Research On Collision Characteristics Of A Shear-warping Flexible Beam

Based on two contact collision calculation theories,this dissertation simulates the collision characteristics of rigid small ball and a shear-warped flexible beam.In the development of new,intelligent and precision machinery,the application of flexible multi-body systems has great advantages compared with traditional rigid mechanisms.In the dynamics calculation of flexible multi-body systems or rigid-flexible multi-body systems,research on the collision characteristics of flexible mechanisms is becoming more and more important.In this paper,a shear-warped flexible beam is used as the carrier,and the collision dynamics calculation model of two flexible beams is established.The collision characteristics of the flexible beam are obtained by simulation.The specific work is as follows:Firstly,aiming at the assumption that the beam cross section maintains a rigid plane under the arbitrary beam condition,a three-dimensional two-node cross-section warping flexible beam element model is proposed,and the haplotype function and its cross section are derived.The displacement vector difference theoretically proves the warpage of the cross section of the flexible beam.Secondly,based on the Hertz contact theory,the Hunt-Crossley continuous contact force model is selected,and the collision model of the three-dimensional two-node warped flexible beam is established,and it is substituted into the dynamic equation of the warped flexible beam to obtain the collision process.The law of the collision force with the mutual embedding amount of the two collision objects,the curve of the collision force with time,and the warpage deformation law of the cross section of the flexible beam under the impact force,and the cross-section deformation of the low-order beam model under the same conditions Compare.Finally,the rigid coordinate ball is modeled by the natural coordinate method.The flexible beam is modeled by the absolute joint coordinate method.The rigid-flexible collision constraint model is established.The deformation and the whole process of the flexible beam with the rigid ball motion during the collision process are simulated.The collision force in the medium and the strain change law at a specific point are compared and analyzed.The difference between the two methods of collision solving is analyzed.The analysis shows that the Hunt-Crossley contact force method can be used as a valid method for quickly estimating the collision force at the collision point when solving the collision problem.Method,collision constraint method is an accurate method for solving collision dynamics problems.