Applied Mechanics and Materials Vol. 823

Abstract: The curve line translation motion can be generated in the particular form of the circular translation, through mono-mobile mechanisms with articulated links of simple parallelogram type (with a fixed side) or through transmission with toothed belt with a fixed wheel. Also, the circular translation can be generated through planar mechanisms with two cylindrical gears with a fixed central wheel. It is mentioned that the two cylindrical gearings of the Fergusson mechanisms are both exterior and interior.

Abstract: The current paper presents an experimental study of the movements of plants, as well as various conclusions of the research. The main idea is that the general movement of a plant under the action of the wind is a very complex one, and it can be studied within the research for creating mechanical systems based on the same principles.

Abstract: Using the MathCAD software, this publication aims to develop a novel model to interpret the analytical results for an elastic structure as a substitute to flexible coupling between two misaligned axes. This model is used for the analysis of the motion of two deformed components comprising of the cardan joint, as well as the coupling with elastic plates.

Abstract: The paper deals with constructive and functional elements of an adjustable coupling with friction disks and adjustable driving planar mechanisms. The paper shows few conceptual and functional principles, introduce a new function for couplings and a new class of centrifugal couplings. It also presents structural elements of an innovative constructive solution of a centrifugal clutch with friction disks and adjustable centrifugal driving.

Abstract: This study aims to validate the use of R744 for a resonant twin piston compressor for domestic applications. The vapor-compression refrigeration is the most commonly approached method for cooling household appliances such as refrigerators and air conditioning systems. The R134a refrigerant is one of the most suitable refrigerants from an energetic point of view. R744 (CO₂) compressors are less efficient, but the fact that the R134a raises serious environmental issues pushes commercial trend towards the usage of R744 [1]-[3]. Use of R744 in household appliances is currently an open topic and no company has switched yet to the environmental-friendly alternative. In this paper the fill efficiency will be simulated in order to validate if a conventional compressor such as the opposite twin piston compressor is capable of filling with refrigerant when operating at a 50Hz frequency. Such a validation can enable further investigations regarding the replacement of R134a with R744.

Abstract: The subjects of this paper are the existing bearing mountings of a testing rig for chain or belt drives. Friction in transmission without bearings is calculated by subtracting the bearing friction from the global friction. This is why it is of maximal importance in the correct evaluation of experimental measurements on the rig to have accurate data on the friction on bearings. After the period of running in, friction on the bearings is measured at certain intervals in time, but also depending on rotational speed, load and lubricating oil temperature.

Abstract: In this paper a pumping systems for deep extraction is simulated using SolidWorks and ADAMS. The elastic displacement of a point on the flexible moving cable is analyzed. The dynamics of the system is characterized with phase plane, Poincaré maps, and Lyapunov exponents. The Lyapunovexponents represent the dynamic stability of the system. The largest Lyapunov exponents for three different angular velocity show the chaotic motion of the system

Abstract: In this paper is presented a new mathematical model which is intended to simulate the hysteretic phenomenon of SERB-C Romanian friction device for damping and dissipation of earthquake energy used for buildings. These devices have unusual shape of force-displacement loop which can be simulated with our new model which represents a specific adaptation of the well known Bouc-Wen hysteretic model. The purpose of this analytical simulation is to determine a relation for the hysteretic loop which was obtained by experimental tests performed by the authors. The mathematical model presented in this paper can be used in computational simulation of a building protected with these types of devices, in order to determine the anti-seismic performances of a Romanian friction building protection system.

Abstract: This paper presents a simulation made with ANSYS program on the stress and strain state of the node region of a reinforced concrete building subjected to earthquakes and equipped with devices for seism energy dissipation. This simulation includes the forces developed by the damping devices which act on these important nodes regions. The main goal of this simulation is to determine if the presence of the damping device at the supra-structure of the building is increasing the stresses and strains in the concrete and reinforcement bars of the node during earthquakes. For this study were used damping devices with damping forces depending on displacements. The results are very useful in the process of designing the damping system for the superstructure of the building and in the process of designing the reinforcements of the building nodes regions.

Abstract: The paper presents the functional analysis of a parallel robotic system used for transperineal prostate biopsy. A simulation system to study the robot functional analysis was developed using the integrated MATLAB software. Given the fact that the robotic system is used in a medical environment, it has to meet certain safety requirements indicated by the medical doctors. In order to fulfill these needs an appeal to complex simulation software has to be made to help choosing the best kinematic solution for the robotic system. The designed simulation software offers a correlation between the structure of the robot and the surrounding medical environment, pointing out its workspace and possible configurations that might harm the human patient during the biopsy.