Design And Analysis Of Double-loop Truss Deployable Antennas

With the development of space technology,space structure is increasing the size of the structure.It offered more new requirements than before.To improve stiffness and strength of the deployable antenna,at the same time it demanded the total weight and volume of the antenna does not increase proportionally with the increase of the antenna aperture.This paper presents a double circular truss deployable antenna with hexahedral element.Then,the analysis and improved design is processed.And double ring truss deployable antenna of 4.2m diameter is manufactured.Double ring truss deployable antenna with hexahedral element,the main advantage is that the structural stiffness to meet the requirements of large aperture.The total weight is not in proportion to the increase with the antenna diameter increases.Deployable truss structure existed a class of over constrains,the number of bars are more complex geometric topology.Based on the theory program of generalized inverse,symbolic matrix is introduced to judge the deployable of the structure.The results showed that when generalized inverse theory and the introduction of the symbol matrix,making the solution accuracy and solution speed has definitely improved.The design method does not require human intervention,programs can be achieved.For the deployable double-ring truss antenna with hexahedral element,scale-model analysis is required for the full-scale model of the relevant characteristics.In this paper,similarity relationship between of the model and the prototype is researched.The property of driving force and the structural natural frequency are analysis.The similarity formula of driving force and the structural natural frequency is derivedDynamic analysis is an important part for large aperture deployable antenna.Multi-body dynamics analysis software(ADAMS)is adopted to process the simulation.First,the geometric solid of large aperture truss deployable antenna is modeled.Then,synchronized gear joint,rotating-pair,sleeve,fixed pair and other constraints is accounted.User subroutine is introduced for simulation.The node displacement,velocity,acceleration and pull forces generated on the node,etc.are calculated.It offers useful guidance for the manufacture and optimization design of the large aperture antenna.This paper studies two-ring truss deployable antenna with hexahedral element.It combined the properties both structure and mechanisms,mainly,mechanisms motion of the launched in orbit state,the structure characters in working condition.To ensure the structural safety and reliable deployment,it primarily demands high intensity,the joint flexibility,synchronization gear restrictions,high strength of bar,feeble friction.In aspect of the mechanical design,some optimization design has been put forward.Specially,integrity node,synchronous gear,restrict equipment of full deployment,driven style and disposal of the wheel gear have been put into practice.Take account of relevant technical indicators,double ring truss deployable antenna of 4.2m diameter have been manufactured.Experiments show that double ring truss deployable antenna can deployed smoothly driven by the motor.