Application of Automated Context-Based DSS for Determining CNC Machining Parameter

2012 ◽  
Vol 6 (6) ◽  
pp. 765-774
Author(s):  
Wikan Sakarinto ◽  
◽  
Setyawan Bekti Wibowo ◽  
Hiroshi Narazaki ◽  
Keiichi Shirase ◽  
...  

This paper describes the implementation of proposed KBS automatically aware of context or constraints in which the user has to deal with to come up with intelligent DSS. Context is a fundamental information resource that has to do closely with the use of knowledge. The proposedKBS is equipped with the Expert System (ES) providing Decision Support System (DSS), aimed for realizing effective utilization of captured CNC operator knowledge when they assess machining parameters within product data. The newest module in the proposed KBS is equipped with automated contextbased DSS constructed from incoming task restraints and other related machining aspects, such as machining parameter values, cutting tool, workpiece material, etc. In this work, the discussions are focussing on CNC milling operations. According to the implementation result, CNC operators have shown enhanced accuracy on defining machining parameter values with respect to specific constraints.

2017 ◽  
Vol 261 ◽  
pp. 448-455
Author(s):  
Agathoklis A. Krimpenis ◽  
John G. Tsakanikas

A systematic and detailed approach in design and manufacturing of blow molds for bottles made of PET and PP plastic material with CAD/CAM software tools is presented, as many production errors and product deficiencies stem from inaccurate and imprecise tooling. Apart from high mold accuracy, proper planning also includes the minimization of mold machining costs, which mainly derives from CNC machining time and cutting tool wear. Blow mold design and manufacturing revolves around two major axes: (a) mold material and (b) machining parameter values. The former is critical in terms of production rates and mold life-cycle and the latter has a great impact on mold manufacturing cost, as well as on quality of the produced plastic bottles. Proper choice of machining parameters has a significant impact on thermal conductivity, durability, hardness, stiffness and roughness of the mold. The proposed methodology was implemented on three different test cases (beverage plastic bottles molds) and it was concluded that even the same machining parameter values offer the same mold quality.


Author(s):  
I D Carpenter ◽  
P G Maropoulos

The selection of tools and cutting data is a central activity in process planning and is often liable to an element of subjectivity. It is further complicated by the wide range of choice presented by the various operation types and the huge portfolio of cutters and inserts available from many different tool manufacturers. This paper describes a procedure to select consistently and efficiently tools for rough and finish milling operations performed on a computer numerical controlled (CNC) machining centre. A wide range of milling operations is considered, including faces, square shoulders, slots, T-slots, pockets, holes and profiles. An initial set of feasible tools is generated that satisfy the constraints of the tool type, the operation geometry, the insert geometry and carbide grade, the workpiece material and the machine tool capacity. Each tool consists of a holder and one or more indexable carbide inserts. Aggressive cutting data are generated for each feasible tool using a rapid search procedure in the permissible depth/width/feed space for good chip control. The cutting data are further refined by a set of technological constraints, which include tool life, surface finish, machine power and available spindle speeds and feeds. The overall cutting data optimization criterion is selected by the user from minimum cost, maximum production rate or predefined tool life. A new optimization criterion, called ‘harshness’, allows the user to influence the chip thickness that is achieved for any given cutter. Any feasible tools that fail to satisfy all the constraints and optimization criteria are discarded.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
I G.N.K. Yudhyadi ◽  
Tri Rachmanto ◽  
Adnan Dedy Ramadan

Milling process is one of many machining processes for manufacturing component. The length of time in the process of milling machining is influenced by selection and design of machining parameters including cutting speed, feedrate and depth of cut. The purpose of this study to know the influence of cutting speed, feedrate and depth of cut as independent variables versus operation time at CNC milling process as dependent variables. Each independent variable consists of three level of factors; low, medium and high.Time machining process is measured from operation time simulation program, feed cut length and rapid traverse length. The results of statistically from software simulation MasterCam X Milling, then do comparison to CNC Milling machine.  The data from experiments was statistical analyzed by Anova and Regression methods by software minitab 16.Results show that the greater feedrate and depth of cut shorten the operation time of machinery, whereas cutting speed is not significant influence. Depth of cut has the most highly contribution with the value of 49.56%, followed by feedrate 43% and cutting speed 0.92%. Optimal time of machining process total is 71.92 minutes, with machining parameter on the condition cutting speed is 75360 mm/minutes, feedrate is 800 mm/minutes and depth of cut = 1 mm. Results of comparison time machining process in software Mastercam X milling with CNC Milling machine indicates there is difference not significant with the value of 0,35%.


2011 ◽  
Vol 5 (4) ◽  
pp. 575-586 ◽  
Author(s):  
Wikan Sakarinto ◽  
◽  
Hiroshi Narazaki ◽  
Keiichi Shirase ◽  

This study is aimed at filling the gap between CAM and CNC operations. The problem is important in practice but has been rarely addressed in the resarch community. In practice, the machining parameters designed by a CAM operator are not always applicable to the machining process by a CNC operator due to several reasons such as tool wear, in-availability, inefficiency, etc. This is mainly due to the discrepancy of knowledge between CAM and CNC operators. To deal with this situation, this study proposes a knowledgebased model for capturing the know-how of CNC operators in the assessment of the product data (CAM files) produced by CAM operators. The assessment determines whether the designed machining parameters are appropriate or not before proceeding further to the machining process. This assessment is the main process where the know-how of a CNC operator is actualized. Based on the data extracted from CAM files, this study discusses a method that captures the knowledge of CNC operators in the process of an assessment. In this work, the discussion is focused on common CNC milling operations.


2020 ◽  
Vol 4 (3) ◽  
pp. 66
Author(s):  
Yubin Lee ◽  
Alin Resiga ◽  
Sung Yi ◽  
Chien Wern

The purpose of machining operations is to make specific shapes or surface characteristics for a product. Conditions for machining operations were traditionally selected based on geometry and surface finish requirements. However, nowadays, many researchers are optimizing machining parameters since high-quality products can be produced using more expensive and advanced machines and tools. There are a few methods to optimize the machining process, such as minimizing unit production time or cost or maximizing profit. This research focused on maximizing the profit of computer numerical control (CNC) milling operations by optimizing machining parameters. Cutting speeds and feed are considered as the main process variables to maximize the profit of CNC milling operations as they have the greatest effect on machining operation. In this research, the Nelder–Mead simplex method was used to maximize the profit of CNC milling processes by optimizing machining parameters. The Nelder–Mead simplex method was used to calculate best, worst, and second-worst value based on an initial guess. The possible range of machining parameters was limited by several constraints. The Nelder–Mead simplex method yielded a profit of 3.45 ($/min) when applied to a commonly used case study model.


2020 ◽  
Vol 10 (3) ◽  
pp. 179-190
Author(s):  
Paulus Wisnu Anggoro ◽  
Abet Adhy Anthony ◽  
Mohammad Tauviqirrahman ◽  
Jamari ◽  
Athanasius Priharyoto Bayuseno ◽  
...  

In this study, ethylene-vinyl acetate (EVA) foam orthotic shoe insoles with different surface roughnesses (Ra) are investigated in terms of CNC milling strategy. Based on a hybrid Taguchi-response surface methodology (TM-RSM) approach, machining parameters, including tool path strategy, spindle speed, feed rate, and step over, as well as material hardness, are of particular interest. The main aim of this work is to develop mathematical models and determine the optimum machining parameters. Experiments are conducted on a CNC milling machine with a standard milling cutter and run under dry coolants. The optimal conditions are established based on TM and then used to determine the optimum values in the RSM modeling. The main finding of the present work is that there are significant improvements in the Ra, by up 0.24% and 4.13%, and machining time, by up 0.43% and 0.41%, obtained with TM-RSM in comparison to TM analysis.


2011 ◽  
Vol 5 (5) ◽  
pp. 655-662 ◽  
Author(s):  
Wikan Sakarinto ◽  
◽  
Hiroshi Narazaki ◽  
Keiichi Shirase

The main job of Computer Numerical Control (CNC) operators is to capture and use knowledge to assess product data. CNC operators assess Computer-Aided Manufacturing (CAM) files before proceeding to CNC machining processes. Decision Support Systems (DSS), for these operators, is provided by Expert Systems (ES) designed to manage and learn intelligently from previous data and information and produce recommended actions and decisions. The purpose of the DSS is (i) to assist inexperienced operators in assessment using stored know-how of experienced operators and to collect additional knowledge in interaction between the DSS and experienced operators during semiautomatic assessment, and (ii) to present collected knowledge to users based on contexts or constraints the user must deal with in product data assessment. After outlining the DSS, the discussion is about its usefulness in dealing information and knowledge discrepancies between CAM and CNC operators - an important problem in practice that has been rather neglected so far - focusing on CNC milling operations.


Author(s):  
Maxwell K. Micali ◽  
Hayley M. Cashdollar ◽  
Zachary T. Gima ◽  
Mitchell T. Westwood

While CNC programmers have powerful tools to develop optimized toolpaths and machining plans, these efforts can be wholly undermined by something as simple as human operator error during fixturing. This project addresses that potential operator error with a computer vision approach to provide coarse, closed-loop control between fixturing and machining processes. Prior to starting the machining cycle, a sensor suite detects the geometry that is currently fixtured using computer vision algorithms and compare this geometry to a CAD reference. If the detected and reference geometries are not similar, the machining cycle will not start, and an alarm will be raised. The outcome of this project is the proof of concept of a low-cost, machine/controller agnostic solution that is applied to CNC milling machines. The Workpiece Verification System (WVS) prototype implemented in this work cost a total of $100 to build, and all of the processing is performed on the self-contained platform. This solution has additional applications beyond milling that the authors are exploring.


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