Mihaela Liana Bogdan

About Education in the Engineering Graphics in the Technical Universities from Romania in Concordance with Bologna Model

The necessity of technical education structure and content in the organization system on three cycles conform to Bologna model must be taken in concordance with Engineering occupation in the goods production, services, research-development and education in Romania. The general necessities are particularized for education in the Engineering Graphics from technical education from Romania.

Mathematic Model for Analysing the Dynamic Behavior of a Vehicle in the Field of Chaotic Movements

This paper presents a plane equivalent model of the vehicle and its mathematical model attached. The mathematical model is under a form of four differential equations system of order 1, in order to analyze the dynamic behaviour of the vehicle movement. Its goal is to determine the ranges of speed for that movement is stable or is unstable, or having chaotic character. The authors consider being necessary to know the conditions in which movements occur chaotic movements to avoid them through constructive or functional limitations. Speed values are identified for the behaviour of the system is placed in the quasiperiodic movements field or exceeding these movements trough chaos and are highlighted by the specific instruments: the trajectories in the phase plane, Poincare section and power spectra.

Human Head-Neck System Behavior during Virtual Impact Automotive Simulations

The paper presents the studies made on a similar biomechanical system composed by neck, head and dummy body components. The models were defined in a CAD environment which includes Adams algorithm for dynamic simulations. After simulation was obtained the entire mechanical behavior based on data tables or diagrams. That virtual model composed by neck and head was included in complex system (as a car system) and supposed to impact simulations (virtual crash tests). This paper presents issues concerning the use of CAD systems in modern technology virtual prototyping, in this case a complex virtual model for a car system used for impact simulations. Virtual prototyping is a process that uses a virtual prototype instead of the physical prototype for testing and evaluating specific elements of the designed product. Virtual prototype is created on the computer closer to the actual characteristics and operating conditions so as to allow the simulation to perform the role for which it was designed. The three-dimensional model has been exported into simulation software able to perform kinematics simulations and finite element analysis, at the same time. With that virtual model were analysed different situations similar with car crash. Results of simulations have been analysed and can be compared with measurements made on the experimental device (under construction).

Analysis of the Commercial Speed of a Public Passenger Transport Line from Craiova-Romania

This paper presents the analysis and the way of determining the commercial speed for a public transport route (a line) of people from Craiova. Calculate the optimal distance between the stations on the route under consideration, which will ensure a minimum journey time for the passengers. Commercial speed was determined according to the length of the route and its time, which depends on the number of stations, the passenger flow and traffic conditions specific to Craiova.

Analysis about Influence of the Mechanical Vibrations on the Function of Shaping-Machine

In this paper, it is analyzed the effect of shocks on the kinematical parameters, linear and angular courses and accelerations, of shaping-mechanism at the function with shocks. In this scope, with experimentally recorded data it is plotted the diagram of variation (in time) of mentioned parameters obtained for the different regimes of processing for the component elements of the shaping mechanism in the case of function with shocks. It is made a comparative analysis of the laws of variation for kinematical parameters obtained for the different regimes with shocks in the conditions imposed, resulting, finally, the effect of shocks.

The Simulation of the Vehicle Motion Based on Generalized Mathematical Model of Vehicle Motion

The paper presents a numerical simulation of the motion of a car based on a mathematical model that takes into account the lateral and longitudinal forces from the contact stain, forces given by suspension system, aero-dynamical force and weight force. In the paper is also presented the mechanical model for a vehicle upon which it was built a mathematical model. Considering the mechanical model and the mathematical model vehicle dynamics numerical simulations were made using the computing environment Matlab. Numerical simulations presented in this paper are obtained at relatively constant speeds of the car, taking into consideration a sinusoidal variation of the steering angle of the wheel: the variation of steering angle was with amplitude equal to 5° and period equal to 3 s. The results refers to the linear and angular movement and velocity, linear and angular accelerations, deformations of the tires, lateral forces.

The Modal Analysis for the Helicoidally Spring of the Macpherson Automotive Suspension

The paper presents a modal analysis for the helicoidally spring from the compound of the Macpherson automotive suspension. In the first part, it is described the device used for the experimental study and then, the measurement equipment used, too. First of all, it is represented the kinematical scheme and 3D representation for the device mechanism included the helicoidally spring necessary to the dynamic analysis. After this, are made some measurements of different parameters of the helicoidally spring obtaining the experimental values which are compared finally with the simulation results.

Modeling and Simulation of the Stand for Testing of Helicoidally Springs from Automotive’s Suspension

In this paper is made a tridimensional model for the stand use for the testing of helicoidally springs from automotives suspension using Solid Works soft. Then, it is realized the simulation for the testing of helicoidally springs. On this 3D-model is realized a dynamic analysis for the stand for obtaining the variation of stresses and deformation for all parts of this stand.

The Method of Design and Manufacturing of the Gear Hobbing Cutter with Bulges

This paper presents the design and manufacturing aspects of these tools. Constructive and geometric peculiarities are exposed for the gear hobbing cutter with large modules. The design of the gear hobbing cutter with modified profile in the parametrized variant permits a rapid adaptation to any conditions. Depending on the particular constructive geometric of the gear hobbing cutter profile it was created the virtual prototype (solid model). This is analyzed and, in the final stage, it is manufactured [1,2,3,4,] . Manufacturing techniques of the tool include the obtaining of the profiled knifes for clearance (achieved by increased 50:1 templates on the machine for profiled tools) and the special control templates (obtained on templates milling machine F. Studer) [. This paper presents the method of obtaining of the gear hobbing cutter profile by adjusting the corresponding shape of the abrasive disc to optimize the grinding conditions [. It is recomended the method which use the changing of the rack reference imposed by technical and functional conditions [7,8,.