Models for Machining Accuracy in Multi-Tool Adjustment

2020 ◽  
Vol 17 (3) ◽  
pp. 8067-8085
Author(s):  
N.D. Yusubov ◽  
H.M. Abbasova
Keyword(s):  
Degrees Of Freedom ◽  
Cutting Conditions ◽  
Technological System ◽  
Machining Accuracy ◽  
Six Degrees Of Freedom ◽  
Cnc Lathe ◽  
Deformation Properties ◽  
Angular Displacements ◽  
Influence Degree ◽  
Full Factorial

The article discusses the technology capabilities of multi-purpose CNC machines, and possible options for implementing parallel multi-tool processing. It was revealed that the technological capabilities of these machines are used at best by 50% in factories. This is due to the lack of recommendations for the design and use of such adjustments for these machines. To this end, generalised lattice matrix models of the accuracy of multi-tool machining have been developed in order to fulfill the requirements of algorithmic uniformity models and their structural transparency. The use of lattice matrices greatly simplifies the error in model of multi-tool machining and makes it extremely visual. Also, full-factorial distortion models and scattering fields of the dimensions of multi-tool machining performed on modern multi-purpose CNC lathe machines have been developed to take into account the angular displacements of the workpiece when machining parts with prevailing overall dimensions. They take into account the flexibility of the technological system for all six degrees of freedom to identify the influence degree of complex of technological factors on the machining accuracy (structure of multi-tool adjustment, deformation properties of subsystems of a technological system, cutting conditions). A methodology has been developed for determining the complex characteristics of compliance of a technological system. On the basis of the developed accuracy models in spatial adjustments, it is possible to develop recommendations for the design of adjustments for modern multi-purpose machines in CNC turning group (creation of CAD of multi-tool machining). Thus, it is possible to achieve a number of ways to control multi-tool machining, including improving the structure of multi-tool adjustment, calculating the limiting cutting conditions.

Control of processing at multi-tool two-support setup

2020 ◽  
pp. 67-73
Author(s):  
N.D. YUsubov ◽  
G.M. Abbasova
Keyword(s):  
Degrees Of Freedom ◽  
Factor Model ◽  
Angular Displacement ◽  
Factor Models ◽  
Technological System ◽  
Displacement Control ◽  
Model Accuracy ◽  
Six Degrees Of Freedom ◽  
Angular Displacements ◽  
And Control

The accuracy of two-tool machining on automatic lathes is analyzed. Full-factor models of distortions and scattering fields of the performed dimensions, taking into account the flexibility of the technological system on six degrees of freedom, i. e. angular displacements in the technological system, were used in the research. Possibilities of design and control of two-tool adjustment are considered. Keywords turning processing, cutting mode, two-tool setup, full-factor model, accuracy, angular displacement, control, calculation [email protected]

Full-factor matrix model of accuracy of dimensions performed on multi-purpose CNC machines

2021 ◽  
Vol 23 (4) ◽  
pp. 6-20
Author(s):  
Nizami Yusubov ◽  
◽  
Heyran Abbasova ◽  
Keyword(s):  
Matrix Models ◽  
Cutting Conditions ◽  
Machining Process ◽  
Technological System ◽  
Design System ◽  
Machining Accuracy ◽  
Factor Matrix ◽  
Cnc Machines ◽  
Plane Parallel ◽  
Base Points

Introduction. One of the main reasons that modern multi-purpose CNC machines do not use the capabilities of multi-tool processing is the lack of recommendations for design in this direction and, accordingly, for adjustment schemes. The study of the possibilities of multi-tool processing on multi-purpose machines is the subject of the work. The purpose of research: The problem of developing full-factor matrix models of dimensional accuracy and its sensitivity to the machining process is considered to increase the machining efficiency while ensuring machining accuracy using the technological capabilities of multi-tool machining on modern multi-purpose CNC machines. For this purpose, full-factor matrix models of the size scattering fields performed on multi-tool double-carriage adjustments have been developed, taking into account the cases of processing parts with dimensions that differ sharply in different directions, which are often encountered in practice, and in this case, the significant influence of the turns of the workpiece on the processing error, especially in directions with sharply different overall dimensions. Results of research: The developed accuracy models make it possible to calculate not only plane-parallel displacements of the technological system for double-carriage adjustments, but also angular displacements around base points, take into account the combined effect of many factors – a complex characteristic of the subsystems of the technological system (plane-parallel matrix of compliance and angular matrix of compliance), the geometry of the cutting tool , the amount of bluntness of the tool, cutting conditions, etc. As a result, based on the developed accuracy models, it is possible to obtain several ways to control multi-tool machining, including improving the structure of multi-tool adjustments, calculating the limiting values of cutting conditions. Based on the developed full-factor matrix models, it became possible to develop recommendations for the design of adjustments and the creation of an automated design system for multi-tool machining for a group of modern multi-purpose CNC lathes. Scope of the results: The results obtained can be used to create mathematical support for the design of operations in CAD-systems provided for multi-tool multi-carriage machining performed on multi-purpose machines. Conclusions: The developed models and methodology for simulating the machining accuracy make it possible to increase the accuracy and efficiency of simultaneous machining, to predict the machining accuracy within the specified conditions.

Dynamics Analysis of 6-DOF Platform under the Condition of Unbalanced Force

2013 ◽  
Vol 274 ◽  
pp. 658-662
Author(s):  
Liu Jie ◽  
Tang Yi ◽  
Li Hua Li ◽  
Xian Fei Li ◽  
Xiao Dong Liang
Keyword(s):  
Simulation Model ◽  
Mechanical System ◽  
Degrees Of Freedom ◽  
Dynamics Analysis ◽  
System Software ◽  
Gravity Center ◽  
Rational Use ◽  
Six Degrees Of Freedom ◽  
Unbalanced Force ◽  
Influence Degree

During the use of 6－DOF(six degrees of freedom) platform the gravity center of force tends to deviate from the center of the upper platform, resulting in six rods are forced unbalanced. This paper firstly introduces the characteristics of the 6－DOF platform, then establishes simulation model of platform through the PRO/E software, and analyses the kinematics of platform by use of the ADAMS (Automatic Dynamics Analysis of Mechanical System) software, finally proceeds with dynamics analysis of six rods in unbalanced condition.Those will get the influence degree of rods under the unbalanced force,and provide some proposal for the rational use of the platform.

"The Seven Claps" of Quan-Zhou Chest-Clapping with Motion Capture

2013 ◽  
Vol 311 ◽  
pp. 202-207 ◽  
Author(s):  
Si Xi Chen ◽  
Shu Chen ◽  
Jian De Lin ◽  
Jian Wei Li ◽  
Xin Chen
Keyword(s):  
Motion Capture ◽  
Degrees Of Freedom ◽  
Folk Dance ◽  
Motion Capture System ◽  
Basic Form ◽  
Six Degrees Of Freedom ◽  
Motion Data ◽  
Capture Method ◽  
Angular Displacements ◽  
Motion Capturing

This paper focuses on the motion capture method of the certain variety of South China traditional folk dance, Quan-zhou Chest-clapping. The authors used Vicon Motion Capture system to capture the motion of “the seven claps”, the basic form of Quan-zhou Chest-clapping Dance, and optimized the capture procedures and acting standards for the clapping and certain motions’ capture. To process the motion data , the authors used the Motionanalysis system to obtain the six degrees of freedom of certain basic dance motions, by measuring the motions’ maximum and minimum values of linear displacements and angular displacements on axis X ,Y and Z. Based on the measuring results of the motions’ degrees of freedom, the authors further discussed the quantification of motion course and developed the integrate exclusive motion capturing assessment criteria.

Accuracy Analysis of Machining Trajectory Contemplating Workpiece Dislocation on a Six Degree of Freedom Machining Bed

2020 ◽  
pp. 095440622097404
Author(s):  
Muhammad Faizan Shah ◽  
Zareena Kausar ◽  
Muhammad Umer Farooq ◽  
Liaquat Ali Khan ◽  
Syed Saad Farooq
Keyword(s):  
Material Removal ◽  
Degrees Of Freedom ◽  
Inverse Kinematic ◽  
Degree Of Freedom ◽  
Machining Accuracy ◽  
Leg Length ◽  
Computation Model ◽  
Six Degrees Of Freedom ◽  
Six Degree Of Freedom

Machining is material removal from a workpiece. Current spindle technologies allow the material to be removed very quickly but unfortunately this compromises the accuracy of the desired machined trajectory on the workpiece. Proposed solution to the problem is restricting motion of the tool and giving rotation to the workpiece. This paper presents analysis of the accuracy of trajectory of material removal from a workpiece, such that the workpiece rotates with six degrees of freedom, in the presence of error generated due to an offset of the workpiece from centre of the moving platform of the machining bed. The kinematics of the machining bed is, therefore, modeled using as inverse kinematic formulation applying geometric and vector addition method. The mechanism outputs three rotational and three translational motions. The leg length for each of six legs of the bed is computed individually. Moreover, workpiece position offset error is modelled to find actual leg lengths of the bed. Finally accuracy computation model is proposed to analyse the accuracy of the final trajectory of the motion of the workpiece. The models are verified in simulation for a trajectory and validated experimentally on a six degree of freedom (6DOF) machining bed. The results reveal maximum inaccuracy in machining trajectory to be 1% in experiments while less than 1% in simulation. This verifies quality of the mechanism and efficacy of the proposed 6DOF machining bed in machining accuracy.

scholarly journals Design and Calibration of a Hall Effect System for Measurement of Six-Degree-of-Freedom Motion within a Stacked Column

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3740
Author(s):  
Olafur Oddbjornsson ◽  
Panos Kloukinas ◽  
Tansu Gokce ◽  
Kate Bourne ◽  
Tony Horseman ◽  
...  
Keyword(s):  
Hall Effect ◽  
Degrees Of Freedom ◽  
Reactor Core ◽  
Degree Of Freedom ◽  
Life Extension ◽  
Scale Model ◽  
Design Development ◽  
Seismic Safety ◽  
Six Degrees Of Freedom ◽  
Six Degree Of Freedom

This paper presents the design, development and evaluation of a unique non-contact instrumentation system that can accurately measure the interface displacement between two rigid components in six degrees of freedom. The system was developed to allow measurement of the relative displacements between interfaces within a stacked column of brick-like components, with an accuracy of 0.05 mm and 0.1 degrees. The columns comprised up to 14 components, with each component being a scale model of a graphite brick within an Advanced Gas-cooled Reactor core. A set of 585 of these columns makes up the Multi Layer Array, which was designed to investigate the response of the reactor core to seismic inputs, with excitation levels up to 1 g from 0 to 100 Hz. The nature of the application required a compact and robust design capable of accurately recording fully coupled motion in all six degrees of freedom during dynamic testing. The novel design implemented 12 Hall effect sensors with a calibration procedure based on system identification techniques. The measurement uncertainty was ±0.050 mm for displacement and ±0.052 degrees for rotation, and the system can tolerate loss of data from two sensors with the uncertainly increasing to only 0.061 mm in translation and 0.088 degrees in rotation. The system has been deployed in a research programme that has enabled EDF to present seismic safety cases to the Office for Nuclear Regulation, resulting in life extension approvals for several reactors. The measurement system developed could be readily applied to other situations where the imposed level of stress at the interface causes negligible material strain, and accurate non-contact six-degree-of-freedom interface measurement is required.

Sign in / Sign up

Export Citation Format

Share Document