Research Of Large 3D Deployable Truss Mechanism For Space Solar Power Station

With the increasingly harsh energy conditions,the development of space solar power plant technology has important strategic significance.However,its main structure has a diameter of 23 m.Due to the limitation of the current transport capacity of the launch vehicle,it is urgent to develop a three-dimensional deployable truss mechanism as the main structure of the space solar power station.In this paper,a truss mechanism with large folding ratio and large diameter was proposed,and the basic characteristics of the basic unit for constructing the deployable truss are analyzed.Its driving mode and kinematics are analyzed.The equivalent beam model of the truss was established and used to optimize the truss parameters.Finally,the prototype of the deployable truss was developed and the experimental verification and results analysis were carried out.Firstly,according to the research results and the truss design requirements,the basic components of the expandable truss are designed according to the existing deployable mechanism configuration,and then the basic characteristics are analyzed.Then,deployable truss is constructed by the axial array,and the number of configuration edge is optimized by multi-parameter comparative analysis,and the truss configuration is determined according to the optimization results.The space deployable truss has a function of unfolding.On the basis of determining the deployable truss type and folding principle,the kinetic characteristics of the truss mechanism are analyzed to ensure that the truss scheme is reasonable and feasible.The position of the drive point of the deployable truss is designed and the rationality of the scheme is analyzed.The feasibility of the drive is verified by ADAMS simulation.The D-H coordinate system of the basic unit of the deployable truss is established.The spatial motion trajectory of the key joints and other kinematic parameters are obtained through calculation.The holistic model of the deployable truss is established by ADAMS,and the correctness of the kinematics analysis of the configuration is verified by simulation analysis.Based on the principle of energy reciprocity,the dynamic analysis of the deployable truss is carried out,the equivalent model of the continuous beam of the truss structure is established,and the equivalent mass matrix and equivalent stiffness matrix of the equivalent beam model are derived.Based on the undamped vibration equation,the influence relationship between the truss parameters and the fundamental frequency is established by the equivalent model.The influence of the detailed parameters of the deployable truss structure on the fundamental frequency and the optimal calculation of the structural parameters are carried out.The detailed structural parameters of the expandable truss are given based on the detailed design of the preferably completed deployable truss structure.The prototype of the deployable truss is developed,and the achievability of the unfolding function of the truss prototype and the rationality of the drive layout scheme are verified by the prototype experiment.The correctness of the equivalent model is verified by the static stiffness test and the modal experimental results of the prototype compared with the theoretical calculation results.The above analysis and experiments provide design ideas,theory and data support for the later truss design.