Study on Dynamic Characteristics and Parameter Influence of a Kind of Bilateral Restraint Impact Vibration System

In this paper, the hinge in the articulated structure is studied, the gap hinge is described as a nonlinear bilateral constraint, and the equivalent modeling and analysis of the hinge connection collision vibration are carried out based on the Lankarani–Nikravesh nonlinear contact force model. With the help of the method of nonlinear system dynamics analysis research, the Poincaré mapping of hinge joint collision vibration is constructed, the bifurcation diagram of the system with different parameters is solved, and the variation law of the system motion and the influence of parameters are analyzed by combining the time response diagram, phase diagram, Poincaré cross section diagram, and spectrum diagram of the typical motion of the system. The simulation results show that the system moves in a single degree of freedom and varies with parameters with multiplicative period bifurcation and rubbing edge bifurcation leading to chaos; the system’s periodic motion has shock state mutation and mirror jump transformation.

Application of 3D-printing technologies for production of master-model in engineering industry

Analysis of 3D-printing methods used in the molding production to manufacture master-models has been carried out. The technology was selected, which allowed one to make high-precision parts, combining the molding and the 3D-printing. Factors effecting on the quality of 3D-models printed by this technology were analyzed. Experimental studied for determination of the printing parameter influence (layer thickness, filling percentage, printing velocity) on ultimate strength of specimens made of ABS-plastic were carried out.

DEFORMATION AND BUCKLING ANALYSIS OF SHALLOW CONICAL SHELLS BASED ON IMPROVED MODEL OF WIND LOAD USING ENVIRONMENT ANSYS

The process of deformation and buckling of shallow thin-walled elastic conical shells has been investigated for the case of significantly non-uniform stress-strain state due to the action of wind load based on improved model of pressure application schema to the surface of shallow shell and for hinged hedge of border. An improved model of wind load was based on data presented in terms [5, 6] and was a logical continuation of previous investigation of wind action on shallow conical shells based on model of first approach [3]. Deformation and buckling process investigation has been carried out using software ANSYS which effectivity was approved by the fact of being used by NASA for its aerospace projects. A model of shallow conical shell has been made using four-corner finite element SHELL 281 with 8 nodes that let us obtain not only symmetrical relatively to the axis of rotation buckling form but an asymmetrical too. Two types of computation have been made during numerical modeling – linear bifurcation computation with determination of linear pressure qcr value and corresponding to it buckling form, and computation of geometrically non-linear problem of deformation with determination of limit pressure qlim and corresponding buckling form. Obtained buckling forms have been compared to the deformed shape of shell surface when aerodynamic computations have been carried out using software ANSYS. An estimation analysis has been made for case of application of improved model of wind load in comparison to the previous investigation according to the values of baring capacity and buckling shape coherence during resolution of static tasks and comparison to the results of aerodynamic solution. An analysis of base parameter influence has been carried out for the model of first approach and current improved model according to the bearing capacity value and local extremums on schema of pressure intensity distribution of wind load. Specific moments of deformation process computations based on improved model using environment ANSYS have been mentioned and of further analysis on the basis of improved model with it specifics have been given too.