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This research addresses attention to human upper limb experimental analysis during feeding process aiding disabled persons. The research core is focused on the experimental process of obtaining the angular amplitudes and trajectories developed by the human upper arm during feeding process. The research originality consists on the obtained results which can be used in further researches for command and control of robotic assisting devices.

In order to control the temperature during milling process of aluminum alloys and keeping as minimum as possible, the choice of the cutting parameters and their optimization is very important, both for the tool wear but also for the surface quality of machined surface. The main purpose of this paper is to find the optimum values of the milling parameters (rotational speed and depth of cut) so that the minimum value for the temperature to be obtained. Using adequate experimental conditions with contact measurements techniques (thermocouple K-type) carried out on the some types of aluminum alloys and the appropriate statistical instruments, the most influencing cutting parameters and their values on the cutting temperature can be found. The results are presented both analytical and graphical.

The paper presents an analysis at a molding process for a twin button mouse. There are analyzed few variants for a single nest and for a four nests mold, using different gate positions. There are emphasized the quality parameters for the molding processes, and finally a cost estimation is done, which allow to select the most convenient solution.

According to recent research, quite a large part of the buses have exceeded the loading standards, which causes road damage. In order to reduce weight, the use of lighter materials such as aluminum was used. Moreover, the cost of maintenance decreases and the fuel consumption is reduced. In this paper we summarize the study of the dynamic and vibrational behavior of the chassis, including the rolling system. In the paper [2], several models have been elaborated necessary for this study. In the present paper we proposed the integration and, implicitly, the finding of the dynamic response, as a result of the behavior of the chassis in operation, in the form of time functions that we represented graphically according to a real numerical application, these representations better suggesting this behavior.

The paper presents an analysis of a molding process and the structure of the mold for a joystick handler. At the simulation of the molding process are analyzed multiple variants changing the number and position of the gates, the runner system, and the number of the pockets. Several combinations of technological parameters are taking into account in establishing the set of variables, which gives the best quality for the part. With the aid of Autodesk Inventor and Moldflow software, a complete set of quality parameters are predicted.

In this paper, we examine two types of Dammar-based bio resins. In the first type, Dammar alone is used as natural resin, while in the second type a mixture of 70% Dammar and 30% Sandarac is used. Three sample sets were made of each of these resins with a bio resin volume proportion of 55, 65 and 75% respectively, the rest being epoxy resin (used, together with the associated reinforcing material, to generate a quick polymerization process). A SEM analysis is carried out and the surface roughness of each of the studied materials. A series of mechanical properties, determined by tensile testing, are presented. We have determined the characteristic curves, tensile strength and modulus of elasticity and the influence of the epoxy resin volume proportion on the mechanical behaviour of bio resins.

For the optimum setup of an industrial manufacturing process, it can be important to know the drilling forces and moments. In many cases, theoretical estimates are not accurate enough, especially when dealing with new materials, and experimental measurements are mandatory. This paper presents the design of a dynamometer comprising a one-spoked wheel elastic component to measure the drilling thrust force and the drilling moment. A finite element analysis was made, using Ansys software, to find the most favorable position for the strain gauges. One set of strain gauges was bonded to spokes to determine the torque, and a second set was bonded to the other two spokes to quantify the axial thrust force. After dynamometer manufacturing, a calibration operation is achieved, and tests are performed by measuring the drilling forces, thrust, and torque on American Iron and Steel Institute (AISI) 1020 steel. The analogue signals from the gauges were recorded using a computer with a data acquisition device. Tool wear is studied, and the results are presented in the paper. A good agreement between results from the literature and computations demonstrates the efficiency and accuracy of this measuring instrument.

In this paper, we present a new exoskeleton robot model designed to assist human locomotion. In the first part of the paper are presented results concerning human gait motion analysis. The human gait experimental analysis is performed with goniometers sensors. In the second part of the paper are presented some structural solutions for exoskeleton robots, presented by first author in other published papers. Based on these achievements, new exoskeleton robot designs are proposed. The kinematic structure of the new robot is presented. The designed robot assures motion assistance for all the leg joints, and it is actuated with one drive. Based on this kinematic structure, the robot is modeled in the CAD design environment, SolidWorks, and the motion simulation is performed in the MSC.ADAMS simulation environment. The graphs of variation of the kinematic and dynamic parameters of the robot are presented. The exoskeleton motion results are compared with those from the human normal gait.

This research addresses to a method for 3D modeling of human bone structures. Human bones are characterized by a high level of geometrical complexity, thus the research objective is to obtain virtual bony models for analyzing them with proper engineering software. The proposed method is a derivative from a Marching Cubes algorithm and combines classical procedures with modern 3D modeling techniques and software. Through this method it is presented, as an example, the human lower limb 3D bony models developed mostly with CATIA software.

This paper addresses a knee orthotic system design used on a 4-year-old child with locomotion problems. This knee orthotic system design was made by performing a dynamic analysis of the proposed child locomotion system. The aim of this dynamic analysis was to obtain knee joint connection forces in case of a walking activity. For the proposed dynamic model, input data such as hip, knee and ankle joint motion laws were considered. These were obtained through an experimental analysis with a high-speed video camera equipment on a healthy child. Thus, a database was created, which was used as input data for numerical simulations made in a dynamic mode with MSC Adams. Through these numerical simulations, important results were obtained, and these will further validate the proposed prototype.

In this paper the design, experimental and numerical simulation of a test rig for stabilizer bars fatigue resistance study is presented. A virtual CAD of the test rig is developed, for design and simulation purposes. A dynamic simulation model is developed in ADAMS software, to study the stabilizer bar durability. Strain gauge transducers are used to measure the deformations of the stabilizer bar.

In this paper experimental investigations concerning the prototype validation of an exoskeleton for human gait rehabilitation are presented. The proposed exoskeleton is intended for human legs motion assistance, being a low cost solution. The exoskeleton provides motion assistance for human hip and knee joint. The experimental gait analysis of the exoskeleton and assisted human subject is performed with goniometers sensors. These sensors are attached to the exoskeleton hip and knee joints and measure the angle variation. The results obtained for the exoskeleton motion are compared with those obtained in case of a healthy human subject. Angular variation corresponding to a step, as a comparison for human and exoskeleton joints is performed. The conclusion is that the designed exoskeleton is proper for human gait motion assistance, because the joints motion is comparable with the human subject.

In this paper orthogonal turning processes are analyzed for different depth of cut. The temperature during the machining is analyzed. The nonlinear dynamics of the orthogonal turning are characterized with fft, phase plane, time delay, embedding dimension and largest Lyapunov exponents. The Lyapunov exponents can be used as a dynamic stability index for the system. The largest Lyapunov exponents for two different depth of cut show the chaotic behavior of the system.

In this paper some results concerning the cutting temperature and surface roughness using different milling conditions (tool material, cutting speed, speed feed and depth of cut) are presented.

In this paper were presented the main steps for defining a virtual prosthetic hip. The elements of the classic hip prosthesis were generated, one by one, using direct measurement method. These elements were included in the biomechanical hip system. The entire model was divided in finite elements. Starting from this 3D model, the goal of the research is to determine new geometries and optimized solutions for an innovative hip prosthesis.

The paper presents a method which combines experimental and theoretical approach, to derive an expression for estimating the power of thermal source in a turning process. This method uses a finite element mesh overlapped on infrared images (obtained from the cutting process), in order to extract the nodal temperatures corresponding on. A reverse formulation for a finite element analysis is used, knowing the nodal temperatures and boundary conditions, and deriving the thermal load which produces the measured thermal distribution. This experiment has concentrated to allied steel.

The present paper aims to identify the dynamic feedback of a steering mechanism in a vehicle, mainly under stationary conditions. The modal – dynamic analysis was established by applying two methods, the experimental method and the finite element modelling. For the experimental results concerning the proper frequencies of the steering box and of the tie rods assembly, a method of excitation with a measured and controlled linear momentum (impulse) force was implemented. The modal-based analysis aimed to measure the proper frequencies and the proper vibration modes. Therefore, the harmonic analysis obtained by using the finite element method is applied in order to determine the frequency variation diagrams of some nodes displacements, from some of the elements of the mechanism. Furthermore, the applied analysis seeks to identify the critical frequencies and the corresponding phase angles by investigating the displacements, the strains and the stresses of the mechanism elements, which correspond to critical frequencies and phase angles.

The paper presents a method for obtaining the power of thermal source, based on finite element approach, when the temperature distribution is known from an infrared image. The method is solving for the load vector, and extracts the power at element level from this vector.

In this paper the knee joint biomechanics during squat exercises is studied. Using an acquisition system based on electro-goniometers, measurements of flexion-extension knee angle during squat movement on a sample group of healthy subjects are performed. For each subject the curves of knee squat angle are normalized and the mean squat cycle of each subject and the final medium cycle are determined. The phase plane portraits are used to characterize the kinematics of the biomechanical system. Using ADAMS software, the forces components and the resultant connection force during squat cycle in the human knee joint are determined.

This study presents the authors research to develop a powered wheelchair for disabled people. The wheelchair is intended mainly for use in buildings area. The proposed solution for the wheelchair propulsion uses a chain transmission for each wheel and two motors. The benefits of the chain transmission, from ergonomic aspect is that they ensure the wheelchair folding for easy transportation with a vehicle and allows the motors placing in the front, thus providing better stability to access ramps and for climbs. From dynamic perspective, implementation of a chain transmission in the wheelchair propulsion, improves dynamic performances by multiplying the torque. Simulations performed in ADAMS reveal optimal performance of the wheelchair. Based on the proposed design of the wheelchair a prototype is manufactured and are presented experimental obtained results for motion analysis.

In this study, a drill dynamometer for measure dynamic forces and torques, using strain gauge transducers has been designed, manufactured and tested. The dynamometer is connected to a HMB data acquisition system. Drill forces signal are captured processed and transformed into numerical data with the help of hardware and software of the MGC. Plus acquisition system. The principle of the dynamometer measurement is based on strain gauge transducers which measures elastic deformations produced by the loads. The elastic element used in the construction consists in a spoked wheel which measures simultaneously the force and torque. The elastic deformations produced by the force and torque, bends the double embedded spokes. It is presented the dynamometer design and principle of measuring. In order to verify the elastic element deformations, it is performed a FEA analysis in ANSYS. The experimental model is calibrated and in the final stage is made experimental measurements of drill force and torque.

The paper explores one of the most useful and interesting facilities for a CAD system: the bilateral relation with a database. This connection allows the development of a new tire in data management, establishing a permanent relation between graphic information (handled by a CAD system), and non graphic information (handled by a database manager). The novelty of the paper consists in exposing the internal mechanisms of data management, which are the basis of handling foreign data in Mechanical Desktop environment. All the considerations are done for version 6 of Mechanical Desktop, in connection with the version 15 of ARX library.

The research of managerial behavior in Romanian organizations – COMOR - aims to identify the particular features of cultural indices’ manifestation form compared to those described in the specialized literature so to provide to those interested information useful to the practices of performing management in the context of economic globalization. The study includes about 300 business organizations from all counties and areas of activity and is based on the opinions expressed by a sample of approximately 6.000 respondents from all demographic, educational and organizational hierarchy layers. This material refers to the methodological benchmarks based on which the research is conducted.

We discussed how database fit within an information system in an organization and the different phases of the database design process. The database deign process include six phases, but the most important are conceptual design, logical design (data model mapping), and physical design.

Complexitatea procesului managerial, si mai ales amploarea si diversitatea implicatiilor acestuia asupra evolutiei individuale, de grup sau sociale ale oamenilor, constituie argumente hotarâtoare ce impun evaluarea muncii întregului personal din cadrul firmelor. Chiar daca managerii sunt cei care fac în general evaluarile, totusi se impune ca si activitatea manageriala sa fie ea însusi evaluata. Pentru a stabili daca activitatea managerului firmei este eficienta aceasta este supusa evaluarii. Stiinta si practica conducerii stiintifice reprezinta un vector de baza al cresterii economice. Eficienta activitatii managerilor se masoara prin rezultatele obtinute de catre acestia. Pentru un manager, eficienta înseamna ceea ce reuseste sa realizeze într-o anumita situatie pe care o stie a o exploata în mod corespunzator.