Research On Vibration Of Wire-driven Parallel Robot As Model Support In Wind Tunnel

As a new type of model support technology in wind tunnel test,the WDPR(Wire-driven Parallel Robot)support has the advantages of small aerodynamic interference,large support stiffness and good dynamic characteristics.However,in the wind tunnel test,due to the flexibility of the wire,the vibration of WDPR support has attracted much attention,but the research on the vibration of WDPR support is very rare at present.In this paper,the vibration characteristics of WDPR support are studied theoretically and experimentally,and valuable research results are obtained.According to Newton-Euler method,the kinematics and dynamics model of WDPR-8 is established.Then,the modal properties of WDPR-8 are analyzed theoretically,and the modal experiment is carried out by means of hammer method.The foundation for the subsequent research on the vibration of the WDPR is build up.The wire damping measurement method is proposed,and the experimental device is designed to solve the difficulty of wire damping measurement.The wire damping ratio under different parameters is obtained through experiments.The dynamic characteristics of the WDPR with wire damping are analyzed.The criterion of the influence of wire damping on the dynamic characteristics of WDPR-8 is obtained.The disturbance to flow field and the vortex-induced vibration of the wires are analyzed.Based on Euler motion equation of continuous medium,the transverse vibration equation of an axially moving wire is established.The parametric vibration of a single wire is studied.The conditions of wire resonance are obtained.This research provides an important theoretical basis for the study on coupled vibration of the WDPR.Considering the six-degree-of-freedom motion of the aircraft model,the parametric vibration of the static and axially moving wires,and the coupling between the aircraft model and the wires,the nonlinear coupled vibration equation of the WDPR is established.By comparing the results of coupled and uncoupled vibration,the necessity of considering coupling effect is revealed.Considering the oscillating motion of aircraft model and the axial motion of wires,the coupled vibration of the WDPR is analyzed,and the nonlinear vibration characteristics of the WDPR are revealed.WDPR-8 prototype is installed in the wind tunnel for static and dynamic tests.Real-time measurement is carried out by using position and wire tension measurement subsystem.The experimental data of aircraft model attitude and wire tension are obtained.The simulation results are compared with the experimental results to verify the effectiveness of the proposed coupled vibration model of the WDPR.This research builds a theoretical and experimental basis for vibration analysis of the WDPR support in wind tunnel tests,proposes an effective analysis method for the design and optimization of the WDPR,and provides a theoretical reference for exploring the engineering application of the WDPR.