Periodic cutting motions in a vibration-assisted, regenerative, nonlinear Orthogonal turning system

In order to optimize turning processes, cutting forces need to be accurately predicted. This in turn requires accurate extraction of the geometry of tool-workpiece engagements (TWE) at critical points during machining. TWE extraction is challenging because the in-process workpiece geometry is continually changing as each tool pass is executed. This paper describes research on a hybrid analytical, solid modeler, and feature-based methodology for extracting TWEs generated during general turning. Although a pure solid modeler-based solution can be applied, it will be shown that because of the ability to capture different cutting tool inserts with similar geometry and to model the process in 2D, an analytical solution can be used instead of the solid modeler in many instances. This solution identifies features in the removal volumes, where the engagement conditions are not changing or changing predictably. This leads to significant reductions in the number of Boolean operations that are executed during the extraction of TWEs and associated parameters required for modeling a turning process. TWE extraction is a critical component of a virtual turning system currently under development.

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A finite element analysis of orthogonal turning using different tool rake angle

2010 International Conference on Mechanic Automation and Control Engineering ◽

10.1109/mace.2010.5536095 ◽

2010 ◽

Author(s):

Li Zhou ◽

Shutao Huang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Rake Angle ◽

Element Analysis ◽

Orthogonal Turning

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Research on constantly tangential NC turning system for aspherical revolved curved surface

IEEE International Conference Mechatronics and Automation, 2005 ◽

10.1109/icma.2005.1626671 ◽

2006 ◽

Cited By ~ 1

Author(s):

Liu Hong ◽

Yao Jin ◽

Li Shangzheng ◽

Zhang Risheng

Keyword(s):

Curved Surface ◽

Turning System

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Cryogenic orthogonal turning of Ti-6Al-4V

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-020-06105-z ◽

2020 ◽

Vol 111 (1-2) ◽

pp. 359-369

Author(s):

Benedict Stampfer ◽

Philipp Golda ◽

Robert Schießl ◽

Ulrich Maas ◽

Volker Schulze

Keyword(s):

Process Variations ◽

Dry Cutting ◽

Cooling Fluid ◽

Workpiece Surface ◽

Supply Channel ◽

Orthogonal Turning ◽

Commercial Applications ◽

Machining Operations ◽

First Time ◽

Cryogenic Cutting

Abstract Cooling of machining operations by liquid nitrogen is a promising approach for reducing cutting temperatures, increasing tool life and improving the workpiece surface integrity. Unfortunately, the cooling fluid tends to evaporate within the supply channel. This induces process variations and hinders the use of nitrogen cooling in commercial applications. In this work, the coolant is applied via the tool’s rake face during orthogonal turning of Ti-6Al-4V. The effect of a nitrogen supply pressure adjustment and a subcooler usage—proposed here for the first time for machining—is analyzed in terms of process forces, tool temperatures and wear patterns, taken dry cutting as a reference. Thereby, reliable cooling strategies are identified for cryogenic cutting.

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A Method of Automatic Page Turning System for Various Types of Book Originals

Advances in Information Storage Systems ◽

10.1142/9789812815910_0015 ◽

1999 ◽

pp. 211-222

Author(s):

Kazunori Bannai

Keyword(s):

Turning System

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Determination of Inner and Outer Modulation Dynamics in Orthogonal Cutting

Journal of Engineering for Industry ◽

10.1115/1.3187129 ◽

1987 ◽

Vol 109 (4) ◽

pp. 275-280 ◽

Cited By ~ 5

Author(s):

T. Y. Ahn ◽

K. F. Eman ◽

S. M. Wu

Keyword(s):

Orthogonal Cutting ◽

Theoretical Background ◽

Cutting Process ◽

Experimental Realization ◽

Process Dynamics ◽

Orthogonal Turning ◽

Machine Tool Structure ◽

Dynamic Cutting Force ◽

Experimental Errors ◽

Modeling Strategy

Many efforts have been devoted in the past to the identification of the dynamic behavior of the cutting process. Nevertheless, there have been no consistent results due to the inherent complexity of the cutting process, and the methodological and experimental errors involved. Among the problems to be solved, the experimental realization of the double modulation is the most difficult one. Present approaches use elaborate instrumentation and assume the delayed inner modulation for the outer modulation. This assumption may not hold under all circumstances and it will be modified in this paper. The present method approaches the cutting process as a one-input one-output process consisting of the inner modulation and dynamic cutting force component. The application of bivariate time series models give the transfer function of the inner modulation dynamics. The outer modulation dynamics’ effect on the cutting process is subsequently determined from the disturbance noise dynamics. The theoretical background for the proposed approach along with a new modeling strategy has been introduced in detail. The experimental verification of the theoretical postulates and the identification of the cutting process dynamics were carried out using actual data collected from an orthogonal turning process of a tubular workpiece. External white noise excitation was used and the experimental setup was designed to minimize the errors caused by inertia and disturbances. Although the proposed method requires prior knowledge of the machine tool structure, it requires a comparatively simple experimental procedure and minimizes the possible errors associated with the signal processing task.

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Using a Vibration Absorber to Suppress Chatter Vibration in Turning Process With a Worn Tool

Volume 1: 22nd Biennial Conference on Mechanical Vibration and Noise, Parts A and B ◽

10.1115/detc2009-86100 ◽

2009 ◽

Cited By ~ 3

Author(s):

Hamed Moradi ◽

Firooz Bakhtiari-Nejad ◽

Mohammad R. Movahhedi

Keyword(s):

Transmission Lines ◽

Gas Turbines ◽

Block Diagram ◽

Vibration Absorber ◽

Vibration Absorbers ◽

Turning Process ◽

Electrical Transmission ◽

Chatter Suppression ◽

Orthogonal Turning ◽

Dynamic Vibration Absorbers

Dynamic vibration absorbers are used as semi-active controllers to reduce the undesirable vibrations in many applications such as electrical transmission lines, helicopters, gas turbines, engines, bridges and etc. One type of these absorbers is tunable vibration absorber (TVA). In this paper, regenerative chatter in an orthogonal turning process is suppressed using a (TVA). It is shown that TVA can modify the frequency response function of the cutting tool so as to improve cutting stability in turning process. In addition, tool wear is an important factor which works as a positive damping and helps the chatter suppression beside exertion of the TVA. Finally, using the SIMULINK Toolbox of MATLAB, the analog simulated block diagram of the problem is developed. The advantage of this simulation is that, one can analyze the effect of other types of excitations such as step, ramp, etc on the absorbed system.

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