Numerical Controlled Milling Machine Research Articles

Patient-specific needle guidance templates drilled intraprocedurally for image guided intervention: feasibility study in swine.

Thermal ablation of large tumors may benefit from simultaneous placement of multiple needles, but accurate placement becomes challenging as the number of needles increases. The aim of this work was to evaluate use of personalized needle guidance grid templates based on intraprocedural CT and fabricated at the point of care to implement ablation treatment plans with multiple needles in vivo. A plastic frame was designed to hold two parallel plastic guide plates in a rigid relationship, fixed over the abdomen by a mounting arm. Steel ball targets (1.5mm) were implanted under ultrasound in the livers of two domestic swine under general anesthesia. Following breath-hold CT of the subject and frame, the targets and frame were identified using customized 3D Slicer-based planning software. Multiple needle trajectories targeting the balls were planned, including complex off-plane trajectories. A machining program for drilling the hole pattern corresponding to the planned needle trajectories was generated. The pattern was drilled in the two plates with a numerical-controlled milling machine in the suite. The plates were attached to the frame and needles passed through the paired holes to the calculated depth. Placement accuracy was defined as needle tip-to-target distance on post-placement CT. The planning process and manufacturing required approximately 6 and 15min, respectively. Needles were rapidly inserted (n = 11) to the target points without complications or traversing nontarget anatomy. The mean needle tip-to-target distance error was 3.4 ± 2.2, range 0-7mm. Rapid and accurate needle placement was feasible using a subject-specific, custom-drilled, needle guidance grid template fabricated intraprocedurally. Targeting accuracy and performance were similar to more complex and expensive tracking systems which may enable accurate intraprocedural implementation of treatment plans in the liver or other organs. This may be of value in complex ablation cases or in areas where more advanced guidance systems are not available.

Experimental Investigation of Face Milling Surface Study on AA1100 by Using VMC

Abstract: Aluminum alloys are extensively used as a main engineering material in various industries such as automotive industries, the mould and die components manufacture and the industry in which weight is the most important factor. Surface roughness is an important measurement of product quality since it greatly influences the performance of mechanical parts as well as production cost. The purpose of this research was to investigate the effect of the main factors of the surface roughness in aluminum semi-solid AA1100 face milling. The results of the research could be applied in the manufacture of automotive components and mold industries. This study was conducted by using computer numerical controlled milling machine with 40- millimeter diameters fine type carbide tool with twin cutting edge. The experimental results were evaluated using Taguchi technique. Machining timing, and Flatness were mainly influenced with feed. MRR was mainly influenced with DOC. Practically minimum flatness error obtained at low speed with maximum feed and depth of cut. During this operation very low surface finish 0.520 µm generally it can achieve cylindrical grinding process. Keywords: AA 1100, face milling, Ra, CMM, flatness error

Enhancing surface characteristics of additively manufactured fiber reinforced thermoplastic mold using thermoset coating with ceramic particles

A commercially available thermoset polymer liquid coating reinforced with ceramic particles was applied on the surface of an additively manufactured carbon fiber reinforced thermoplastic composites to improve its surface characteristics for composite mold application. The mold demonstrated herein was fabricated via material extrusion additive manufacturing (MEAM) and served for the fabrication of autoclave-cured laminated composite structures. Test specimens used in this investigation were additively manufactured with Polyphenylene Sulfide (PPS) reinforced with 50% by weight of carbon fiber. Following the printing process, the surface of the specimens was finished in a numerical controlled milling machine. The effect of machining parameters such as the surface speed and the chip load on the surface roughness was investigated. The machining parameters that yielded the lowest surface roughness were used to machine the specimens used in this work. Following machining, an approximately 10 μm thick coating based on a thermoset resin reinforced with ceramic particles was applied on the surface of flat specimens via the liquid spray coating technique and cured at elevated temperature. Surface characteristics relevant to molds used in composite manufacturing such as surface roughness, abrasion resistance , hardness, friction, and vacuum integrity were assessed for the coated and noncoated specimens. The results showed that the coating decreased the abrasion wear index by about 89%, decreased the vacuum loss by about 95%, and lowered the static and kinetic friction by about 40% and 38%, respectively, compared to the non-coated printed material. However, the coated surface did not improve hardness nor roughness of the surface. • Thermoset liquid polymer coating with ceramic particle was applied to additively manufactured fiber reinforced composite. • The abrasion resistance of the additively manufactured carbon fiber reinforced composite was significantly increased with the coating. • The polymer coating did not improve surface hardness and roughness of the additively manufactured carbon fiber reinforced composite. • The coating provided lower static and kinetic surface friction coefficient compared to the non-coated surface of the composite. • Vacuum integrity of the additively manufactured fiber reinforced composite surface was significantly improved with the coating.

Internet of Things Based Cutting Tool Status Monitoring in a Computer Numerical Control Milling Machine

The Internet of Things (IoT) in the manufacturing industry shares machine data in real time. The majority of industrial data can be gathered and processed from machines and other remote IoT devices in a production system through data streaming. As sensors become smaller and more affordable, the Internet of things will attract more attention. It is possible to employ a wide range of sensors for monitoring, and with efficient open-source software, the status of the operation can be evaluated effectively. Our work aims at providing instructions for sending data (cutting tool status time) from Particle Photon devices connected to CNC milling machines to open-source software called ThingSpeak. This task is accomplished by integrating the Particle Photon device with the infrared sensor to the CNC milling machine. Three axis CNC vertical milling machine is used to manufacture the sample component. The status of the cutting tool, in this case the cutting time for each machining feature is monitored. Using infrared technology, the sensor detects whether the cutting tool is present. Particle photons measure machining time and communicate it to ThingSpeak. The ThingSpeak library will interpret the cloud information and displays it. With ThingSpeak software, we define the fields for various cutting tools and track every tool in real time. The time recorded using ThingSpeak software is found to be near to the time, which is monitored manually by the user. A major step in computer assisted process planning in manufacturing is monitoring the machining time for each cutting tool and it is successfully implemented in this research work.

STEP-NC Compliant Intelligent CNC Milling Machine with an Open Architecture Controller

A STEP-NC or ISO 14649 compliant machine controller is developed, using Open Architecture Control technology for a three-axis Computer Numerical Control milling machine in this research. The controller is developed on a Raspberry Pi single-board computer, using C++ language. This new development is proposed as a low-cost alternative to ISO6983 standard, ensuring continuous integration in the CAD/CAM/CNC chain in machining; thus, it broadens the spectrum of problems handled by conventional CNC systems. The new machine controller is intelligent enough to extract geometrical and manufacturing parameters, cutting tool data, and material data from the STEP-NC file. Accordingly, tool paths for machining can be generated in the controller itself. The shop floor level modification of parameters and the possibility of regeneration of new toolpaths is an added advantage of this new controller. The modified or improved version of the STEP-NC file can be sent back to the CAD/CAM system to close the CAD/CAM/CNC chain. Machine condition monitoring can be achieved by connecting sensors through an available slave I/O board. In the present development, the current drawn by each servo motor is fed back to the controller for cutting condition monitoring. A laboratory scale three-axis CNC milling machine is developed to test the performance of the newly developed controller. The accuracy of positioning, perpendicularity of axes and linearity of this machine are experimentally verified through standard tests. The STEP-NC compliance of the controller is tested and verified, using a STEP-NC program derived based on a sample program given in ISO 14649 standard.

Simulation In Classroom: Development Mini Computer Numerical Control (CNC) Milling Machine for G Code Movement

Simulation In Classroom: Development Mini Computer Numerical Control (CNC) Milling Machine for G Code Movement

A General Empirical Energy Consumption Model for Computer Numerical Control Milling Machine

Energy consumption of computer numerical control (CNC) machines is significant and various empirical models have been developed to model the specific energy consumption (SEC) of CNC machines. However, most of the models are developed for specific machines and hence have limited applications in manufacturing industry. In this research, a general empirical SEC model for milling machine at certain power level is developed based on actual cutting experimental data. In this model, stand-by power and spindle power are used in the SEC model for the first time. The material removal rate (MRR) is used to represent the cutting parameter. The proposed model is fitted by the regression analysis and validated using experimental data. Results show that the proposed model can be applied on various milling machines with an average absolute residual ratio of 6%. The model is also validated through a series of cutting experiments on a machine center, with an accuracy of 91.5%, for the SEC calculation.

Research on the mechanism of milling surface waviness formation in thin-walled blades

The surface waviness of blade surfaces in numerically controlled (NC) milling processes directly affects the mechanical behavior of the blade. To research the mechanism of surface waviness formation, this study utilizes wavelet analysis in investigating the measured results of surface profile. Firstly, the experiment on a #45 steel cantilever blade was performed on an NC milling machine and the vibrational signals during the milling process were analyzed by fast Fourier transform. Secondly, the first-order natural frequencies of the machine-tool system and the machine-workpiece system were obtained by modal test based on DWESOFT and simulation based on ANSYS. Thirdly, the selected optimal wavelet was applied to decompose and reconstruct each layer of the blade surface contour signal based on MATLAB. Finally, the frequency information of the wavelet, the frequency information of the milling vibration signals, and the first-order natural frequencies of the systems were compared. The maximum of the amplitude value of the milling vibration signals corresponds to the frequency 161.1 Hz, which is equivalent to the excitation frequency of the teeth by calculating and the frequency of the maximum amplitude of the second-layer profile by wavelet analysis. The modal analysis showed that the first-order natural frequencies of the machine-tool system in the x and y directions and the machine-workpiece system are 737.3, 668.9, and 542.0 Hz, respectively, which are far away from the frequencies the maximum amplitude of the each layer profile obtained by wavelet analysis. The results showed that surface waviness is caused by forced vibration in thin-blade NC milling, rather than self-excited vibration.

Double-layered timber plate shell

This article presents a new lightweight construction system for doubly curved shells made from timber plates, inspired by the masonry vaults of Eladio Dieste. The system was developed for a specific case-study project, and general applications to other freeform surfaces are being discussed. The shells are built from two interconnected layers of structural wood veneer plates, using integral through-tenon joints for a fast, precise, and simple assembly. This allows for the construction of a series of differently shaped vaults without a costly mold or support structure. Instead, inclined joints cut with a 5-axis computer numerical controlled milling machine embed the correct location and angle between plates into the shape of the parts. This constrains the relative motions between joined parts to one assembly path. To take advantage of the benefits of such connectors, the constrained assembly paths must be considered in the fundamental design of the system, allowing for the insertion of each plate. This imposes additional constraints in the segmentation process of doubly curved shells. In order to meet the requirements and resolve the multi-constraint system, we use a global, nonlinear optimization approach. Developed as a close collaboration between architects, computer scientists and structural engineers, this article includes an experimental analysis of the influence of parametric modifications in the shape of connectors on their load-bearing performance.

The Effect of Surface Finish on Sculptured Shape Utilizing Scanned Data – Reversed Engineering (CATIA V5 & DELCAM)

The ultimate aim of this study was to investigate the effect of surface finish for a machined part which was programmed by two popular CAD/CAM software namely Catia V5 and Delcam using scanned data obtained from one of the Reverse Engineering methods namely Three-Dimensional (3D) scanning process. A gaming mouse was chosen as the physical part to be scanned and machined because of its sculptured shape and wavy looks. In this study, simultaneous three-axis machining programs were created and machined using three-axis Computer Numerical Control (CNC) Milling machine. Initially, the physical gaming mouse gone through the first process called scanning process using a 3D scanner; model 700 CX in order to capture the 3D CAD data in points cloud form. The raw scanning data then gone through editing process to obtain better surfaces. Moreover, the stable and edited CAD model then undergone CAD/CAM programming process for both mentioned software respectively. There were ten random points chosen to be analyzed for the surface roughness analysis. The arithmetic mean value (Ra) was used as the roughness value reference. The results reveal that the average surface roughness for the ten points was 0.232 μm for Catia V5 whilst for Delcam was around 0.274 μm. Ultimately, Catia V5 producing better surface finish compared to Delcam software concluded from the analysis carried out as presented in this paper.

Implementing a Preventive Maintenance Planning Model for Computer Numerical Control (CNC) Milling Machine

Preventive maintenance is early access or pre-planned maintenance of the problems occur in any machinery units and it has become the important part of today’s industry to avoid breakdown as it can save costly faults, keep Continues production with standardize machinery, reduce waste and also important for safety of deployment. The paper describes the way to avoid breakdown in CNC’s by using time based scheduled preventive maintenance for different parameters, while taking 20 CNC machines under observation. PM sheet of CNC’s is divided into parts over time for different parameters like chuck pressure inspection is kept in daily basis list while ATC Arm in 4 month check list. Some parameters set on the basis of theoretical studies of material fatigue life and some on experimental basis in the resultant sheet. The developed sheet could help manufacturers to figure out the problems in CNC’s on their usage over time range, simply the sheet can be taken as survey of performance of CNC’s. Also a proper planed PM sheet can save a valuable amount of money on maintenance.

An investigation on the surface finish of sculptured surface utilizing reverse engineering data of crank case cover – (CATIA V5 & DELCAM)

The ultimate aim of this study was to investigate the effect of surface finish for a machined part which was programmed by two popular Computer Aided Design / Computer Aided Manufacturing (CAD/CAM) software namely as Catia V5 and Delcam (Delcam for Solidworks - DFS) by using scanned data obtained from one of the Reverse Engineering methods namely Three-Dimensional (3D) scanning process. A crank case cover was chosen as the physical part to be scanned and machined because of its sculptured shape and complex geometry. In this study, simultaneous three-axis machining programs were created and machined using threeaxis Computer Numerical Control (CNC) Milling machine; DMC 635 Ecoline. Furthermore, all machining parameters are remained the same for both programs. Initially, the physical crank case cover gone through the first process called scanning process using a 3D scanner; model 700 CX in order to capture the 3D CAD data in points cloud form. The raw scanned data then gone through editing process to obtain better surfaces using Geomagic Studio software. Moreover, the stable and edited CAD model then undergone CAD/CAM programming process for both mentioned software respectively. On the other hand, there were seven random points chosen to be analyzed for the surface roughness analysis. The arithmetic mean value (Ra) was used as the roughness value reference using Mitutoyo Surface Tester. Ultimately, it could be concluded that Catia V5 producing better surface finish compared to Delcam software concluded from the analysis carried out as presented in this paper.

Diagnostics and Control of Ceramic Tools During High-Speed Milling of Tempered Steels on CNC Machine Tools

The operating principles of an algorithm for integrated diagnostics and control of ceramic tools during milling of tempered steel are discussed. The algorithm for detection of wear of the tool is based on the use of force parameters and chipping is identified from vibro-acoustic signals. The generalized structure of the subsystem for diagnostics and control of the state of a ceramic tool in a computer numerical controlled milling machine is described.

An online damage identification approach for numerical control machine tools based on data fusion using vibration signals

In this paper, a new approach is proposed based on data fusing with vibration signals using time-frequency parameters, probabilistic principal component analysis (PPCA) and statistical inference, for improving the accuracy and visibility of damage identification for numerical control (NC) machine tools. Time-frequency feature principal components are put forward, which extracted from eight dimensionless parameters statistically in the time and frequency domains by PPCA. The Chi-2 statistic is established according to statistical inference principle, and the feature figure of principal components is built that can acquire damage distribution of tools by measured data. An empirical analysis in NC milling machine tools is developed, and the result shows high accuracy and visibility of the proposed approach.

Research and Application of Numerical Control Milling Machine Tool Length Compensation Instructions

the numerical control milling process that commonly use tool length compensation function instruction, correct and reasonable use of tool length compensation function instruction can improve efficiency and machining accuracy. This article mainly studies the three methods of application of tool length compensation function instruction, which can provide a reference for correct application of tool length compensation function instruction.

An Investigation of Optimum Cutting Conditions in Face Milling Semi-Solid Cast 6061 Aluminum Alloy Using Carbide Tool

The purpose of this research was to investigate the effect of the main factors of the surface roughness in semi-solid 6061 aluminum face milling. This study was conducted by using computer numerical controlled milling machine. The controlled factors were the speed, the feed rate and the depth of cut which the depth of cut was not over 1 mm. For this experiment, we used factorial designs and the result showed that the factors effected of surface roughness was the feed rate and the speed while the depth of cut did not effect with the surface roughness. Furthermore, the surface roughness was likely to reduce when the speed was 4,200 rpm and the feed rates was 1,300 mm/min. The result of the research led to the linear equation measurement value which was Ra = 0.186 - 0.000034 Speed + 0.000047 Feed rate. The equation formula should be used with the speed in the range of 3,200-4,200 rpm, feed rate in the range of 1,300-1,800 mm/min and the depth of cut not over 1 mm. The equation was used to confirm the research results, it was found that the mean absolute percentage error of the surface roughness obtained from the predictive comparing to the value of the experiment was 4.12%, which was less than the specified error and it was acceptable.

Computer-aided orbital wall defects treatment by individual design ultrahigh molecular weight polyethylene implants

Despite of well-known advantages of high molecular weight polyethylene (Medpor, Synpore) in orbital reconstructions, the thickness of those implants significantly exceeds 0.5 mm and precise modification of thickness is limited. The aim of this study was to present the application of a selfdeveloped method of treatment orbital wall fracture by custom implant made of ultrahigh molecular weight polyethylene (UHMW-PE). Material and methodFirst, the test of influence of sterilization process upon implant deformation was performed (autoclaving, ethylene oxide, gas plasma, irradiation). Next, ten cases for delayed surgical treatment of orbital fracture were included into this study (7 males, 3 females). Based on CT scan and mirrored technique, a CAD model of virtual implant for repairing orbital wall was made. Then, an implant was manufactured with a computer numerical controlled milling machine from UHMW-PE block, sterilized and used during a surgical procedure. Clinically used implants had thickness from 0.2 to 4.0 mm. ResultsThe best method of sterilization is ethylene oxide process, and the worst is autoclaving. In this series of delayed surgical cases, functional results of orbital surgery are worse than in simpler, early treated cases, but long-term subsidence of diplopia is noticeable [10% poor results]. The results of the treatment depend on the initial level of diplopia where severe initial diplopia to be corrected requires thicker implants (p < 0.01). It also leads to longer surgical procedures (p < 0.01), but prolongation of the surgery had no negative influence upon results of any investigated follow-up examinations. Obviously, the orbital destruction intensity is related to injury-evoked initial diplopia but it also influences whole results of treatment up to 12 months post-op. Interesting result is presented by the relation of maximal implant thickness to 12-month diplopia evaluation. Thicker implants used result in lower residual diplopia (p < 0.05). This is important because of the correlation between the higher orbital destruction intensity with a thicker UHMW-PE implant (p < 0.05) applied in this series. ConclusionPatient-specific ultrahigh molecular weight polyethylene implants enable precise reconstructions of orbital wall. One should not be afraid of a significant eye globe reposition caused by these thickness modulated implants, as such repositioning is essential for an efficient correction of enophthalmos.

An Investigation of Optimum Cutting Conditions in Face Milling Aluminum Semi Solid 2024 Using Carbide Tool

The purpose of this research was to investigate the effect of the main factors of the surface roughness in aluminum semi-solid 2024 face milling. The results of the research could be applied in the manufacture of automotive components and mold industries. This study was conducted by using computer numerical controlled milling machine with 63 millimeter diameters fine type carbide tool with twin cutting edge. The controlled factors were the speed, the feed rate and the depth of cut which the depth of cut was not over 1mm. For this experiment, we used factorial designs and the result showed that the factors effected of surface roughness was the feed rate and the speed while the depth of cut did not effect with the surface roughness. Furthermore, the surface roughness was likely to reduce when the speed was 3,600rpm and the feed rates was 1,000mm/min. The result of the research led to the linear equation measurement value which was Ra = 0.205 - 0.000022 Speed + 0.000031 Feed rate. The equation formula should be used with the speed in the range of 2,400 - 3,600rpm, feed rate in the range of 1,000 - 1,500mm/min and the depth of cut not over 1mm. The equation was used to confirm the research results, it was found that the mean absolute percentage error (MAPE) of the surface roughness obtained from the predictive comparing to the value of the experiment was 3.48%, which was less than the specified error and it was acceptable.

The Study of Proper Conditions in Face Milling Palmyra Palm Wood and Coconut Wood Using Design of Experiment

The purpose of this research was to investigate the effects of main factors on the surface roughness in face milling process palmyra palm wood and coconut wood by computer numerical controlled milling machine and using shell end mill cutting tools 6 edges. The main factors including speed, feed rate, depth of cut and angle of cut were investigated for the optimum surface roughness. The result of preliminary trial showed that the depth of cut and the angle of the cut had no effect on surface roughness. It was found from the experiment that the factors affecting surface roughness were feed and speed, with tendency for reduction of roughness value at a lower feed rate and greater cutting speed. Therefore, in the facing process for palmyra palm wood it was possible to determine a face milling condition by means of the equation Ra = 0.954 + 20.4 Feed + 0.00126 Speed. This equation was employed at a limited speed of 800-1200 rpm, and the feed rate of 0.03-0.05 mm/tooth. The result from the experiment of the mean absolute percentage error of the equation of surface roughness is 6.10% which is less than the margin of error, and is acceptable. For coconut wood it was found from the experiment that the factor affecting surface roughness was feed rate and cutting speed, with tendency for reduction of roughness value at lower feed rate and greater cutting speed. Therefore, in the face milling coconut wood it was possible determine a facing condition by means of the equation Ra = 4.72 - 0.000864 Speed + 0.00443 Feed. Leading this equation goes to use is in limitation cutting speed 1000-2000 rpm at feed rate 100-300 mm/min. The result from the experiment of mean absolute percentage error of the equation of surface roughness is 4.64% which is less than the margin of error, and is acceptable. As a result, the selection of optimal machining parameters can be greatly benefited to the Coconut wood furniture manufacturing industry in terms of productivity improvement.

Analysis and estimation of energy consumption for numerical control machining

Understanding and estimating the energy consumed by machining are essential tasks as the energy consumption during machining is responsible for a substantial part of the environmental burden in manufacturing industry. Facing the problem, the present paper aims to analyse the correlation between numerical control (NC) codes and energy-consuming components of machine tools, and to propose a practical method for estimating the energy consumption of NC machining. Each energy-consuming component is respectively estimated by considering its power characteristics and the parameters extracted from the NC codes, and then the procedure estimating energy consumption is developed by accounting for the total energy consumption of the components via the NC program. The developed method is verified by comparing the estimated energy consumption with the actual measurement results of machining two test workpieces on two different machine tools, an NC milling machine and an NC lathe, and is also applied to evaluate the energy consumption of two different NC programs on the NC milling machine. The results obtained show that the method is efficient and practical, and can help process planning designers make robust decisions in choosing an effective energy-efficient NC program.