Research On Nonlinear Behavior Of Planetary Rover Mast With Laminated Composite Materials Undergoing Attitude Adjustment Motion

Mast is a deployable mechanism for holding high-precision cameras on the planetary rover.,which has multiple degrees of freedom for flexible posture adjustment.In order to lighten the weight of the spacecraft and reduce the launching cost,the mast mechanism are mostly made of laminated composite materials,which has the characteristics of low density and high strength.However,its large flexibility and small damping characteristics make a significant coupling between the attitude adjustment movement and its own elastic deformation of the mast mechanism during the working process and the vibration and nonlinear deformation will inevitably affect the working quality of the equipment at the end of the mast mechanism.Therefore,this paper mainly focuses on the analysis of the dynamic characteristics of the planetary rover mast with laminated composite materials undergoes posture adjustment movement.The planetary rover mast is a typical spatial multi-flexible body system.The nonlinear characteristics make it difficult to analyze the dynamic behavior of the mast when performing the posture adjustment.In order to improve the accuracy of dynamic modeling,the three-order shear deformation theory is used to determinate the constitutive relation of the chain topologic planetary rover mast with the laminated composite materials in this paper.The deformation is expressed by finite element method and the nonlinear dynamic model of the planetary rover mast with laminated composite materials during posture adjustment movement is established based on the principle of virtual work.The modeling not only considers the geometric nonlinearity and laminated structure nonlinearity of the dynamic behavior of the mast,but also considers the coupling of the large-scale movement and its own deformation movement,which improves the modeling accuracy of the nonlinear dynamics of the planetary rover mast during the attitude adjustment.The attitude adjustment process of the planetary rover mast with laminated composite materials is simulated by experiment.The experimental data and theoretical data are compared and analyzed to verify the correctness of the theoretical model established in this paper and emphasize the necessity of considering rigid flexible coupling and nonlinear deformation in the theoretical model.It is shown that the model can be applied to the dynamic analysis of the attitude adjusting behavior of the planetary rover mast.On this basis,the experiment of the planetary rover mast with isotropic materials undergoing posture adjustment movement is carried out.Through the comparative analysis of the experimental data,the influence of laminated structure on the dynamic characteristics of the planetary rover mast is preliminarily verified,which provides an effective reference for vibration control of planetary rover mast undergoing posture adjustment.The simulation example analysis is carried out based on the presented model in this paper.Taking the neutral surface radius,layer angle and layer method as variables,the correctness of the theoretical model is further verified by comparison between simulation results.The geometric nonlinearity and laminated structure nonlinearity of the dynamic behavior of the planetary rover mast during the posture adjustment process are discussed,which provides a theoretical basis for the dynamic control and vibration suppression in the attitude adjustment process of the planetary rover mast and improves the working performance and image quality of the end equipment.