Adrian Ghionea

Assisted Research of the Neural Network

In the optimization of the trajectory or of the guidance of mobile robots one of the more important things is to assure one small difference between the output data of the system and the target. This paper show how on-line will be possible to establish one convergence way to the target without any influences of the input data or initial conditions of the weights or biases. The paper show the general components and the mathematical model of some more important neurons and one numerical simulation of the linear neural network. In the paper was used the least mean square (LMS) error algorithm for adjusting the weights and biases and incremental training by different training rate, finally to obtain one minimum error to the target.

Lathe Machining in the Era of Industry 4.0: Remanufactured Lathe with Integrated Measurement System for CNC Generation of the Rolling Surfaces for Railway Wheels

Many projects and researches in the field of remanufacturing of specialized lathes are presented in the specialized literature. In the process of design for remanufacturing, a great number of solutions contain different aspects and data important to consider. The paper presents important stages of theoretical and applied research regarding the modernization of a conventional lathe with two working units by adaptation of four driving chains for CNC advance/positioning movements and improvements of translation couplings, adaptation of CNC equipment for driving and measuring simultaneous both wheels mounted on axle. The reducing of geometrical errors of the running profile is very important in reshaping the worn wheelsets. The lathe remanufacturing process involves the restoration of functional requirements and measurement of the geometric precision. The CNC capabilities of the remanufactured lathe require a database of parametric representation of profiles and rolling surfaces using CAD techniques according to international standards.

Simulation of the Machining Process for a Spur Gear Pump Body - A Practical Study

The paper presents theoretical and applicative aspects concerning the construction, machining technology analysis of a spur gear pump body. For the machining process it is chosen a numerically controlled milling machine tool. The part analysed represents the main component of a hydraulic pump from the current production of a Romanian company. From a technical point of view, the part is highly complex due to the shape and dimensional precision, assembly and operation conditions of the pump as a whole. The authors propose some considerations related to optimization, choice of cutting tools, cutting depths, working mode parameters, reduction of the machining and auxiliary times, etc. The CAM simulation results provide many useful, tabular data that highlight the options to choose optimal machining variants.

Determination of the Milling Conditions of a Pump Casing Cover Using a Parametric Designed Fixture Device

This paper presents an applicative methodology of parametric computer aided design using the CATIA v5 software to model and assembly a modular fixture device. The device is then used in the orientation and clamping a part of type casing cover which has a face machined by milling. Having a constructive solution of the fixture device, the next step is to simulate a milling process through a FEM analysis to identify the working conditions: milling tool diameter, number of teeth, cutting forces, required power of the machine tool etc. Some parameters were chosen according to various tools manufacturers catalogues and the cutting force components were determined experimentally in laboratory conditions. The analysis results show that in the FEM simulated milling process, in all the fixture device parts, some tensions cause displacements that have an influence over the casing cover surface roughness.

Researches on Milling Machining of Planar Thin Wall Parts

In the paper are presented some experimental and by simulation results obtained in the machining by milling of plane surfaces of thin walls parts. Two case studies are considered: when the thin wall is vertical and then the thin wall is horizontal positioned. Some values of the cutting force components are established using a modern dynamometer and a data acquisition system. The elastic deformation values of the machined part are also determined by experimental tests and simulated in a FEM analysis. Depending on the data that geometrically define the part and the cutting tools, their materials and the cutting parameters, are set values of the cutting forces and powers. There are presented the results of values comparison obtained by measuring during the processes with those established by applying FEM. Both case studies results lead to some remarks and useful recommendations for determining the machining parameters and the needed conditions for the technological system in the processing of parts with thin walls and minimum deformations.

Diagnosis and Predictive Maintenance of Machinery and Equipment, by Measuring Vibration

The paper presents results of analysis of the dynamic behavior of rotating mechanisms and couplings of the main structure of a kinematic chain sharpening machine precision Cugir normal UAS 200. The ultimate goal is to establish diagnostic and maintenance program the car UAS 200. Diagnosis by measurement of vibration and noise, allow a company to monitor faults and machines and equipment, through a system of preventive maintenance, predictive. Diagnosis automatic machinery and equipment is made in order to ensure a higher reliability of these and how to obtain a more extended life cycle without the occurrence of defects. The application of preventive and predictive maintenance management supports enterprise, because it proves effective, the information you provide in making decisions.

Robotic Welding Cells Configuration

This paper deals with electric arc robotic welding, the main objective being the optimal structure configuration of the flexible Robotic Welding Cells (RWC). To this purpose, the authors propose a new algorithm for the configuration of the cell structure based on a set of optimization criteria. Thus, to determine the optimum RWC structure, the working cycle of the technological welding process and some process parameters influencing the welded ensemble are improved as well.

Establishing the State of Operation on Vibration Behavior of the Industrial Robot

Diagnosis measurement of vibration and noise, should allow monitoring of equipment defects, through a system of preventive maintenance, predictive. Automatic diagnosis of machinery and equipment was made in order to ensure a higher reliability of these and how to obtain a more extended life cycle without the occurrence of defects. Vibrations are always measured in analog format (time domain) and must be transformed into the frequency domain. Therefore Fast Fourier Transform (FFT) method is used to evaluate vibration Almega AX-V6 robot. The application of preventive and predictive maintenance management supports enterprise, because it proves effective, the information you provide in making decisions.

The Mathematical Model for the Generation of the Cylindrical Gear With Curved Cycloidal Teeth

The performed studies regarding the cylindrical gears with curved teeth or in V showed that a uniform distribution of the load on the flanks is hard to realise, generally being necessary later finishing processing or modifying the gear by camber or flanking, which suppose supplementary expenses. On the basis of these mentions and taking into account the advantages of curved bevel gear, the purpose of this paper is to present an original study regarding the mathematical model for generation of a curved cylindrical gear with high performances. The cycloidal gear was chosen after a technical and an economical study regarding on the possibility of practical implementation with the lowest production costs using a special device, adapted on a Phauter processing machine of cylindrical gear. This was the main reason for choosing a cycloidal profile from several types of curved teeth (cycloidal arc, circle arc, Archimede’s spiral, involute arc). So, the main aim of the paper is to determine the equations of the flanks of cylindrical wheel with curved teeth in oblong cycloidal arc, in order to establish if the technical generation is possible. The curved cylindrical teeth with cycloidal flanks is generated by rolling with straight mobile line and continuous division by using a milling cutter with 1, 2, 3, 6 groups of knifes equidistantly placed, fixed on an adaptable device on a Phauter processing machine. The two curves which define the flank are simultaneously generated by correlated motions, and the flanks of the wheel part result as a roll of successive positions of generating hook materialized by the cutting edge of the tool. The shape of the contact curve between the conjugated surfaces of generating element and the wheel part can be obtained if you are taking into account the kinematic condition. Using this condition you can determine the relationship between the kinematic, geometric and technological parameters. The line of the flanks is studied in the reference plane and in parallel planes with this, and the profile of the flanks is determined in perpendicular planes on the work piece axis. Based on the parametric equations it was made the simulation program in MATLAB that indicates that this gears can be obtained, and constitutes the first step in practical manufacturing of this kind of gears. By analyzing the obtained shape they result useful conclusions for the manufacturing of the involute-tooth gear with curved oblong cycloidal arc. On the other hand, using Solid Edge it was made the spatial modeling of the cylindrical gear with curved cycloidal teeth that allows next FEA studies regarding on the contact and bending stress.Copyright

Contributions to the Study of Generation of the Flanks of the Generating Hook of Cylindrical Curved Gear in Oblong Cycloidal Arc

The paper has proposed to determine the equation of flanks of generation hook with oblong cycloidal arc taking into account two types of cutting tool: a cutting tool that generates the hole of the tooth, respectively a cutting tool that generates the tooth. The curved cylindrical teeth with cycloidal flanks is generated by rolling with straight mobile line and continuous division by using a milling cutter with 1, 2, 3, 4 or 5 groups of knifes equidistantly placed, fixed on an adaptable device on a Phauter toothing machine. The two curves which defines the flank are simultaneously generated by correlated motions. In order to make the analytical study of motions and geometry of the flanks, several 3D coordinating systems were first defined, each of them being bounded by an element that participates in the generating process. There were established the equations of cutting edged of the tool in Ss system, the equations of the flanks of the generating hook are obtained by changing the reference system of edges of the tool from Ss to SCG . The line of the flanks is studied in the reference plane and in parallel plans with this, and. the profile of the flanks is determined in perpendicular plans on the workpiece axis. . It was made a calculation program in MATLAB, that allowed to obtain data, which were used to plot the line and the profile of the flanks of the generating hook. By analysing the obtained shape they result conclusions used for the manufacturing of the involute-tooth gear with curved oblong cycloidal arc.Copyright