An approach to the evaluation of multivariate data during ball end milling free-form surface fragments

Measurement ◽  
2016 ◽  
Vol 84 ◽  
pp. 7-20 ◽  
Author(s):  
Jozef Beňo ◽  
Ildikó Maňková ◽  
Peter Ižol ◽  
Marek Vrabel’
2000 ◽  
Vol 123 (3) ◽  
pp. 369-379 ◽  
Author(s):  
Rixin Zhu ◽  
Shiv G. Kapoor ◽  
Richard E. DeVor

A mechanistic modeling approach to predicting cutting forces is developed for multi-axis ball end milling of free-form surfaces. The workpiece surface is represented by discretized point vectors. The modeling approach employs the cutting edge profile in either analytical or measured form. The engaged cut geometry is determined by classification of the elemental cutting point positions with respect to the workpiece surface. The chip load model determines the undeformed chip thickness distribution along the cutting edges with consideration of various process faults. Given a 5-axis tool path in a cutter location file, shape driving profiles are generated and piecewise ruled surfaces are used to construct the tool swept envelope. The tool swept envelope is then used to update the workpiece surface geometry employing the Z-map method. A series of 3-axis and 5-axis surface machining tests on Ti6A14V were conducted to validate the model. The model shows good computational efficiency, and the force predictions are found in good agreement with the measured data.


Author(s):  
Zhiyang Yao

In fabricating free-form surfaces, ball end mills are mainly used to reach the final surface finish requirements. In the milling processes, cutter engagement value measures what portion of the cutter is involved in machining at a given instant of time. This paper presents geometric algorithms for estimating cutter engagement values for ball end milling processes of tessellated free-form surfaces. The cutter engagement value calculated here can be used later on in generating efficient cutter paths, as well as performing adaptive feed rate controls.


2010 ◽  
Vol 102-104 ◽  
pp. 544-549 ◽  
Author(s):  
Chun Jiang Zhou ◽  
Hong Chun Chen

The development of surface high-speed machining has put forward higher demands for uniform cutting load and smooth cutting tool path. Most current tool-path planning methods are based on constant scallop height, but they have the disadvantage of path point redundancy during the path discretization process. To overcome the problem, a tool path generation method of equal approximation error in each step for free-form surface is presented based on geodesic principle and curvature judgment. In this method, the NURBS curve is employed to realize smooth transition for adjacent two tool paths in high-speed machining. A certain angle of inclination of flat-end milling cutter during multi-axis machining improves the machining efficiency. Because of the advantage of this machining condition, the cutter location point generation algorithm during the machining condition is given by the method. The method is verified and simulated by C++. Experiment results proved that it can obtain uniform cutting load and continuous smooth cutting tool path during surface high-speed machining by the proposed method.


2021 ◽  
Vol 15 (3) ◽  
pp. 335-342
Author(s):  
Takamasa Yamamoto ◽  
Ryo Matsuda ◽  
Masatoshi Shindou ◽  
Toshiki Hirogaki ◽  
Eiichi Aoyama ◽  
...  

Monitoring technologies have attracted attention in the factory automation fields that rely on the Internet of Things (IoT). However, it is difficult to monitor the process information from a round machining tool during rotating operations. Therefore, we developed a novel tool holder equipped with a wireless communication function to monitor tool vibrations. In the present study, we attempt to measure the tool holder vibrations during ball nose end milling processes using the servo driving information for different machine tools. We demonstrate that, using the developed tool holder with a wireless system, it is feasible to improve the machined free form surface by considering the servo driving information.


2003 ◽  
Vol 125 (3) ◽  
pp. 397-404 ◽  
Author(s):  
Rixin Zhu ◽  
Richard E. DeVor ◽  
Shiv G. Kapoor

In this paper, a process model-based approach has been proposed for monitoring and fault diagnosis in the multi-axis ball end milling process. Besides its ability to deal with complex cutting geometry in free-form surface machining, the method has the capability of not only detecting the presence but also estimating the magnitudes of faults, which include flute chipping, breakage and spindle/cutter axes runout. A threshold-based fault detection method is developed based on the analysis of harmonic power distribution in the cutting force signal. A genetic algorithm approach is used to search and determine the fault pattern and magnitudes. The new approach is validated through both constant cross-section cut and free-form surface machining tests on 1018 steel.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4038
Author(s):  
Balázs Mikó ◽  
Bálint Varga ◽  
Wojciech Zębala

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.


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