0000000000060009
AUTHOR
Melania Tera
showing 18 related works from this author
Low-cost motion control solution for industrial manufacturing systems
2011
This paperwork deals with a low-cost actuation solution, based upon induction motors, which was seldom used in the motion control systems, especially for the machine tools feed drives. A simulation approach, based upon a mathematical model of the induction motor, for tuning the controllers of the systems is presented. Experimental researches developed upon a two axes motion control system, both axes being driven by alternating current asynchronous motors were also performed in order to test the proposed strategies. The asynchronous motors, used as actuation devices were equipped with incremental rotary encoders and controlled by vector frequency inverters and DSP motion control cards were u…
Comparison between Deep-Drawing and Incremental Forming Processes from an Environmental Point of View
2019
Deep-drawing is an industrial forming process which allows the user to process large batches of sheet metals parts. One of the major drawbacks of this process is the complexity and the high cost of dies. In comparison incremental forming is a flexible process, allowing the user to obtain sheet metal parts without the need of using a die. The present paper aims to present a comparative study of the two forming processes by presenting the main advantages and drawbacks of each one. The comparative study, aimed on the industrial implementation of the incremental forming process requires a comparison of the two processes regarding the environmental impact. Thus, the results of the study will jus…
Contributions Regarding Incremental Forming Process of Bimetallic Sheets
2014
Incremental forming is a process with a high degree of novelty, so this paper describes first of all a series of theoretical principles of the incremental forming process. A main objective of the paper was the usage, as blanks in incremental forming process of bimetallic sheets. So the experimental researches have targeted the realising of parts with different shapes made from such type of blank. In the experimental researches was chosen as technological equipment for incremental forming the numerical controlled milling centre. The paper also present the tools used in incremental forming in order to obtain a hemispherical parts.
Comparative Study by Numerical Analysis on the Formability of Deep-Drawn Tailor-Welded Blanks
2012
The realising of complex parts by welding together and then deep-drawing metal sheets made of different steel types or even different metal types can have many advantages, such as decreasing the part’s weight, reducing the manufacturing costs and an increased dimensional precision. In order to benefit from these results, a detailed knowledge of the metal sheets’ behaviour during deep-drawing is necessary. The current paper aims to compare, using numerical simulations based on the finite element method, the deep-drawing behaviour of parts made of steel sheets of different thicknesses welded together in three different manners and also of a part made of a monoblock blank.
Study upon the kinematic simulation of the incremental forming carried-on using a serial industrial robot
2021
Abstract Incremental forming with contact between tool-sheet metal workpiece in a single point is an unconventional process which allow the user to manufacture parts by combining the vertical movement of the tool along Z-axis and the horizontal movements of sheet metal workpiece, which are performed in XY plane. As technological equipment able to control coordinated movements on three axes, CNC machining centers and industrial serial robots with six degrees of freedom are the most suitable. The paper introduces a study regarding the use of robots as technological equipment for the process, by means of simulation. Supplementary degrees of freedom and singularities avoidance are also consider…
Computer assisted techniques for the incremental forming technology
2013
The Asymmetric single point incremental forming (ASPIF) is a manufacturing technology with a high degree of novelty. Even if there are a significant number of research results reported in the literature, the industry has not been very enthusiastic to adopt and implement it on large scale. One of the main reasons for that is the lack of specific computer aided techniques and tools, which could be used to design and optimize the ASPIF process. The paper presents some methods to overcome this drawback, either by using some general purpose computer assisted tools or by developing new simple, yet effective methods. The proposed methods can be used in the preparation stage of computer automated m…
Improving the Manufacturing Accuracy of the Profiling Machines
2010
Abstract This paper presents the results of theoretical and experimental researches carried out with regard to the optimization of the dynamic behavior of a CNC laser cutting machine, in terms of cutting precision, for the case of flat metallic parts whose contours comprise right angles and which a profiling machine has to process continuously, without stopping in the corner points. It is aimed especially at detailing the influence of the numerical control equipment's setup on the size of the contouring errors and on the smoothness of the movement, factors that have a direct influence on the accuracy and that have been less addressed until now. The theoretical researches indicate that it is…
Dynamic Analysis of a 7 DOF Robot Using Fuzzy Logic for Inverse Kinematics Problem
2019
Abstract In this paper, a dynamic analysis for a redundant, serial robot, with seven degrees of freedom is presented. The dynamic model of the robot is based on importing a tri-dimensional CAD model of the robot into MATLAB®, Simulink®-Simscape™-SimMechanics™. One can import complete CAD assemblies, including all masses, inertias, joints, constraints, and tri-dimensional geometries, into the model. The first step for executing a dynamic analysis is to resolve the Inverse Kinematics (IK) problem for the redundant robot. Because this type of robot has seven degrees of freedom the IK resolution implies an infinite number of solutions. So, to be able to resolve the IK for this kind of robot a F…
Theoretical and Experimental Researches Regarding Multilayer Materials Used for Incremental Forming
2014
Although this represents a relatively recent development in the industry, the composite multilayer sheets are currently encountered in almost all industrial domains, due to the density, mechanical strength and energy absorption properties that are higher than those of the blanks realised from a single material. These materials are useful especially in domains such a the automotive industry, where the vehicles must fulfil simultaneously conditions of increased passenger safety, increased comfort, increase of the loading capacity in conditions of a reduced energy consumption. First of all the paper shows the types of multilayer sheets and their areas and areas of use, then the paper analyzes …
Using an Adaptive Network-based Fuzzy Inference System to Estimate the Vertical Force in Single Point Incremental Forming
2019
Manufacturing processes are usually complex ones, involving a significant number of parameters. Unconventional manufacturing processes, such as incremental forming is even more complex, and the establishment of some analytical relationships between parameters is difficult, largely due to the nonlinearities in the process. To overcome this drawback, artificial intelligence techniques were used to build empirical models from experimental data sets acquired from the manufacturing processes. The approach proposed in this work used an adaptive network-based fuzzy inference system to extract the value of technological force on Z-axis, which appears during incremental forming, considering a set of…
Study on the application of CAM techniques on CNC lathes with Y axis and driven tools
2021
Abstract CNC lathes with Y axes and driven tools are machine-tools with complex kinematic. Using CAM techniques to program these machines is a cumbersome process and could easily lead to collisions. Collisions may occur not only between tools and workpiece but also between the mobile elements of the CNC lathe. While CAM software package can identify the first type of collisions, for the second type supplementary measures must be taken. This work presents the build of a kinematic model of such a CNC lathe and how can the CAM techniques be improved by using this model.
Considerations regarding the use of technological equipment for indexed and continuous multi-axes machining
2017
CNC machine-tools are becoming more and more complex, with regards of kinematic capabilities, driving systems, HMI interfaces and controllers. Consequently, the prices of these machines are also increasing, being directly linked with the machine characteristics. Multi-axes kinematic is nowadays seen as the possibility of controlling the motion of the machine elements not only on translational axes, but also on rotational ones. There are mainly two types of CNC milling machines with multi-axes kinematic: indexed 3+1 and/or 3+2 axes and continuous 4 and/or 5 axes machines. This work will present some aspects regarding indexed multi-axis and continuous multi-axes machining.
Developing a Knowledge Base about the Technological Forces within the Asymmetric Incremental Forming Process
2015
Asymmetric single point incremental forming (ASPIF) has been recognized as a solution with potential in manufacturing small batches or single sheet metal parts. The approach presented in this paper presents the development of a knowledge base regarding the values of the technological force within the ASPIF process and the influence of some technological parameters such as feed, speed of the punch, thickness of the part and step, upon them. The method is based on the use of the information provided by the CNC machine sensors. Relationships between the torques developed by the drive motors on each axes and the technological forces will be set in order to refine the raw information displayed o…
Aspects of Improving the Cost-Performance Ratio for the Manufacturing of Small-Size Cast Parts
2010
Abstract The paper analyses some of the commercially available solutions for casting small-size metallic parts and outlines possible solutions that would reduce the cost of such systems while maintaining a high performance level. high performance level. One typical application area for small-size parts is human prosthetics, so the commercial casting machines analysed here are used mainly in this application domain. The paper shows how high-cost systems added to the machines for providing protective atmospheres can be replaced by low-cost solutions with the same results in terms of part quality. Moreover, a solution is described that avoids the typical drawbacks of the currently used casting…
Modular fastening system and tool–holder working unit for incremental forming
2019
Incremental forming can be usually unfolded either on CNC milling machine–tools or serial industrial robots. The approach proposed in this paper tackles the problem of designing a modular fastening system, which can be adapted for both above mentioned technological equipment. The fastening system of the sheet–metal workpiece is composed of a fixing plate and a retaining plate. The fixing and retaining plates will be made up of different individual elements, which can be easily repositioned to obtain different sizes of the part. Moreover, the fastening system has to be able to be positioned either horizontally (to be fitted on CNC milling machines) or vertically (to be fitted on industrial r…
Dynamic analysis of a five degree of freedom robotic arm using MATLAB-Simulink Simscape
2021
In this paper, a dynamic analysis for a 5 degree of freedom (DOF) robotic arm with serial topology is presented. The dynamic model of the robot is based on importing a tri-dimensional CAD model of the robot into Simulink®-Simscape™-Multibody™. The dynamic model of the robot in Simscape is a necessary and important step in development of the mechanical structure of the robot. The correct choice of the electric motors is made according to the resistant joint torques determined by running the dynamic analysis. One can import complete CAD assemblies, including all masses, inertias, joints, constraints, and tri-dimensional geometries, into the model block. The first step for executing a dynamic …
Determination of Technological Forces in the Incremental Forming Process
2013
The paper presents a joint theoretical and experimental approach to determine the technological forces within the asymmetric single point incremental forming ASPIF process, based upon a theoretical model, image processing and data acquisition. The first step of this approach was to develop a theoretical model of the forces within the process, based upon the model of a mechanical feed drive of a CNC milling machine. By means of this model, relationships between the resistant torque at the motor spindle level and the technological force on the movement axis could be determined. Using an image processing method, which allowed the user to extract information within the machines operator panel a…
Model of a CNC Feed Drive for On-Site Tuning of the Controllers for Single Axis Motion
2016
The accuracy of CNC machine-tools is heavily influenced by the correct tuning of the feed drives controllers. While an initial tuning is performed by the machine-tool manufactures, in time the values have to be changed by the user in order to preserve positioning and contouring accuracy of the machine. This paper presents a model of a CNC feed drive, for a particular CNC machine-tool, but with a high degree of generality. The objective is to provide the user the necessary knowledge, together with a simple, yet accurate simulation tool, in order to assist him in the process of tuning the controllers.