Dragos Laurentiu Popa

Studies about Movement Biofidelity of a Dummy Neck Used in an Impact Testing Device

The paper presents the studies made on a similar biomechanical system composed by neck, head and thorax bones. The main movements analyzed were: axial rotation (left-right), lateral bending (left-right) and flexion-extension movement. After simulation was obtained the entire mechanical behavior based on data tables or diagrams. The models were defined in a CAD environment which includes Adams algorithm for dynamic simulations. The virtual models were obtained starting with CT images made on a living human subject. That virtual model composed by neck and head can be included in complex system (as a car system) and supposed to impact simulations (virtual crash tests). Also was developed a mathematical model based on Lagrange equations for a frontal impact testing cervical system. Our research team built main components of a testing device for dummy car crash neck-head system using anatomical data.

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.

Experimental Bench Used to Test Human Elbow Endoprosthesis

In this paper, the 3D virtual model and the prototype of an experimental bench designed and used to test endoprosthesis prototypes for elbow joint in flexion-extension and pronation-supination movements are presented. The experimental tests were carried out on a group of nine healthy subjects and on the corpse prosthetic elbow. Experimental data for flexion-extension movement cycles were acquired using SimiMotion video system. The data files and the flexion-extension angle diagrams are obtained for all the subjects and for the corpse prosthetic elbow. The command programs in C++ for the performance of experimental tests on the bench are elaborated. A comparative experimental study of flexion-extension movement for healthy elbows and for the prosthetic corpse elbow joint fixed on the experimental bench is presented.

The Behavior of the Virtual Human Head-Neck System during the Main Movements

The subject of this paper permits the cooperation between many researchers which activate in different fields, which have the capacity to develop informational methods and technologies to solve difficult problems given by the complexity of the scientifically target. Using computer-aided design (CAD) and dynamic simulation programs was developed a virtual model of the cervical human spine that includes the main muscle groups simulated by springs with dynamic parameters, nonlinear and variable. Were studied the main types of movements (displacements) lateral bending (left-right) and flexion-extension movements.

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).

Design and Finite Element Analysis of a New Spherical Prosthesis-Elbow Joint Assembly

This study aims to present a new virtual model of an elbow prosthesis with as few components as possible, having a simpler technological approach which can be an important base for the study of the complex behavior of the elbow joint. The prosthetic system is of spherical type consisting of three parts: a part implanted in the humerus, a part implanted in the ulna bone and a third part transforms the assembly from an unconstrained prosthesis in a semi-constrained prosthesis. The kinematic simulation of the flexion-extension and pronation-supination movements of the spherical prosthesis—joint assembly was performed. The virtual model is designed in Solid Works software. By using the finite element method, the healthy elbow joint and the prosthetic elbow joint assembly were analysed and the comparative diagrams of the maximum stress in healthy elbow joint and in prosthetic elbow joint concerning the flexion-extension and pronation-supination movements were drawn and analysed.

3D Model Based Process in Automotive Industry

The three dimensional design of modern auto vehicle through advanced virtual engineering methods is used from early development processes. From over 10 years automotive manufacturers’ have used 3D-CAD software packages following conventional development strategies of the product. These tools offer the possibility to design components through digital mock-up processes reducing time and errors in production. In this paper we evaluate the evolution of 3D-CAD based development processes based on geometry generation, conceptual design and simulations tools. The DMU method allows importing the 2D sketch in 3D software then creates a virtual model which can be optimized and analyzed.

3D Skull Virtual Model, Based on CT or MRI Images, Used for Dentistry Simulations

In order, to understand the problems, which occur during the dentistry simulations, it was highly important to be acquainted with the anatomy of the human skull skeleton, the way these bone components are working together to achieve a normal functionality. In this respect CAD parametric software has been used as it allows to define models with a high degree of difficulty. First, the main bone components were defined by using CT images. These images were then transferred to a CAD software using different methods and techniques. These models were completed in SolidWorks where, step by step, the virtual model of the studied bone system has been defined. Using the direct measurement method on some skull components the virtual bone base elements were generated. Then, the virtual models were exported to a software for FEA simulation and prepared for every dentistry simulations. These models were tested and was generated the finite elements structure. In the end of the paper, were extracted interesting conclusions.

Virtual Model and Simulation of the Normal and Affected Human Hip Joint

To generate a virtual human hip is a main goal for our research team. Also, starting from the normal virtual hip joint and using the important orthopedics information was defined the affected hip joint. All these models were generated in a 3D virtual environment starting with CT scanning images. Using an original method all the scanned CT images were re-defined and re-drawn and transferred to the 3D software. The resulted curves were used to generate the bones and the virtual complex system of both hip joints. With motion and geometric constrains the bio-mechanical assemblies were defined, starting from anatomical information. The normal hip joint and the model of the affected hip were defined and exported to ANSYS, software based on Finite element analysis.

Simulation of a Mono Cylindrical Engine with LES Software

This paper analyzes the numerical research carried out on a single-cylinder research engine. 1D engine simulation tools are widely used to model the combustion and gas flow processes in a four-stroke spark ignited engine. LES software represents a powerful tool for optimization of engine dynamic processes and parameters. The simulation and design of engines can drastically reduce time and costs in automotive industry. 1D advance systems are needed for an effective boosting of the engine. A mono cylindrical spark ignition engine was analyzed to determine the performance and general parameters.