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The stability of thin plate plays an important role in the design and strength check of ship structure. In order to study the shear stability of ship’s thin plates, in-plane shear buckling tests were carried out using a picture frame fixture and a 3D full-field strain measurement system. The critical buckling load, full-field displacement/strain information, and load-displacement curve were obtained. The finite element model with the frame fixture was established based on ABAQUS, with the eigenvalue buckling analysis and nonlinear buckling analysis being carried out to obtain the mechanical response information of the buckling and post-buckling of the ship’s thin plate. The effectiveness and accuracy of the numerical simulation method are verified by comparing the numerical simulation with the experimental results. On this basis, the critical buckling load obtained by shear test, numerical simulation, and theoretical calculation is analyzed, and the function of the frame shear fixture and its influence on the critical buckling load are defined. The research in this paper provides a useful reference for the testing and simulation of in-plane shear stability of ship’s thin plates.

Cable-driven parallel robot is a special kind of robot, which is actuated by cables. It is already applied in the low speed wind tunnel to get aerodynamic measurement of aircraft model, and the aircraft pose could be adjusted by changing the cable length. Whether it can be used in hypersonic wind tunnel still needs further discussion. This paper presents the dynamics and aerodynamics analysis of a large-scale model supported by 6-DOF cable-driven parallel robot to investigate the feasibility of this special kind of suspension system in hypersonic wind tunnel. The description of this setup with a X-51A-like model is given, and then based on the system dynamic equations, aerodynamic force and stiffness matrix are derived. In the simulation, properties of dynamics and aerodynamics are mainly concerned. A typical shock tunnel with flow duration of about 100 milliseconds is taken as an example, and results show that the system is stable enough to meet the fundamental static wind tunnel test. From the cable tension variation under impact load and the sensitivity analysis, it is likely accessible to derive the aerodynamic forces. Compared with the sting suspension method, cable-driven parallel robot has the priority of higher inherent frequency and more flexible degrees. The interference to the flow field induced by cables is also preliminarily proved to be small by the CFD simulation, which can be acceptable and corrected. Researches conducted show the feasibility of cable-driven parallel robot’s application in hypersonic wind tunnel.

A cable-driven parallel suspension mechanism for helicopter model in formation flight in wind tunnel test is designed and analyzed in this paper. Based on the working condition requirements of two helicopters in formation flight, a 16 cables suspension structure is designed, and the kinematic relationship of single helicopter for cooperative motion between the movable pulley suspension point and the helicopter model is established. Furthermore, based on the relative position and orientation of two helicopters, the kinematic model between two helicopters in formation flight is also established. Additionally, six degrees of freedom movement and cooperative formation flight movement can be achieved through motion control of the parallel mechanism, which verifies the feasibility of the kinematic model. The simulation results show that the parallel suspension mechanism designed in this paper has large workspace and good stability. And it can avoid interference among the cables, and between the cables and the model, which contributes to imitate the interaction of airflow among the aircrafts in formation flight and improves the effectiveness and credibility of wind tunnel test results.

A cable-suspended parallel mechanism for full rolling motion of moving platform is designed, a kinematic mathematical model and a statics model of the mechanism are established, the variation of cable length during full rolling motion at two deflection angles of 0° and 10° are analyzed, by creating a virtual prototype, the distribution of cable tension and the change of centroid displacement of the moving platform are analyzed. The research results will provide a new technical scheme for full rolling of moving platform.