CNC Code Research Articles

Application of artificial neural network in predicting the performance of SPIF for aerospace grade AA7075-T6

Single Point Incremental Forming (SPIF) is recently been used to prepare customized parts with complex geometries. The vertical CNC-milling machine and CNC code are generally used to carry out the forming operation. The material used in the present study is aerospace grade AA7075-T6 due to its inherent properties of high strength-to-weight ratio. The input parameters such as annealing temperature, step depth, tool shape, and the number of cut-out blanks were taken into consideration. The Output parameters like surface roughness and formability were recorded and evaluated by developing an Artificial Neural Network (ANN) based prediction model. Both single-output and double-output neural networks were established for this purpose. In case of one-output structure, the training function of trainlm, transfer function of logsig and 8 no. of neurons whereas, the training function of trainlm, transfer function of tansig and 6 no. of neurons are found to be suitable combination for surface roughness and formability respectively. On the other hand, in case of two-output structure, the training function of trainlm, transfer function of tansig and 10 no. of neurons are found to be suitable. The MAPE and R-values of the developed ANN model denote good agreement with the experimental results. The developed model will reduce the cost, effort, and time of young engineers and practitioners to select accurate parameters without performing expensive experimental runs.

Enhancing engineering education through mini project-based learning in computer integrated manufacturing laboratory: A student-centric approach

ABSTRACT In response to evolving engineering education, there is a growing focus on fostering students’ practical skills. This study implemented a Mini Project Based Learning (MPBL) approach within the Computer Integrated Manufacturing (CIM) course. The tasks involved SOLIDWORKS modelling, writing CNC code using CADEM seeNC Turn software, and hands-on CNC machining by students. Quantifiable outcomes demonstrated the development of students’ CNC expertise. Numerical evidence showcased a significant increase in academic performance, with the percentage of students scoring over 80 marks rising from 33.33% in the previous academic year (CAY-M1) to an impressive 45.83% in the current academic year (CAY), highlighting the positive impact of MPBL. MPBL improved comprehension and enhanced critical thinking, collaboration, creativity, and communication skills. Its integration in CIM sparked creative enthusiasm among students and educators. Effective evaluation tools played a pivotal role in elevating project results, ensuring a holistic learning experience that integrated theory and engineering design.

A continuous oscillating milling strategy based on uniform wear theory for improving the service life of the ball-end cutter

The rapid deterioration of ball-end cutters leads to a shortened lifespan when milling difficult-to-cut materials. This research introduced a continuous oscillating milling approach aimed at enhancing the consistency of cutting-edge wear by dynamically adjusting the tool axis oscillation angle, thus prolonging the tool life. Initially, key processing parameters were determined according to the actual processing conditions. Subsequently, a tool wear model, rooted in continuous oscillating milling, was developed. Using it, an optimization framework for the tool oscillating angle, based on uniform wear theory, was established. Then, the CNC code was compiled according to optimization results. Finally, the proposed milling strategy was demonstrated by cutting tests on Ni-based superalloy GH4169. The results demonstrated that this approach notably extended the tool life.

Shaping of the Fresnel lens array on roller molds by 6-axis diamond machining

The Fresnel lens arrays are rapidly developing with the increasing demand for better optical performances and capabilities. For the roll-to-roll embossing of optical films, direct diamond machining of the Fresnel lenses on roller molds has been realized by installing an additional goniometer on the 5-axis ultra-precision machine tool in the previous study. However, this method owns two shortcomings, i.e., the communication delay between the machine tool and the goniometer and the poor positioning accuracy of the goniometer. In this paper, a 6-axis diamond shaping method is proposed to fabricate the Fresnel lens array on the roller periphery by utilizing a commercial 6-axis ultra-precision machine tool. It is ensured that the side cutting edge of the diamond tool matches the Fresnel lenses profiles during shaping. Also, the tool rake face is always perpendicular to both the roller tangent plane at the cutter location point and the cutting velocity relative to the roller via the synchronized rotations of the A-, B- and C-axes to avoid the tool–workpiece interference. The process to calibrate installation errors is introduced and utilized. The tool path is generated according to the cutting tool geometry, the lens parameters and the machine tool configuration. Experiments are carried out by machining the designed Fresnel lens array on a roller mold, which consists of lenses with different feature heights. The surface qualities of the lens arrays are evaluated and the influence of the block time to run the CNC code are also analyzed. The experimental results verify that the proposed method is effective and flexible for machining of the Fresnel lens array on roller molds.

Investigation of ultrasonic-assisted CNC cutting of honeycomb cores

As compared to traditional milling, ultrasonic-assisted cutting of honeycomb core materials has the advantages of small cutting force and superior surface quality. Currently, ultrasonic straight blade V-shaped machining is one of the most efficient roughing processes. The requirement of a processing path to be post-processed based on the processing characteristics of the straight blade cutter is one of the key issues faced while meeting the technological requirements of CNC machine tools for V-shaped machining. A post-processing method of NC code for V-shaped machining of straight blade cutter is proposed in this article. Initially, the V-shaped rough machining process planning is done, followed by the usage of Unigraphics (UG) to output the initial CNC code. Next, the CNC code is executed through the three key technologies of the second arrangement of cutter locations. Later, research is done on information planning of lifting and lowering cutter, along with research on planning of chip breaking toolpath. Eventually, the simulation cutting experiment is carried out through VERICUT. The results demonstrate that the post-processing method can meet the processing requirements.

CAD/CAM interfaced algorithm reduces cutting force, roughness, and machining time in free-form milling

A ball-end cutting tool is usually chosen to mill free-form surfaces in finishing operations. The cutting speed, which is calculated considering the nominal tool diameter, reduces along the tool path, according to tool-surface contact and the effective tool diameter. This brings several drawbacks to the manufacturing process. The current work presents a new algorithm to optimize CNC codes for milling free-form surfaces by parametrizing and adjusting the spindle frequency and the feed rate, considering the tool-surface contact. The proposed algorithm introduces new values for spindle frequency (S) and for feed rate (F) at each line of the CNC code, according to the surface topography. Machining experiments show that the proposed algorithm can reduce the milling time up to 40%, as well as reduce the machining force up to 21%, compared to the ordinary CNC codes. By keeping the cutting speed and feed rate constant, the surface roughness was improved—confirmed by ANOVA analysis—due to the increased shear mechanism rather than ploughing, especially in areas where the effective tool diameter is smaller.

Concept development for fabricating threaded micro-pin using wire-EDM

Nowadays miniaturization with precision is an important requirement in the field of medical devices and high-end applications. This work introduces the concept of 3D complex geometry fabrication in microscale using typical 2-Axis wire-cut electric discharge machine (WEDM). In this regard, the threaded profile micro-pin has been chosen in the present study. Synchronizing the workpiece rotating speed with feed rate along with a suitable depth of cut is the required condition for fabricating a screw. A separate attachment has been developed and used to rotate the workpiece at different speeds. Further, a CNC code has been generated to design the tool path with the required tool feed and depth of cut. Initially, turning operation has been performed which results in reduction in the tool diameter into the desired dimension along with the elimination of the eccentricity of the rotating rod. Consequently, the thread cutting operation has been accomplished with the adjusted set of parameters. Besides, the surface topography and material characteristics of the fabricated screw fin have also been observed based on scanning electron microscopic images and energy-dispersive X-ray analysis. Finally, the established process has been escalated further to fabricate screws of minimum possible dimension using the WEDM.

Construction Design and Manufacturing of a Cylinder Liner of a Motorcycle

This work deals with the construction design and manufacturing of a cylinder liner which is used in a Jawa 50 motorcycle in order to increase the performance characteristics. The liner is pressed in the aluminium cylinder case with ribs so together it makes a two-stroke motorcycle cylinder. The first step was to build an analysis of the technical design of the original motorcycle cylinder to detect any restrictive parameters for the modifications, especially of the cylinder liner, so the motorcycle can be used for racing. As well as the construction design of the liner, the work deals with the clamping and manufacturing of this part too. The CNC code was written using SolidCAM software. Then the liner was manufactured in a turning-milling centre. The purpose of this work is to produce a liner so that it forms a racing motorcycle cylinder together with the aluminium case with the ribs. The basis of this project is the correctness of the construction design and the accuracy in manufacturing so that the engine can achieve the demanded parameters with respect to usability, engine cooling, gear setup, engine life and the other restrictive parameters.

Development of web-based knowledge-based system for CAD modeling and manufacturing

With the aim of sustain in the present volatile market, the companies are looking for the alternate methods for designing and manufacturing. Web-based technologies have the potential to blend into the context of engineering design and manufacturing. This paper presents a preliminary approach for developing the web-based Knowledge-Based System for CAD modeling and 9manufacturing. The advanced CAD modeling techniques such as parametric modeling technique have been incorporated in the proposed system along with the macro codes for generation of the CAD model. The generated CAD model is the intermediate output of the proposed system and is the input to the CNC code generator to carry out the manufacturing processes. An inference engine and relevant web-UI are developed for assisting the design engineers. The intension behind the development of the system is to reduce the CAD modeling and manufacturing time and thereby reducing the production cost.

Automation of tool path generation in multi-process micromachine tool for micromachining of prismatic and rotational parts

ABSTRACTComputer numerical control (CNC) code generation is an inimitable activity of a Computer-aided manufacturing (CAM) system. Tool path formulation is considered as a machine-dependent activity, and expertise is essential to make attuned for a specific micromachine tool. This paper describes research for retrofitting of a multi-process micromachine tool for automatic CNC code generation for 2.5D micromachining. Micro turning, micro drilling and micro end milling processes are all considered. The proposed system comprises of three main elements: (i) part feature extraction through an extensible mark-up language (XML) schema, (ii) manufacturing logic formulation and CNC code generation by means of mathematical logic and (iii) online integration. XML-based feature extraction ensures trouble-free integration with the decision-making system. Automation of CNC code generation eliminates the need of human expertise, avoids compatibility issues and minimises program creation time. The developed system integrated with the micromachine tool through communication interface for real-time micromachining. The proposed system is intended for 2.5D machining of miniature and micro parts with external step, hole and slot features. The developed system performance has been validated through case study implementations.

Automatic extraction of vertices coordinates for CNC code generation for dental wire bending

This paper reports a new methodology for an automatic extraction of vertices coordinates from a dental wire CAD model in an initial graphics exchange specification (IGES) file format for CNC bending code generation. It has two main components, the first one deals with IGES feature extraction and the second one deals with autonomous CNC code generation based on the Cartesian coordinates using various mathematical formulae. The procedure is carried out in MATLAB environment through some developed functions to support wire design technique in CAD by means of 3D line segmentation. In this approach, the digital design of the wire is constructed from multiple 3D line segments in reference to the 3D teeth scan image (STL file). The developed methodology has three steps consisting of an IGES model pre-processing, automated coordinate extraction and CNC bending code generation. The developed methodology is limited to the CAD design through multiple line segments and has been verified with a case study.

Automatic extraction of vertices coordinates for CNC code generation for dental wire bending

This paper reports a new methodology for an automatic extraction of vertices coordinates from a dental wire CAD model in an initial graphics exchange specification (IGES) file format for CNC bending code generation. It has two main components, the first one deals with IGES feature extraction and the second one deals with autonomous CNC code generation based on the Cartesian coordinates using various mathematical formulae. The procedure is carried out in MATLAB environment through some developed functions to support wire design technique in CAD by means of 3D line segmentation. In this approach, the digital design of the wire is constructed from multiple 3D line segments in reference to the 3D teeth scan image (STL file). The developed methodology has three steps consisting of an IGES model pre-processing, automated coordinate extraction and CNC bending code generation. The developed methodology is limited to the CAD design through multiple line segments and has been verified with a case study.

A New Method of Diminishing Errors of Form Generated by the Imprecision of CNC Machines

Abstract During the processing of the helical surfaces on CNC machines, independent of the number of axes of the machine, there will certainly appear geometric deviations from the theoretical profile. Errors of form, which appear in this situation, can be detected through successive measurements. In order to diminish them, it is possible to use a method of compensation the deviations previously measured, which consists in adapting the CNC code used to obtain the helical profiles to the conditions required by the imprecision generated by the geometry of the machine.

Automatic Generate CNC Code for Symmetrical Object

This project “AUTOMATIC GENERATE CNC CODE FOR SYMMETRICAL OBJECT” mainly focuses in cloning any symmetrical object from any remote area. First, software is created which is meant to generate CNC codes for lathe automatically and it sends the generated codes to any part of the world with the help of internet in a fraction of second, this also can be said as live object transfer. The software has a scanning window which is used to scan the object and to find the dimensions of the object. The object is captured using a video camera and stored as an image. This image is then scanned for its dimensions using image processing technique with the help of scanning software. These dimensions are used to write the special standardised codes meant for the CNC Lathe, the G & M codes. Hence the codes to make the object are generated. The generated codes are transferred through internet to any part of the world in a fraction of seconds. The specialty of this project is, the scanning, the automatic generation of CNC codes, sending the generated codes to any remote area all these things happens in a fraction of seconds.

A New Optimization CAD/CAM/CAE Technique for the Processing of the Complex 3D Surfaces on 5 Axes CNC Machines

Abstract In the case of complex surfaces, the processing on 5 axes CNC machines may be approached by taking into consideration the fact that the axis of the cutting tool must stand in a normal direction towards the plan of the surface that needs processing. In this case, a data file will be used, which will be transferred to an application which is capable of generating the CNC code that can be recognized by the programming language of the machine. At the same time, in order to optimize this procedure, the processing of the 3D solid surfaces may be approached. In this case, the piece which is considered a solid, may be decomposed into successive sections that will optimally be processed on the 5 axes CNC machine using the facilities of the 5 axes CNC machine. One viable solution that can be applied in the case of the processing of the 3D surfaces is the decomposition of a solid into successive sections, according to the processing plan. If we use the procedure above described for the processing of the 3D complex surfaces, essential benefits will occur, related to the conditions of the processing, using a cutting tool on a 5 axes CNC machine, especially as compared to the 3 axes CNC machine. In the case of the processing procedure of a 3D complex surface held on a 3 axes CNC machine, risks may appear, such as obtaining a surface with form errors caused by inappropriate position of the cutting tool towards the generated outline. This inconvenient may be eliminated when using a 5 axes CNC machine. This procedure is the subject of the study presented in this article.

Research on CNC Machining System of Directly Driven by Image Based on PMAC

This paper establishes a system that can automatically generate CNC code based on readable image formats such as *. jpg, *. gif, *. bmp, *. pcd, *. tif, and make use of machine tool for CNC machining. This system first vectorizes an image by using preprocessing such as smooth processing, edge detection, and contour tracking, and converts it into CNC code, then generates a program that can be identified by PMAC, and drives machine tool to process CNC machining. At last, an example proves the validity of this method.

Developing postprocessor for five-axes milling machines with dual rotary head

Five axis milling technology has been in use nearly 25 years in VTI Belgrade. Primarily it is used in the production process of wind tunnel models. For generating tool path and the post-processing paths, used postprocessor generated on Siemens PLM NX. Producer of CAD/CAM software, in newer versions, the old concept of post processing GPM (Graphics Postprocessor Module) replaced it with a new, improved, module MOM (Manufacturing Output Manager). The VTI are identified in the CNC code for five axes milling, generated using the MOM module, some errors. Product support application engineer confirmed all the allegations VTI. This was the reason for the development of its own postprocessor for five axes milling machines with double rotating head. The paper gives a detailed overview of the development based on the kinematic model of the five-axes milling machine in VTI Belgrade.

Automatic Programming Based on the Feature of the Parts

The structure of machining workpiece is more and more complex, from the perspective of CNC machining, contains a lot of processing features generally. Machining feature plays an important role for production process for CNC machining programming, CNC code, as well as the analysis of clamping. Feature programming is one of the development trend of automatic CNC programming. This improve the efficiency of programming greatly.

The Research on Edged Detecting in CNC Engraving Technology Based on Reverse Engineering

Currently, the ancient calligraphy and painting are widely used in decoration screen; however, the processing technic is normally based on manual manipulation. Normally, this kind of processing is not efficient, and with highly cost. In addition, it could not maintain the original artistic style in maximum. the paper proposes to process the sculpture of ancient calligraphy according to its photo, by adopting the CNC technology based on reverse engineering method, which enables to mostly keep the original artistic style, and to create the CNC code automatically with the assistant of image processing to achieve intelligent machining.

A New Numerical Control System Based on ARM Microprocessor

In this paper, a new numerical control system for machining tool is introduced. The system hardware’s basis is ARM9 microprocessor. It can control four step-servo motors or servo-actuators and realize any three motors motion simultaneously. The system is a multifunction. To realize this, the software is important. The system’s software analyzes the keyboard response, translates the CNC code, receive the CNC code from other computer or keyboard. It gives the interpolation values made the system realize circle or straight line movement. In the management of software, the system can realize multifunction tasks