This study presents a novel method for estimating the surface integrity of end-milled workpieces. It is well known that the mechanical properties of machined surfaces in cutting affect the quality of the final product. In particular, hardness and residual stress often require strict control; however, nondestructive inspection remains a challenge. This study proposes a method to estimate the hardness and residual stress of end-milled surfaces by analyzing cutting forces and images of the tool during machining to obtain approximate temperature and stress distributions. These state quantities are highly correlated with the dislocation density and its distribution on the machined surface, which in turn is strongly correlated with residual stress and surface hardness. Despite this strong correlation, few research studies have been conducted on the topic. In the proposed method, cutting forces, measured by a dynamometer, are analyzed to estimate the specific cutting forces and edge force coefficients. Simultaneously, the flank wear width is recorded using an image-based on-machine measuring device installed in the machine tool. From this information, the average stresses at the primary and tertiary cutting zones are estimated, while the cutting temperature in the primary cutting zone is roughly estimated by considering the traditional shear-angle prediction theory. Using these estimations, hardness and residual stress are calculated based on a simple linear regression model. Parameter identification for the model is performed based on measured hardness and residual stress in end-milling experiments. The model was validated against experimental measurements, which showed that the proposed method can accurately estimate hardness and residual stress, although it was observed that the selection of explanatory variables has a significant effect on accuracy.
{"title":"Estimation of Hardness and Residual Stress on End-Milled Surfaces Using Linear Regression Model","authors":"Hideyuki Fujii, Yukio Takahashi, Jiei Hodohara, Norikazu Suzuki, Yuki Yamada, Yasuhiro Imabeppu, Naruhiro Irino","doi":"10.20965/ijat.2023.p0564","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0564","url":null,"abstract":"This study presents a novel method for estimating the surface integrity of end-milled workpieces. It is well known that the mechanical properties of machined surfaces in cutting affect the quality of the final product. In particular, hardness and residual stress often require strict control; however, nondestructive inspection remains a challenge. This study proposes a method to estimate the hardness and residual stress of end-milled surfaces by analyzing cutting forces and images of the tool during machining to obtain approximate temperature and stress distributions. These state quantities are highly correlated with the dislocation density and its distribution on the machined surface, which in turn is strongly correlated with residual stress and surface hardness. Despite this strong correlation, few research studies have been conducted on the topic. In the proposed method, cutting forces, measured by a dynamometer, are analyzed to estimate the specific cutting forces and edge force coefficients. Simultaneously, the flank wear width is recorded using an image-based on-machine measuring device installed in the machine tool. From this information, the average stresses at the primary and tertiary cutting zones are estimated, while the cutting temperature in the primary cutting zone is roughly estimated by considering the traditional shear-angle prediction theory. Using these estimations, hardness and residual stress are calculated based on a simple linear regression model. Parameter identification for the model is performed based on measured hardness and residual stress in end-milling experiments. The model was validated against experimental measurements, which showed that the proposed method can accurately estimate hardness and residual stress, although it was observed that the selection of explanatory variables has a significant effect on accuracy.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"29 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-05DOI: 10.20965/ijat.2023.p0619
Isamu Nishida, Eiki Yamada, Hidenori Nakatsuji
In this study, we developed a method for automatically generating computer-aided design (CAD) models of injection molding dies. The method only required 3D CAD models of products in the Standard Triangulated Language (STL) format as the input information. We also developed a system for automatically generating numerical control (NC) programs by automating the system process planning necessary for machining the injection molding dies. The method generated CAD models of the injection molding dies by dividing the STL files of the products into triangular meshes on a specified split plane. For injection molding dies with several free curved surfaces, we acquired the tool positions of a ball end mill (as approximated by a spherical shape) and flat drill (as approximated by a cylindrical shape) from the geometrical relationships of the triangles constituting the CAD model. We generated a CAD model of an injection molding die using the proposed method with respect to the CAD model of a product shape to verify the validity of the developed system. Then, we machined the product based on the NC programs and tool position. In addition, we injection molded a product with a machined die to mold it into its original product shape.
{"title":"Automated Process Planning System for Machining Injection Molding Dies Using CAD Models of Product Shapes in STL Format","authors":"Isamu Nishida, Eiki Yamada, Hidenori Nakatsuji","doi":"10.20965/ijat.2023.p0619","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0619","url":null,"abstract":"In this study, we developed a method for automatically generating computer-aided design (CAD) models of injection molding dies. The method only required 3D CAD models of products in the Standard Triangulated Language (STL) format as the input information. We also developed a system for automatically generating numerical control (NC) programs by automating the system process planning necessary for machining the injection molding dies. The method generated CAD models of the injection molding dies by dividing the STL files of the products into triangular meshes on a specified split plane. For injection molding dies with several free curved surfaces, we acquired the tool positions of a ball end mill (as approximated by a spherical shape) and flat drill (as approximated by a cylindrical shape) from the geometrical relationships of the triangles constituting the CAD model. We generated a CAD model of an injection molding die using the proposed method with respect to the CAD model of a product shape to verify the validity of the developed system. Then, we machined the product based on the NC programs and tool position. In addition, we injection molded a product with a machined die to mold it into its original product shape.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"30 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-05DOI: 10.20965/ijat.2023.p0594
Ryosuke Tawara, Chiaki Tanuma, Yutaka Tanaka
Additive manufacturing (AM) technology is extensively applied in various industries, including manufacturing, and is constantly advancing. Compared with subtractive manufacturing methods such as cutting or grinding, the AM is a cost-effective technique with minimal material wastage, and it can produce intricate shapes within a short timeframe. However, research on AM methods involving additional modeling or printing on the surfaces of three-dimensional objects is insufficient. By employing additive modeling, a diverse range of colors and materials can be utilized without requiring support structures, thereby expanding the possibilities of layering-based expression. This study experimentally investigated additive printing systems using a six-degree-of-freedom parallel mechanism stage and a fixed material extrusion head. A slant direct-drive parallel mechanism for a prototype additive printing system was proposed and designed. The developed prototype system enables additional modeling on curved and spherical surfaces of three-dimensional objects. An experimental surface modeling on these objects was conducted. This paper reports on the performance of the motion mechanism, motion range, and positioning accuracy of the modeling stage. Furthermore, the fabricated models were experimentally examined and validated to assess the results of the modeling process.
{"title":"Development of Additive Printing System Using Slant Direct-Drive Parallel Mechanism","authors":"Ryosuke Tawara, Chiaki Tanuma, Yutaka Tanaka","doi":"10.20965/ijat.2023.p0594","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0594","url":null,"abstract":"Additive manufacturing (AM) technology is extensively applied in various industries, including manufacturing, and is constantly advancing. Compared with subtractive manufacturing methods such as cutting or grinding, the AM is a cost-effective technique with minimal material wastage, and it can produce intricate shapes within a short timeframe. However, research on AM methods involving additional modeling or printing on the surfaces of three-dimensional objects is insufficient. By employing additive modeling, a diverse range of colors and materials can be utilized without requiring support structures, thereby expanding the possibilities of layering-based expression. This study experimentally investigated additive printing systems using a six-degree-of-freedom parallel mechanism stage and a fixed material extrusion head. A slant direct-drive parallel mechanism for a prototype additive printing system was proposed and designed. The developed prototype system enables additional modeling on curved and spherical surfaces of three-dimensional objects. An experimental surface modeling on these objects was conducted. This paper reports on the performance of the motion mechanism, motion range, and positioning accuracy of the modeling stage. Furthermore, the fabricated models were experimentally examined and validated to assess the results of the modeling process.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"30 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Owing to recent interest in the production of flexible devices, it is necessary to develop a more convenient approach in which silicon (Si) thin film transistors (TFTs) are fabricated directly onto the flexible substrates at low substrate temperatures. Unfortunately, the physical limitations of conventional plasma-enhanced chemical vapor deposition (PECVD) under low pressures becomes a critical obstacle. In this study, Si film deposition using PECVD under atmospheric pressure excited by very high-frequency electrical power was investigated to overcome this issue. Tetramethylsilane [Si(CH 3 ) 4 ] is used as a source gas that is much safer than silane (SiH 4 ) gas. We investigated the effects of the reactive gas concentration and specific energy (the ratio of input power to unit volume of the reaction gas) on carbon incorporation into the resultant films. Based on the results, we discuss the possibility of forming Si films with sufficiently low carbon content, which is applicable to Si TFTs.
{"title":"Organosilicon-Based Thin Film Formation in Very High-Frequency Plasma Under Atmospheric Pressure","authors":"Afif Hamzens, Kento Kitamura, Shota Mochizuki, Leapheng Uon, Hiromasa Ohmi, Hiroaki Kakiuchi","doi":"10.20965/ijat.2023.p0575","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0575","url":null,"abstract":"Owing to recent interest in the production of flexible devices, it is necessary to develop a more convenient approach in which silicon (Si) thin film transistors (TFTs) are fabricated directly onto the flexible substrates at low substrate temperatures. Unfortunately, the physical limitations of conventional plasma-enhanced chemical vapor deposition (PECVD) under low pressures becomes a critical obstacle. In this study, Si film deposition using PECVD under atmospheric pressure excited by very high-frequency electrical power was investigated to overcome this issue. Tetramethylsilane [Si(CH 3 ) 4 ] is used as a source gas that is much safer than silane (SiH 4 ) gas. We investigated the effects of the reactive gas concentration and specific energy (the ratio of input power to unit volume of the reaction gas) on carbon incorporation into the resultant films. Based on the results, we discuss the possibility of forming Si films with sufficiently low carbon content, which is applicable to Si TFTs.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"30 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electroporation using microstructured electrodes, which generate a localized high electric field, allows molecules (genes) to be introduced into cells; however, there are some technical issues with the fabrication process and material in terms of cytotoxicity and cost. In this study, polypyrrole (PPy), a biocompatible and conductive polymer, is nano- and micro-structured for an electrode of electroporation by electrochemical polymerization. Nano- and micro-scale dots of PPy are generated by a specific pulse waveform of applied voltage in a considerably low concentration of pyrrole (monomer) solution. The conductivity of PPy is changed from 4 to 16 S/cm by dopant concentration with a range of 0.025 M to 0.2 M. It is demonstrated that electroporation using the PPy and ITO electrodes introduce test agent of molecules (Propidium Iodide) into HeLa cells, where 10 and 50 V of pulse voltage is applied. The electroporation using nano-scale dots of PPy electrodes provides a 40% higher introduction rate than that of the micro-dots of PPy electrodes. The introduction rate in electroporation using the nano-scale dots of PPy can be maintained above 95% regardless of the application time of voltage, whereas that of the micro-scale dots of PPy electrodes increases with the application time. It is reasonable to assume that the nano- and micro-structured PPy electrodes are effective in electroporation, as the introduction rates on these PPy electrodes are higher than that of the ITO electrode. However, the cell viability in the electroporation using the nano-scale of PPy electrodes decreases by approximately 30% with application time. Both the introduction rate and cell viability slightly decrease with the conductivity of the PPy electrode; therefore, they are dominated by surface morphologies of the PPy electrode and applied voltage as compared to that of electrode conductivity. Nevertheless, it is demonstrated that the nano- and micro-structured PPy electrodes improve the efficiency of electroporation owing to the locally concentrated electric field.
{"title":"Fabrication of Nano- and Micro-Structured PPy Electrode and its Application to Electroporation to Cell","authors":"Saki Amaki, Yohei Kato, Tomomi Sudo, Takahiro Kono, Arata Kaneko","doi":"10.20965/ijat.2023.p0603","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0603","url":null,"abstract":"Electroporation using microstructured electrodes, which generate a localized high electric field, allows molecules (genes) to be introduced into cells; however, there are some technical issues with the fabrication process and material in terms of cytotoxicity and cost. In this study, polypyrrole (PPy), a biocompatible and conductive polymer, is nano- and micro-structured for an electrode of electroporation by electrochemical polymerization. Nano- and micro-scale dots of PPy are generated by a specific pulse waveform of applied voltage in a considerably low concentration of pyrrole (monomer) solution. The conductivity of PPy is changed from 4 to 16 S/cm by dopant concentration with a range of 0.025 M to 0.2 M. It is demonstrated that electroporation using the PPy and ITO electrodes introduce test agent of molecules (Propidium Iodide) into HeLa cells, where 10 and 50 V of pulse voltage is applied. The electroporation using nano-scale dots of PPy electrodes provides a 40% higher introduction rate than that of the micro-dots of PPy electrodes. The introduction rate in electroporation using the nano-scale dots of PPy can be maintained above 95% regardless of the application time of voltage, whereas that of the micro-scale dots of PPy electrodes increases with the application time. It is reasonable to assume that the nano- and micro-structured PPy electrodes are effective in electroporation, as the introduction rates on these PPy electrodes are higher than that of the ITO electrode. However, the cell viability in the electroporation using the nano-scale of PPy electrodes decreases by approximately 30% with application time. Both the introduction rate and cell viability slightly decrease with the conductivity of the PPy electrode; therefore, they are dominated by surface morphologies of the PPy electrode and applied voltage as compared to that of electrode conductivity. Nevertheless, it is demonstrated that the nano- and micro-structured PPy electrodes improve the efficiency of electroporation owing to the locally concentrated electric field.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"30 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-05DOI: 10.20965/ijat.2023.p0547
The 14th Best Paper Award 2023 ceremony was held at the University College Dublin, Belfield, Dublin, Ireland, August 23, 2023 in the 72nd CIRP General Assembly, attended by the winner and IJAT committee members who took part in the selection process. At the same time, the 4th Best Review Award 2023 has been decided by IJAT Editorial Committee. The Best Paper was severely selected from among 87 papers published in Vol.16 (2022) and Best Review was selected from 10 reviews published from Vol.12 No.5 (2018) to Vol.16 No.4 (2022). The Best Paper Award winner was given a certificate with a JPY100,000 honorarium, and the Best Review Award winner was given a certificate with award plaque. We extend our warmest congratulations to the winners and express our heartfelt wishes for their continued success in the future.
{"title":"The Best Paper Award 2023 and The Best Review Award 2023 Congratulations!","authors":"","doi":"10.20965/ijat.2023.p0547","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0547","url":null,"abstract":"The 14th Best Paper Award 2023 ceremony was held at the University College Dublin, Belfield, Dublin, Ireland, August 23, 2023 in the 72nd CIRP General Assembly, attended by the winner and IJAT committee members who took part in the selection process. At the same time, the 4th Best Review Award 2023 has been decided by IJAT Editorial Committee. The Best Paper was severely selected from among 87 papers published in Vol.16 (2022) and Best Review was selected from 10 reviews published from Vol.12 No.5 (2018) to Vol.16 No.4 (2022). The Best Paper Award winner was given a certificate with a JPY100,000 honorarium, and the Best Review Award winner was given a certificate with award plaque. We extend our warmest congratulations to the winners and express our heartfelt wishes for their continued success in the future.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"30 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-05DOI: 10.20965/ijat.2023.p0610
Tomoko Aoki, Erika Yamamoto, Hiroshi Masuda
Deterioration surveys of large structures such as furnaces have been mainly conducted by visual inspection, but it is desirable to automatically detect deterioration using point clouds captured by the terrestrial laser scanner. In this study, we propose flexible methods for detecting various scales of cracks, delamination, and adhesion on furnace walls by using a machine learning technique. Since small cracks have few geometrical features, they are detected from the reflection intensity images generated by projecting a point cloud onto a two-dimensional plane. For detecting cracks on the image, we use the U-Net fine-tuned by crack images denoised with a median filter. For detecting delamination and adhesion, a wall surface is approximated by a smooth B-spline surface, and deterioration is detected as differences between the point cloud and the approximated surface. However, in this method, the resolution of the B-spline surface has to be carefully determined according to the expected deterioration sizes. To robustly detect deterioration at various scales, we introduce multiscale 3D features, and detect deterioration using both multiscale 3D features and 2D features. In actual walls, it is difficult to distinguish between cracks and delamination because delamination grows from cracks. To detect both types of deterioration in a uniform manner, we combine the two detectors and propose an integrated detector for detecting deterioration at various scales. Our experimental results showed that our methods could stably detect various scales of degradation on furnace walls.
{"title":"Detection of Multiscale Deterioration from Point-Clouds of Furnace Walls","authors":"Tomoko Aoki, Erika Yamamoto, Hiroshi Masuda","doi":"10.20965/ijat.2023.p0610","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0610","url":null,"abstract":"Deterioration surveys of large structures such as furnaces have been mainly conducted by visual inspection, but it is desirable to automatically detect deterioration using point clouds captured by the terrestrial laser scanner. In this study, we propose flexible methods for detecting various scales of cracks, delamination, and adhesion on furnace walls by using a machine learning technique. Since small cracks have few geometrical features, they are detected from the reflection intensity images generated by projecting a point cloud onto a two-dimensional plane. For detecting cracks on the image, we use the U-Net fine-tuned by crack images denoised with a median filter. For detecting delamination and adhesion, a wall surface is approximated by a smooth B-spline surface, and deterioration is detected as differences between the point cloud and the approximated surface. However, in this method, the resolution of the B-spline surface has to be carefully determined according to the expected deterioration sizes. To robustly detect deterioration at various scales, we introduce multiscale 3D features, and detect deterioration using both multiscale 3D features and 2D features. In actual walls, it is difficult to distinguish between cracks and delamination because delamination grows from cracks. To detect both types of deterioration in a uniform manner, we combine the two detectors and propose an integrated detector for detecting deterioration at various scales. Our experimental results showed that our methods could stably detect various scales of degradation on furnace walls.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"30 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-05DOI: 10.20965/ijat.2023.p0494
Shingo Tajima, Satoshi Iwamoto, Hayato Yoshioka
Vertically articulated industrial robots are suitable for machining purposes owing to their advantages over multi-axis machine tools, such as larger workspace, easier installation, and lower cost. However, the rigidity and positioning accuracy of industrial robots are inferior to those of machine tools, which renders it difficult to maintain the robot posture required for machining operations. This study focuses on improving the accuracy of robot machining based on posture optimization by exploiting the kinematic redundancy of a six-axis vertically articulated robot. To decrease positioning errors caused by static and dynamic external forces during machining, this study proposes a path generation method for a redundant joint that simultaneously considers the static and dynamic rigidity of the machining robot. The relationships between the static and dynamic mechanical characteristics of the machining robot and the redundant angle are illustrated using two maps: a static stiffness map and a natural frequency map. Using these two maps in the proposed path generation method, the redundant angle that can be selected for the robot posture with arbitrary mechanical characteristics is selected. Experimental results confirm that the proposed path generation method can control the priority of reducing static positioning error and vibration amplitude by changing the weight coefficients. In addition, the proposed method can improve positioning accuracy compared with conventional trajectory generation methods for redundant robots.
{"title":"Posture Optimization in Robot Machining with Kinematic Redundancy for High-Precision Positioning","authors":"Shingo Tajima, Satoshi Iwamoto, Hayato Yoshioka","doi":"10.20965/ijat.2023.p0494","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0494","url":null,"abstract":"Vertically articulated industrial robots are suitable for machining purposes owing to their advantages over multi-axis machine tools, such as larger workspace, easier installation, and lower cost. However, the rigidity and positioning accuracy of industrial robots are inferior to those of machine tools, which renders it difficult to maintain the robot posture required for machining operations. This study focuses on improving the accuracy of robot machining based on posture optimization by exploiting the kinematic redundancy of a six-axis vertically articulated robot. To decrease positioning errors caused by static and dynamic external forces during machining, this study proposes a path generation method for a redundant joint that simultaneously considers the static and dynamic rigidity of the machining robot. The relationships between the static and dynamic mechanical characteristics of the machining robot and the redundant angle are illustrated using two maps: a static stiffness map and a natural frequency map. Using these two maps in the proposed path generation method, the redundant angle that can be selected for the robot posture with arbitrary mechanical characteristics is selected. Experimental results confirm that the proposed path generation method can control the priority of reducing static positioning error and vibration amplitude by changing the weight coefficients. In addition, the proposed method can improve positioning accuracy compared with conventional trajectory generation methods for redundant robots.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135254638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-05DOI: 10.20965/ijat.2023.p0486
Akinori Saito, Yoji Jimba
Machining centers have played a central role in the production field for nearly half a century. Accuracy inspections of machining centers are performed as per ISO standards; however, the accuracy performance of machining centers is often not checked directly after delivery to the factory unless there is a collision between a tool and a workpiece or product failure. Although positioning accuracy is fundamental to the performance of machining centers, the need for expensive laser interferometers and the time required for the setup present barriers to owning and inspecting them. This study proposes a simple method for measuring positioning accuracy that does not require a time-consuming setup of the measurement device or expensive devices. Therefore, the user of the machine tool can own and use the proposed method for daily inspection to identify changes in the positioning accuracy of the numerically controlled machine tool more quickly.
{"title":"Simple Measuring of Positioning Accuracy for Machining Centers Using Image Matching","authors":"Akinori Saito, Yoji Jimba","doi":"10.20965/ijat.2023.p0486","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0486","url":null,"abstract":"Machining centers have played a central role in the production field for nearly half a century. Accuracy inspections of machining centers are performed as per ISO standards; however, the accuracy performance of machining centers is often not checked directly after delivery to the factory unless there is a collision between a tool and a workpiece or product failure. Although positioning accuracy is fundamental to the performance of machining centers, the need for expensive laser interferometers and the time required for the setup present barriers to owning and inspecting them. This study proposes a simple method for measuring positioning accuracy that does not require a time-consuming setup of the measurement device or expensive devices. Therefore, the user of the machine tool can own and use the proposed method for daily inspection to identify changes in the positioning accuracy of the numerically controlled machine tool more quickly.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135254635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-05DOI: 10.20965/ijat.2023.p0433
Hayato Yoshioka
The social demands for manufacturing systems are constantly changing with the times. In recent years, environmental and social issues have been complicating these demands. For example, all industrial sectors need to consider environmentally responsible ways to achieve sustainable development goals in a time of paradigm shifts. The demands in the manufacturing field include high productivity, high quality, low energy consumption, and help for aging operators. To meet these various demands for manufacturing systems, we must create innovative manufacturing technologies to realize advanced production systems. This special issue focuses on state-of-the-art machine tools and manufacturing technologies to accelerate production engineering innovation. This issue consists of eleven research papers covering the following fields. - Advanced structure and drive systems in machine tools - Industrial robot applications - Advanced cutting technologies - Evaluation and calibration technologies of motion error - Surface finishing technologies - Grinding of hard and brittle materials All of these research contributions were presented at IMEC2022, a joint event with JIMTOF2022, held in Tokyo, Japan in 2022. I would like to sincerely thank all the authors for their contributions, and I sincerely hope that the papers in this special issue further contribute to the development of our future society.
{"title":"Special Issue on the Latest Machine Tool and Manufacturing Technologies","authors":"Hayato Yoshioka","doi":"10.20965/ijat.2023.p0433","DOIUrl":"https://doi.org/10.20965/ijat.2023.p0433","url":null,"abstract":"The social demands for manufacturing systems are constantly changing with the times. In recent years, environmental and social issues have been complicating these demands. For example, all industrial sectors need to consider environmentally responsible ways to achieve sustainable development goals in a time of paradigm shifts. The demands in the manufacturing field include high productivity, high quality, low energy consumption, and help for aging operators. To meet these various demands for manufacturing systems, we must create innovative manufacturing technologies to realize advanced production systems. This special issue focuses on state-of-the-art machine tools and manufacturing technologies to accelerate production engineering innovation. This issue consists of eleven research papers covering the following fields. - Advanced structure and drive systems in machine tools - Industrial robot applications - Advanced cutting technologies - Evaluation and calibration technologies of motion error - Surface finishing technologies - Grinding of hard and brittle materials All of these research contributions were presented at IMEC2022, a joint event with JIMTOF2022, held in Tokyo, Japan in 2022. I would like to sincerely thank all the authors for their contributions, and I sincerely hope that the papers in this special issue further contribute to the development of our future society.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135254642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}