Lyapunov Control Strategy for Thermoelectric Cooler Activating an Ice-Clamping System

2018 ◽  
Vol 10 (4) ◽  
Author(s):  
Alexandra Mironova ◽  
Paolo Mercorelli ◽  
Andreas Zedler
Keyword(s):  
Manufacturing Systems ◽  
Control Strategies ◽  
Industrial Applications ◽  
Machining Process ◽  
Free Form ◽  
Cooling Power ◽  
Machining Processes ◽  
Clamping System ◽  
Ice Strength ◽  
Free Form Surfaces

Deformation-free clamping plays an important role in manufacturing systems helping to ensure zero-defect production. The fixture of workpieces during machining processes poses challenges not only for microparts but also for thin-walled pieces or free-form surfaces in macromanufacturing. To address this challenge, a nontraditional adhesive technique, using frozen water to clamp, is introduced in this paper. By increasing the cooling power and thus reducing the temperature of the clamping plate, higher adhesive ice strength and, therefore, a safer clamping system during machining process, can be achieved. The objective of this investigation is to ensure a stable low temperature and to compensate for thermal disturbances. Thanks to their structural robustness, Lyapunov-based control strategies demonstrate an appropriate capability to achieve these results in real industrial applications. Model design of the clamping system as well as simulation and experimental results are shown and discussed.

Späne- und Stauberfassung bei der CFK-Zerspanung*/Extraction of chips and dust in machining operations of CFRP. Investigation on CFRP dry machining in industrial applications

2018 ◽  
Vol 108 (06) ◽  
pp. 473-478
Author(s):  
A. Gebhardt ◽  
M. Schneider
Keyword(s):  
Industrial Applications ◽  
Machining Process ◽  
Dry Machining ◽  
Machining Processes ◽  
Dry Cutting ◽  
Clamping System ◽  
Cutting Processes ◽  
Machining Operations

Bauteile aus CFK (kohlenstofffaserverstärkte Kunststoffe) werden meist spanend endbearbeitet. Diese Bearbeitung kann unter Überflutung durch KSS (Kühlschmierstoffe) oder trocken stattfinden. Die hier vorgestellte Studie zeigt für die Trockenzerspanung, wie die notwendige Erfassung von Stäuben und Spänen stattfindet, welche Technologien eingesetzt werden und wie eine Maschinen- und Bauteilreinigung aussieht.   A machining process is mostly used as a last step in the production of workpieces made of CFRP. In this machining process lubricants may be used or dry cutting processes are applicated. The here presented study shows for dry machining processes, which technologies are used for the dust and chip extraction. Furthermore, the techniques for the cleaning of the machine, the clamping system and workpiece are presented.

Multiresolution Representation of a Geometric Model for Free-Form Surfaces Turning Based on Mesh Simplification

2013 ◽  
Vol 823 ◽  
pp. 265-269
Author(s):  
Qing Zou ◽  
Jian Feng Lu ◽  
Yu Jiang Gao ◽  
Tao Wang ◽  
Jian Ning Yao ◽  
...  
Keyword(s):  
Tool Path ◽  
Control Method ◽  
Geometric Model ◽  
Mesh Simplification ◽  
Diamond Turning ◽  
Machining Process ◽  
Free Form ◽  
Multiresolution Representation ◽  
Resolution Model ◽  
Free Form Surfaces

In this paper, a new multi-resolution representation (MRR) of a series of intermediate shape models for FTS diamond turning based on mesh simplification is proposed. In this MRR, geometric relations between each resolution model can be controlled so as to avoid overcut and to level the cutting loads. The new control method for MRR is based on an improved Edge Collapse Algorithm with consideration of the curvature factor. In addition, the calculation method of machining allowance and tool path generation method are proposed to support the machining process. The effectiveness of the MRR has been verified through simulation.

Analysis of Non-Traditional Machining Processes Using Machine Learning

2021 ◽  
pp. 195-202
Author(s):  
Somnath Das
Keyword(s):  
Machine Learning ◽  
Manufacturing Systems ◽  
Complex Dynamics ◽  
Rapid Development ◽  
Machining Process ◽  
Machine Learning Techniques ◽  
Machining Processes ◽  
High Quality ◽  
New Developments ◽  
Learning Techniques

The nature of manufacturing systems faces increasingly complex dynamics to meet the demand for high quality products efficiently. One area, which experienced rapid development in terms not only of promising results but also of usability, is machine learning. New developments in certain domains such as mathematics, computer science, and the availability of easy-to-use tools, often freely available, offer great potential to transform the non-traditional machining domain and its understanding of the increase in manufacturing data. However, the field is very broad and even confusing, which presents a challenge and a barrier that hinders wide application. Here, this chapter helps to present an overview of the available machine learning techniques for improving the non-traditional machining process area. It provides a basis for the subsequent argument that the machine learning is a suitable tool for manufacturers to face these challenges head-on in non-traditional machining processes.

scholarly journals The Effect of the Feed Direction on the Micro- and Macro Accuracy of 3D Ball-end Milling of Chromium-Molybdenum Alloy Steel

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4038
Author(s):  
Balázs Mikó ◽  
Bálint Varga ◽  
Wojciech Zębala
Keyword(s):  
Surface Roughness ◽  
Metal Cutting ◽  
Tool Path ◽  
End Milling ◽  
Cutting Parameters ◽  
Machining Process ◽  
Free Form ◽  
Dimensional Error ◽  
Ball End Milling ◽  
Free Form Surfaces

The machining of free form surfaces is one of the most challenging problems in the field of metal cutting technology. The produced part and machining process should satisfy the working, accuracy, and financial requirements. The accuracy can describe dimensional, geometrical, and surface roughness parameters. In the current article, three of them are investigated in the case of the ball-end milling of a convex and concave cylindrical surface form 42CrMo4 steel alloy. The effect of the tool path direction is investigated and the other cutting parameters are constant. The surface roughness and the geometric error are measured by contact methods. Based on the results, the surface roughness, dimensional error, and the geometrical error mean different aspects of the accuracy, but they are not independent from each other. The investigated input parameters have a similar effect on them. The regression analyses result a very good liner regression for geometric errors and shows the importance of surface roughness.

scholarly journals 3D FE Modelling of Machining Forces during AISI 4140 Hard Turning

2020 ◽  
Vol 66 (7-8) ◽  
pp. 467-478 ◽  
Author(s):  
Anastasios Tzotzis ◽  
César García-Hernández ◽  
José-Luis Huertas-Talón ◽  
Panagiotis Kyratsis
Keyword(s):  
Hard Turning ◽  
Cutting Speed ◽  
Industrial Applications ◽  
Machining Process ◽  
Depth Of Cut ◽  
Machining Processes ◽  
Fe Modelling ◽  
Machining Force ◽  
Aisi 4140 ◽  
Force Components

Hard turning is one of the most used machining processes in industrial applications. This paper researches critical aspects that influence the machining process of AISI-4140 to develop a prediction model for the resultant machining force-induced during AISI-4140 hard turning, based on finite element (FE) modelling. A total of 27 turning simulation runs were carried out in order to investigate the relationship between three key parameters (cutting speed, feed rate, and depth of cut) and their effect on machining force components. The acquired numerical results were compared to experimental ones for verification purposes. Additionally, a mathematical model was established according to statistical methodologies such as the response surface methodology (RSM) and the analysis of variance (ANOVA). The plurality of the simulations yielded results in high conformity with the experimental values of the main machining force and its components. Specifically, the resultant cutting force agreement exceeded 90 % in many tests. Moreover, the verification of the adequacy of the statistical model led to an accuracy of 8.8 %.

Software Dedicated to Determining a Strategy of Coordinate Measurements

2019 ◽  
Vol 957 ◽  
pp. 179-186
Author(s):  
Marek Magdziak ◽  
Dominika Ziaja
Keyword(s):  
Free Form ◽  
Coordinate Measuring Machines ◽  
Machining Processes ◽  
Matlab Software ◽  
Measurement Strategy ◽  
Coordinate Measurements ◽  
Free Form Surfaces ◽  
Cam Software

The paper presents the developed software dedicated to determining a measurement strategy of contact coordinate measurements conducted by using coordinate measuring machines. The created software enables to calculate locations of the scanning lines along free-form surfaces of measured workpieces. The presented program was developed by using the MATLAB software. The created program was tested based on the selected examples of curvilinear surfaces. Measurement points were located in the parts of surfaces characterized by the biggest form deviations resulting from machining processes. The calculated deviations were the results of simulations performed by using selected CAM software. The presented software increases the efficiency of measurement processes.

Model Based Feedrate Scheduling for Free-Form Surface Machining

2010 ◽  
Vol 4 (3) ◽  
pp. 273-283 ◽  
Author(s):  
Yaman Boz ◽  
◽  
Onur Demir ◽  
Ismail Lazoglu
Keyword(s):  
Threshold Value ◽  
Free Form ◽  
Machining Processes ◽  
Surface Machining ◽  
Scheduling Strategy ◽  
Model Based ◽  
Feedrate Scheduling ◽  
Deflection Analysis ◽  
Free Form Surface ◽  
Free Form Surfaces

Free-form surfaces are commonly used in the automotive, aerospace, biomedical, home appliance, and die/mold industries. Minimizing cycle times is crucial for free-form surface machining in today’s competitive market. Although there have been remarkable enhancements in the CAD/CAM industry, these enhancements lack physical insight into machining processes. This article presents a model-based feedrate scheduling strategy for 3-axis machining of free-form surfaces. In feedrate scheduling strategy, cycle time is minimized by off-line control of cutting forces under a threshold value between specified feedrate values. Using tool deflection analysis, surface form error can also be predicted. The proposed approaches are tested under various machining conditions and the results are presented in the paper.

On the Classification of Fitting Problems for Single Patch Free-Form Surfaces in Reverse Engineering

2001 ◽  
Author(s):  
Mohammed M. Shalaby ◽  
Ashraf O. Nassef ◽  
Sayed M. Metwalli
Keyword(s):  
Reverse Engineering ◽  
Geometric Modeling ◽  
Linear Optimization ◽  
Optimization Methods ◽  
Industrial Applications ◽  
Spare Parts ◽  
Free Form ◽  
Modeling Techniques ◽  
Free Form Surfaces ◽  
Die And Mold

Abstract The design and manufacture of free-form surfaces increased in industrial applications, especially for the re-manufacture of spare parts, or in the die and mold industry. Reverse engineering has become the status quo technique in reproducing parts whose original designs are no longer existing or for parts, which assume slightly different shapes after manufacturing as in the case of die and mold industry. Laser scanners have been used extensively in sampling points from parts surfaces. The sampled points are then fitted with a free-form surface using one of the geometric modeling techniques such as Bezier or B-Spline surfaces. Since Non-Uniform Rational B-Splines (NURBS) is the most general form of geometric modeling techniques, this paper presents the possible formulations of the fitting problem optimization and presents some guidelines of the choice of the independent NURBS parameters, once the control points are evaluated using least squares fitting. The work shows that the use of NURBS weights can provide better improvements for the significant reduction of the fitting error, rather than the widely used knot values. In addition the work shows that parts with semi planar surfaces do not need further refinement using non-linear optimization methods.

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