Design And Prototype Fabrication Of Repeatably Deployable Umbrella-type Antenna For Cube Sat

Deployable antenna is an indispensable space equipment in space engineering.In order to meet the needs of high gain and high band of satellite-borne antenna,umbrella-type deployable antennas have an irreplaceable position because of high stow and high precision.In order to realize the deep space exploration of Cubesat,the demand of carrying deployable antenna in the CubeSat arises.It is of great significance to improve the reliability of deployable antenna for realize the repeated deployment and closure in the harsh space of Cubesat.The purpose of this thesis is to design an umbrella-type antenna applied to a CubeSat,and carry out kinematics analysis,error analysis and prototype fabrication.The specific work is as follows:1.Taking the 0.5 meter Ka-band small umbrella-type antenna as the research object,a retractable deployable mechanism of the umbrella-type antenna was put forward,and the repeated deployments of root ribs,tip ribs,and subreflector were realized.The three-dimensional solid model of the antenna reflector and the deployment mechanism was established to verify the feasibility of the deployment scheme.Kinematics analysis was carried out during antenna deploying process,and models of position,velocity and acceleration were established.Through input-output model,linear programming was proposed for angular velocity of root rib and tip rib during antenna deploying process,and stable deployment was realized on the basis of repeatable deploying and retracting.2.On the basis of the theory of effective length model and the general analysis model of mechanism motion error,the calculation model of single degree of freedom linkage mechanism that considering size error and hinge clearance error was established.The error curve of antenna rib vertex under different clearance during antenna deploying process was completed.On the basis of First Order Second Moment method,the change curve of the reliability was got and the results showed that the errors of the apex of the root rib and the tip rib during antenna expansion were within the acceptable range.3.A 0.5m Ka-band umbrella-type deployable antenna model was made.Completing the selection of the control motor and settings of motor driver,editor.Under the drive of a stepping motor,the deploy and undeploy of antenna prototype and the measurement of surface precision were tested.The repeatable performance of the umbrella antenna was verified.In this thesis,a CubeSat umbrella-type antenna which can realize repeated deploying and stowing was designed.The operation analysis and error analysis of the deploying process were carried out and the error variation of the deploying process was within the allowable range.The test of deploy and stow process and the measurement of surface precision were realized,the results show that it is feasible in engineering practice.This thesis has some engineering application value for the further study of the deployable antenna of CubeSat.