Wire-driven parallel robot suspension system for SDM in a low-speed wind tunnel

Abstract

A wire-driven parallel robot with eight wires (WDPR-8) acting as the suspension system for an aircraft model in a low-speed wind tunnel is introduced in this paper. A kinematics model for WDPR-8 is established here. A theoretical basis is also provided, through which movement control of the model is achieved by changing the wire length. A model motion control subsystem, a monocular vision measurement subsystem for the model position, and a data acquisition subsystem were also developed for WDPR-8. A prototype of WDPR-8 was built and mounted in a low-speed wind tunnel with an open test section. A six-component strain-gauge balance was installed inside the test model to acquire aerodynamic parameters. The aerodynamic coefficients of the static test show reasonable agreement with reference results. The difference between the test result of WDPR-8 and the results from reference is smaller in the positive angle of attack than the negative angle of attack, and the total difference between WDPR-8 and other facilities is under 10%. Pitch dynamic tests with different amplitudes and frequencies were used to verify the aerodynamic hysteresis phenomena. The research indicates it is successful that the solution of measuring aerodynamic parameters with strain-gauge balance set into the standard dynamic model suspended by WDPR. It demonstrates that WDPR-8 is effective and feasible as a model suspension system in a low-speed wind tunnel. Furthermore, test results without interference correction in accordance with the reference data proves that the interference of Wire-Driven support system to flow field during wind tunnel tests is negligible. Finally, WDPR suspension system introduced in this paper will remarkably improve the efficiency and accuracy in wind tunnel test.