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Machine Vision Based Fish Cutting Point Prediction for Target Weight
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作者 Yonghun Jang Yeong-Seok Seo 《Computers, Materials & Continua》 SCIE EI 2023年第4期2247-2263,共17页
Food processing companies pursue the distribution of ingredientsthat were packaged according to a certain weight. Particularly, foods like fishare highly demanded and supplied. However, despite the high quantity offis... Food processing companies pursue the distribution of ingredientsthat were packaged according to a certain weight. Particularly, foods like fishare highly demanded and supplied. However, despite the high quantity offish to be supplied, most seafood processing companies have yet to installautomation equipment. Such absence of automation equipment for seafoodprocessing incurs a considerable cost regarding labor force, economy, andtime. Moreover, workers responsible for fish processing are exposed to risksbecause fish processing tasks require the use of dangerous tools, such aspower saws or knives. To solve these problems observed in the fish processingfield, this study proposed a fish cutting point prediction method based onAI machine vision and target weight. The proposed method performs threedimensional(3D) modeling of a fish’s form based on image processing techniquesand partitioned random sample consensus (RANSAC) and extracts 3Dfeature information. Then, it generates a neural network model for predictingfish cutting points according to the target weight by performing machinelearning of the extracted 3D feature information and measured weight information.This study allows for the direct cutting of fish based on cutting pointspredicted by the proposed method. Subsequently, we compared the measuredweight of the cut pieces with the target weight. The comparison result verifiedthat the proposed method showed a mean error rate of approximately 3%. 展开更多
关键词 machine vision fish cutting weight prediction artificial intelligence deep learning image processing
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METHOD FOR SUPPRESSING CUTTING CHATTER IN NUMERICAL CONTROL MACHINE TOOLS
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作者 孙宝寿 黄筱调 +3 位作者 顾伯勤 方成刚 丁文政 魏韬 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期108-114,共7页
A new method for suppressing cutting chatter is studied by adjusting servo parameters of the numerical control (NC) machine tool and controlling the limited cutting width. A model of the cutting system of the NC mac... A new method for suppressing cutting chatter is studied by adjusting servo parameters of the numerical control (NC) machine tool and controlling the limited cutting width. A model of the cutting system of the NC machine tool is established. It includes the mechanical system, the servo system and the cutting chatter system. Interactions between every two systems are shown in the model. The cutting system stability is simulated and relation curves between the limited cutting width and servo system parameters are described in the experiment. Simulation and experimental results show that there is a mapping relation between the limited cutting width and servo parameters of the NC machine tool, and the method is applicable and credible to suppress chatter. 展开更多
关键词 numerical control machine tool chatter servo parameter limited cutting width
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Design and Accuracy Analysis of a Metamorphic CNC Flame Cutting Machine for Ship Manufacturing 被引量:3
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作者 HU Shenghai ZHANG Manhui +2 位作者 ZHANG Baoping CHEN Xi YU Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第5期930-943,共14页
The current research of processing large size fabrication holes on complex spatial curved surface mainly focuses on the CNC flame cutting machines design for ship hull of ship manufacturing. However, the existing mach... The current research of processing large size fabrication holes on complex spatial curved surface mainly focuses on the CNC flame cutting machines design for ship hull of ship manufacturing. However, the existing machines cannot meet the continuous cutting requirements with variable pass conditions through their fixed configuration, and cannot realize high-precision processing as the accuracy theory is not studied adequately. This paper deals with structure design and accuracy prediction technology of novel machine tools for solving the problem of continuous and high-precision cutting. The needed variable trajectory and variable pose kinematic characteristics of non-contact cutting tool are figured out and a metamorphic CNC flame cutting machine designed through metamorphic principle is presented. To analyze kinematic accuracy of the machine, models of joint clearances, manufacturing tolerances and errors in the input variables and error models considering the combined effects are derived based on screw theory after establishing ideal kinematic models. Numerical simulations, processing experiment and trajectory tracking experiment are conducted relative to an eccentric hole with bevels on cylindrical surface respectively. The results of cutting pass contour and kinematic error interval which the position error is from -0.975 mm to +0.628 mm and orientation error is from -0.01 rad to +0.01 rad indicate that the developed machine can complete cutting process continuously and effectively, and the established kinematic error models are effective although the interval is within a 'large' range. It also shows the matching property between metamorphic principle and variable working tasks, and the mapping correlation between original designing parameters and kinematic errors of machines. This research develops a metamorphic CNC flame cutting machine and establishes kinematic error models for accuracy analysis of machine tools. 展开更多
关键词 CNC cutting machine metamorphic principle accuracy analysis screw theory error model
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Hardening Effect on Machined Surface for Precise Hard Cutting Process with Consideration of Tool Wear 被引量:3
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作者 YUE Caixu LIU Xianli +3 位作者 MA Jing LIU Zhaojing LIU Fei YANG Yongheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1249-1256,共8页
During hard cutting process there is severe thermodynamic coupling effect between cutting tool and workpiece, which causes quenching effect on finished surfaces under certain conditions. However, material phase transf... During hard cutting process there is severe thermodynamic coupling effect between cutting tool and workpiece, which causes quenching effect on finished surfaces under certain conditions. However, material phase transformation mechanism of heat treatment in cutting process is different from the one in traditional process, which leads to changes of the formation mechanism of damaged layer on machined workpiece surface. This paper researches on the generation mechanism of damaged layer on machined surface in the process of PCBN tool hard cutting hardened steel Cr12MoV. Rules of temperature change on machined surface and subsurface are got by means of finite element simulation. In phase transformation temperature experiments rapid transformation instrument is employed, and the effect of quenching under cutting conditions on generation of damaged layer is revealed. Based on that, the phase transformation points of temperature under cutting conditions are determined. By experiment, the effects of cutting speed and tool wear on white layer thickness in damaged layer are revealed. The temperature distribution law of third deformation zone is got by establishing the numerical prediction model, and thickness of white layer in damaged layer is predicted, taking the tool wear effect into consideration. The experimental results show that the model prediction is accurate, and the establishment of prediction model provides a reference for wise selection of parameters in precise hard cutting process. For the machining process with high demanding on surface integrity, the generation of damaged layer on machined surface can be controlled precisely by using the prediction model. 展开更多
关键词 precise hard cutting hardened mould steel hardening effect damaged layer on machined surface tool wear
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Optimum cutting speed of block-cutting machines in natural stones for energy saving 被引量:3
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作者 N.Bilim 《Journal of Central South University》 SCIE EI CAS 2012年第5期1234-1239,共6页
Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of ma... Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of major importance in the natural stone-processing industry. An experimental study was carried out utilizing a fully instrumented block-cutter to investigate the sawing performances of five different types of travertine blocks during cutting with a circular diamond saw. The sawing tests were performed in the down-cutting mode. Performance measurements were determined by measuring the cutting speed and energy consumption. Then, specific energy was determined. The one main cutting parameter, cutting speed, was varied in the investigation of optimum cutting performance. Furthermore, some physico-mechanical properties of file travertine blocks were determined in the laboratory. As a result, it is found that the energy consumption (specific energy) of block cutting machines is highly affected by cutting speed. It is determined that specific energy value usually decreases when cutting speed increases. When the cutting speed is higher than the determined value, the diamond saw can become stuck in the travertine block; this situation can be a problem for the block-cutting machine. As a result, the optimum cutting speed obtained for the travertine mines examined is approximately 1.5-2.0 m/min. 展开更多
关键词 cutting speed TRAVERTINE block cutting machine specific energy natural stone energy saving
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CUTTING REGULARITY AND DISCHARGE CHARACTERISTICS BY USING COMPOSITE COOLING LIQUID IN WIRE CUT ELECTRICAL DISCHARGE MACHINE WITH HIGH WIRE TRAVELING SPEED 被引量:11
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作者 LIU Zhidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第5期41-45,共5页
The analysis of cutting regularity is provided through using and comparing two typical cooling liquids. It is proved that cutting regularity is greatly affected by cooling liquid's washing ability. Discharge characte... The analysis of cutting regularity is provided through using and comparing two typical cooling liquids. It is proved that cutting regularity is greatly affected by cooling liquid's washing ability. Discharge characteristics and theoretic analysis between two electrodes are also discussed based on discharge waveform. By using composite cooling liquid which has strong washing ability, the efficiency in the first stable cutting phase has reached more than 200 mm^2/min, and the roughness of the surface has reached Ra〈0.8 μm after the fourth cutting with more than 50 mm^2/min average cutting efficiency. It is pointed out that cutting situation of the wire cut electrical discharge machine with high wire traveling speed (HSWEDM) is better than the wire cut electrical discharge machine with low wire traveling speed (LSWEDM) in the condition of improving the cooling liquid washing ability. The machining indices of HSWEDM will be increased remarkably by using the composite cooling liquid. 展开更多
关键词 Wire cut electrical discharge machine with high wire traveling speed Composite cooling liquid Discharge characteristic cutting regularity
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Study on full automatic arc welding machine for spherical tank 被引量:2
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作者 蒋力培 张甲英 俞建荣 《China Welding》 EI CAS 2002年第1期34-37,共4页
A full automatic welding machine for spherical tanks' all position multi layer welds has been developed. This machine is mainly composed of a two dimension seam tracking system based on microcomputer's memor... A full automatic welding machine for spherical tanks' all position multi layer welds has been developed. This machine is mainly composed of a two dimension seam tracking system based on microcomputer's memory and a welding tractor as well as rail. The main features of the machine are: while welding the first layer of a seam, its microcomputer system can analyze and store the tracing information from a two dimension sensor, and control the welding head device to realize two dimension real time tracing; while welding the second layer up to the top layer of the seam, it can realize two dimension tracing based on the memorial data, automatically determine the layer number and continually sway the welding head. The welding test shows that the machine has good tracing and welding behavior, and is suitable for spherical tank's all position multi layer welds. 展开更多
关键词 full automatic welding machine spherical tank memorial tracing all position welding
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Research on key control technologies of all-position automatic welding machine 被引量:1
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作者 曾惠林 杜则裕 +1 位作者 马静 黄福祥 《China Welding》 EI CAS 2009年第3期69-73,共5页
The pipeline all-position automatic welding machine system is a special welding system for automatically welding circumferential joint of pipeline on site, which has been widely used to the long-distance pipeline cons... The pipeline all-position automatic welding machine system is a special welding system for automatically welding circumferential joint of pipeline on site, which has been widely used to the long-distance pipeline construction projects due to the advantages of automatic control for welding parameters at all-position, moving speed of bugs and operating. In this paper, the key control technologies of PAWM all-position automatic welding machine ( developed by Pipeline Research Institute of CNPC) such us the automatic control system, control software, personal digital assistant (PDA) software and complex programmable logic device ( CPLD ) program as well us the control method of welding parameter have been described detailedly. With the higher welding quality, higher welding effwiency and lower labor intensity, PA WM all-position automatic welding machine has been successfully applied in many famous pipeline construction projects. 展开更多
关键词 key control technology ALL-POSITION automatic welding machine welding parameters
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Digital controlling for GMA welding machine based on DSP 被引量:1
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作者 华学明 吴毅雄 +2 位作者 张勇 焦馥杰 于乾波 《China Welding》 EI CAS 2003年第2期158-161,共4页
This paper introduced a welding machine for GMAW using digital controlling method based on DSP (Digital Signal Process). By means of flexible programming according to welding technologies and experiences the suitable ... This paper introduced a welding machine for GMAW using digital controlling method based on DSP (Digital Signal Process). By means of flexible programming according to welding technologies and experiences the suitable characteristics of welding machine, such as line compensation, welding voltage and current feedback, wire-feed driving, SCR trigging and so on, can be controlled and self-adjusted using digital signals. Through the designing based on DSP it is put out that the traditional hardware of control circuit is decreased greatly which can enhance the stability and reliability of welding machine. Finally, the welding experiment using CO 2 shielding gas proves that the welding process is stable. 展开更多
关键词 digital signal process welding machine GMAW
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Deep Cutting Plane Inequalities for Stochastic Non-Preemptive Single Machine Scheduling Problem 被引量:1
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作者 Fei Yang Shengyuan Chen 《American Journal of Operations Research》 2015年第2期69-76,共8页
We study the classical single machine scheduling problem but with uncertainty. A robust optimization model is presented, and an effective deep cut is derived. Numerical experiments show effectiveness of the derived cut.
关键词 Single machine SCHEDULING CUT Generation Robust Optimization
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Cutting and Welding of High-Strength Steels Using Non-Vacuum Electron Beam as a Universal Tool for Material Processing 被引量:1
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作者 Thomas Hassel Nils Murray +1 位作者 Georgii Klimov Alexander Beniyash 《World Journal of Engineering and Technology》 2016年第4期598-607,共11页
Using a non-vacuum electron beam, a two-step process chain for plate materials is a feasible possibility. Cutting and welding can be performed in subsequent steps on the same machine for a highly productive process ch... Using a non-vacuum electron beam, a two-step process chain for plate materials is a feasible possibility. Cutting and welding can be performed in subsequent steps on the same machine for a highly productive process chain. The electron beam is a tool with high energy conversion efficiency, which is largely independent of the type of metal. Its high power density qualifies the non-vacuum electron beam as an outstanding energy source for the well-known NVEB welding as well as for high-speed cutting. Welding is possible with or without filler wire or shielding gas, depending on the application. The NVEB-cutting process employs a co-moving cutting head with a sliding seal for extremely high cutting speeds producing high quality edges. Due to direct removal of fumes and dust, NVEBC with local suction is an exceptionally clean and fast process. The NVEB welding process is possible directly after cutting, without further edge preparation. The potential directions of development of non-vacuum electron beam technologies are discussed. An exemplary two-step process chain using high-strength steel is presented to highlight possible application in industries such as general steel construction, automotive, shipbuilding, railway vehicle or crane construction. An analysis of the mechanical properties of the resulting weld seam is presented. 展开更多
关键词 welding High-Strength Steels Non-Vacuum Electron Beam welding Non-Vacuum Electron Beam cutting
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Joint Performance for Laser Cutting-welding of Zinc-coated Tailored Blanks
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作者 王春明 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第4期46-49,共4页
The process of laser bull welding of zinc-coated steel(SGCD3 and WLZn)blanks was presented.whose edges were prepared by laser cutting.The properties of the butt joints.such as tensile strength.bending,stamping.weld ... The process of laser bull welding of zinc-coated steel(SGCD3 and WLZn)blanks was presented.whose edges were prepared by laser cutting.The properties of the butt joints.such as tensile strength.bending,stamping.weld shape,and corrosion-resisant were tested.The experiments of laser cutting and welding were carried ont on a custom-made system designed.which is a set of equipment for wide sheet butt welding based on a laser cutting-welding combination process.The experiments proved the technological feasibility of laser butt welding for thin zinc coated steel sheets whose edges were prepared by laser cutting on the same equipment. 展开更多
关键词 laser welding tailored blanks zinc coated steel blanks laser cutting
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PENETRATION QUALITY EVALUATION IN ROBOTIZED ARC WELDING BASED ON SUPP0RT VECTOR MACHINE
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作者 YeFeng SongYonglun +1 位作者 LiDi LaiYizong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第4期387-390,共4页
A quality monitoring method by means of support vector machines (SVM) forrobotized gas metal arc welding (GMAW) is introduced. Through the feature extraction of the weldingprocess signal, a SVM classifier is construct... A quality monitoring method by means of support vector machines (SVM) forrobotized gas metal arc welding (GMAW) is introduced. Through the feature extraction of the weldingprocess signal, a SVM classifier is constructed to establish the relationship between the feature ofprocess parameters and the quality of weld penetration. Under the samples obtained from auto partswelding production line, the learning machine with a radial basis function kernel shows goodperformance. And this method can be feasible to identity defect online in welding production. 展开更多
关键词 welding Quality monitoring Support vector machine
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Dynamic modeling of ultra-precision fly cutting machine tool and the effect of ambient vibration on its tool tip response 被引量:1
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作者 Jianguo Ding Yu Chang +4 位作者 Peng Chen Hui Zhuang Yuanyuan Ding Hanjing Lu Yiheng Chen 《International Journal of Extreme Manufacturing》 2020年第2期120-136,共17页
The dynamic performances of an ultra-precision fly cutting machine tool(UFCMT)has a dramatic impact on the quality of ultra-precision machining.In this study,the dynamic model of an UFCMT was established based on the ... The dynamic performances of an ultra-precision fly cutting machine tool(UFCMT)has a dramatic impact on the quality of ultra-precision machining.In this study,the dynamic model of an UFCMT was established based on the transfer matrix method for multibody systems.In particular,the large-span scale flow field mesh model was created;and the variation in linear and angular stiffness of journal and thrust bearings with respect to film thickness was investigated by adopting the dynamic mesh technique.The dynamic model was proven to be valid by comparing the dynamic characteristics of the machine tool obtained by numerical simulation with the experimental results.In addition,the power spectrum density estimation method was adopted to simulate the statistical ambient vibration excitation by processing the ambient vibration signal measured over a long period of time.Applying it to the dynamic model,the dynamic response of the tool tip under ambient vibration was investigated.The results elucidated that the tool tip response was significantly affected by ambient vibration,and the isolation foundation had a good effect on vibration isolation. 展开更多
关键词 ultra-precision fly cutting machine tool transfer matrix method for multibody systems dynamic response of tool tip power spectrum density estimation method ambient vibration
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Implementation Methods of Computer Aided Design-Drawing and Drawing Management for Plate Cutting-Machine 被引量:1
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作者 董玉德 赵韩 谭建荣 《Journal of Donghua University(English Edition)》 EI CAS 2002年第1期115-118,共4页
The implementation methods of computer aided design,drawing and drawing management for plate cuttingmachine are discussed. The system structure for plate cutting- machine design is put forward firstly, then some key t... The implementation methods of computer aided design,drawing and drawing management for plate cuttingmachine are discussed. The system structure for plate cutting- machine design is put forward firstly, then some key technologies and their implementation methods are introduced, which include the structure management of graphics, the unification of graph and design calculation, information share of part, assemble and drawing management system, and movement simulation of key components. 展开更多
关键词 PLATE cutting-machine parametric calculation drawing management MOVEMENT simulation.
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On-line measurement of electrical variables of the transducer during ultrasonic welding and cutting
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作者 闫久春 刘井权 杨士勤 《China Welding》 EI CAS 2002年第2期133-137,共5页
A measurement system for high power electrical variables with ultrasonic frequency was established. It can measure the effective values of the voltage and the current, the active power, the phase difference of voltage... A measurement system for high power electrical variables with ultrasonic frequency was established. It can measure the effective values of the voltage and the current, the active power, the phase difference of voltage and current, the frequency of the transducer during ultrasonic welding and cutting. In sampling circuits of the system, the measured current is sensed by using a no capacitance and no inductance precision resistor and is treated with a difference amplifier, the measured voltage is processed by using a proportional amplifier. For achieving good amplitude frequency characteristics and rapid measurement of high frequency signals, the resistors, capacitors and amplifiers used in the system are rationally selected. Calibrating experiments show that relative errors are less than 1% for voltage and current effective values and less than 2.5% for active power, and absolute errors are ±1 Hz for frequency and ±1.7° for phase difference of voltage and current in the range of 17~23 kHz . 展开更多
关键词 ultrasonic welding ultrasonic cutting on line measurement electrical variables
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Modeling of underwater wet welding seam forming based on support vector machines
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作者 陈波 周利 +1 位作者 杜正勇 冯吉才 《China Welding》 EI CAS 2015年第2期47-51,共5页
Underwater welding is developing fast because of the exploration of marine resources, and underwater wet welding automation is urgently needed because of the rigorous environment. To control the welding process automa... Underwater welding is developing fast because of the exploration of marine resources, and underwater wet welding automation is urgently needed because of the rigorous environment. To control the welding process automatically, the model of the process should first be built to predict the current welding process status. In this paper, arc and visual sensors were used simultaneously to obtain the electrical and visual information of underwater wet welding, and support vector machines (SVM) were used to model the process, experiment results showed that the method could effectively use the information obtained and give precise prediction results. 展开更多
关键词 underwater welding support vector machine welding automation
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Study on intelligent digital welding machine with a self-learning function
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作者 张晓莉 朱强 +2 位作者 李钰桢 龙鹏 薛家祥 《China Welding》 EI CAS 2013年第4期74-80,共7页
A design idea was proposed that it was about intelligent digital welding machine with self-learning and self- regulation functions. The overall design scheme of software and hardware was provided. It was introduced th... A design idea was proposed that it was about intelligent digital welding machine with self-learning and self- regulation functions. The overall design scheme of software and hardware was provided. It was introduced that a parameter self-learning algorithm was based on large-step calibration and partial Newton interpolation. Furthermore, experimental verification was carried out with different welding technologies. The results show that weld bead is pegrect. Therefore, good welding quality and stability are obtained, and intelligent regulation is realized by parameters self-learning. 展开更多
关键词 intelligent digital welding machine SELF-LEARNING large-step calibration
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Case-based intelligent computer aided design system of welding machinery
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作者 林三宝 黎明 吴林 《China Welding》 EI CAS 1998年第1期4-9,共6页
The procedure during complex system plan design of welding position-locating machine is studied in this paper. The main difficulties in designing welding position-locating machine utilizing computer are discussed as w... The procedure during complex system plan design of welding position-locating machine is studied in this paper. The main difficulties in designing welding position-locating machine utilizing computer are discussed as well. A method of case-based intelligent CAD system for welding position-locating machine ( WMICAD) is put forward through wide research on design methodology. Object-oriented programming method is also applied to Ms system. The basic idea and realizing method are described. 展开更多
关键词 welding position-locating machine intelligent computer aided design plan design case-based reasoning
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An automatic arc welding machine for saddle joint seams on large diameter cylinders
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作者 张忠厚 陈基勇 石运伟 《China Welding》 EI CAS 1999年第2期70-75,共6页
This paper deals with the structure, components, characteristics and work principle of a newly developed automatic arc welding machine for saddle joint seams on large diameter cylinders. The equations for designing th... This paper deals with the structure, components, characteristics and work principle of a newly developed automatic arc welding machine for saddle joint seams on large diameter cylinders. The equations for designing the geometry and dimensions of the cam controlling the moving locus of the welding torch have been derived. This welding machine has successfully been used in automatic welding saddle joint seams on boiler drums with good results and low cost. 展开更多
关键词 large diameter cylinders automatic arc welding machine saddle joint seam
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