| Parabolic cylindrical antennas are widely used in space-based target monitoring,space remote sensing,water resources detection and other fields with unique advantages such as easy beam automatic scanning and multi-frequency signal transmission.With the continuous development of space technology,the size of the antenna structure has become an inevitable trend,but due to the limitation of the rocket carrying capacity,the traditional solid surface reflector antenna has been difficult to achieve large-scale design.As an antenna structure widely used in the field of aerospace at home and abroad,the deployable antenna has the advantages of light weight and high storage ratio,and can meet the design requirements of large and even super large spaceborne antennas.Therefore,this paper focuses on the innovative structure design and analysis of the large deployable parabolic cylindrical antenna.The main work carried out is as follows:1.A Y-shaped ribbed deployable parabolic cylindrical antenna is proposed.In this design,planar linkage mechanism and pantograph mechanism are used as the supporting structure and deployment mechanism of the antenna,and modular design is adopted,which can meet the design requirements of different sizes of antenna.Based on the detailed analysis of the deployable mechanism and basic elements of the antenna,the storage ratio,area density and other parameters of the antenna are compared with other similar parabolic cylindrical deployable antennas,which highlights the unique advantages and application potential of the scheme.2.The form-finding design of deployable parabolic cylindrical antenna cable net structure is completed.Firstly,according to the forming characteristics of parabolic cylindrical antenna reflector,the cable net configuration is designed in detail;secondly,in order to ensure that the cable net structure has enough support stiffness and surface accuracy,the pure cable net structure is designed.Finally,considering the influence of truss deformation on cable net pretension and surface accuracy,the mechanical model and optimization of cable net truss composite structure are established The model realizes the form-finding design of cable net truss composite structure,effectively improves the cable net pretension distribution,and ensures the shape accuracy of antenna cable net reflector.3.The mechanism kinematics and structural vibration characteristics of deployable parabolic cylindrical antenna are studied.Firstly,the kinematic analysis and deployment planning of the deployable mechanism of the parabolic cylindrical antenna are realized by using the multi loop motion analysis theory,and the corresponding motion law curves are given.Then,the structural vibration characteristics of the deployable parabolic cylindrical antenna are analyzed,and the influencing factors of the natural frequency of the antenna structure are preliminarily discussed,which provides guidance and guidance for the design and optimization of the antenna structure reference resources.4.The parametric modeling software of parabolic cylindrical deployable antenna is developed.In order to realize the rapid modeling of parabolic cylindrical deployable antenna,CAD software UG NX and programming software visual are used Then,the input and transfer of antenna modeling parameters are realized through the user interface and script file,which turns the tedious operation process of antenna modeling into a visual window mode and greatly shortens the modeling time and design cycle. |
