the analyzation of specific factors and rule of the effect, the key parameters of loading system are determined, a new automatic weight loading project is provided. The weight loading project has advantages of both series weights and combined weights, has the good adaptability of weight, different design load balance just need single weights assembly, which avoid inverse operating caused by repeat weights assembly and dull loading work.The third, research and design on automatic resetting system. The primary design calculation of six-degrees-of-freedom parallel resetting system is exposited.The paper present the attitude and displacement measurement principle of Loading device based on multi-CCD Array camera. The feasibility, measuring accuracy, factors influencing accuracy and countermeasures are also expounded. The six-degrees-of-freedom parallel resetting system has higher limit of load capacity, simple structure and resetting precision guaranteed. The attitude and displacement measurement system of Loading device based on multi-CCD Array camera has simple structure, convenience to measurement ,easy to be refit and maintained, easy to meet the requirement of precision.Compare to the calibration system at home and abroad, and the performance of this equipment already reached the international advanced level. It is essential for improving aerodynamic force-measuring test results accuracy, developing of aircraft in military, civil areas and high technology strategy weaponry.