Robotics and Computer-integrated Manufacturing最新文献

{"title":"A hybrid model in a nonlinear disturbance observer for improving compliance error compensation of robotic machining","authors":"Ali Khishtan ,&nbsp;Seong Hyeon Kim ,&nbsp;Jihyun Lee","doi":"10.1016/j.rcim.2024.102887","DOIUrl":"10.1016/j.rcim.2024.102887","url":null,"abstract":"<div><div>The joint deflection of robots in machining degrades product accuracy. Compliance error compensation has been investigated to reduce the static deflection of robotic machining. The challenge in compliance error compensation is accurately measuring the deflection or cutting force. External sensors have been used to measure them in robotic machining, but it is not practical. The authors proposed a nonlinear disturbance observer to indirectly measure the cutting force online in robotic machining in the previous study. The observer, however, needs to utilize the robot model that includes characteristics of high nonlinearity, uncertainty, and high dynamic variation for different robot postures. After investigating these challenges of modeling, this paper proposes a hybrid modeling approach combining a physics-based model with a new empirical friction model, and a data-driven model to accurately estimate the cutting force while minimizing the error of the robot's mathematical model. The joint torque calculated from the hybrid model can cover the effect of joints' postures and speeds on the varying dynamic in its workspace. Real-time optimization just before cutting is also proposed to adapt to the real-time joint's motion conditions. The experimental results from aluminum multi-axis cutting show that the estimated cutting force via the nonlinear disturbance observer based on the proposed hybrid modeling approach can improve its accuracy up to 45% and 74% in the <em>x</em> and <em>y</em> directions respectively, compared to the physics-based modeling approach. The deflection of the tool center point can be compensated by using a compliance error compensation method up to 79.1% and 75.4% in the <em>x</em> and <em>y</em> directions, respectively, at 0.5 <em>mm/s</em> feed rate, and up to 77.2% and 78.9% at 3 <em>mm/s</em> feed rate. Consequently, the approaches developed in this paper can solve the problems of conventional robot modeling and improve the accuracy of robot machining.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102887"},"PeriodicalIF":9.1,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tool breakage monitoring driven by the real-time predicted spindle cutting torque using spindle servo signals","authors":"Yinghao Cheng ,&nbsp;Yingguang Li ,&nbsp;Guangxu Li ,&nbsp;Xu Liu ,&nbsp;Jinyu Xia ,&nbsp;Changqing Liu ,&nbsp;Xiaozhong Hao","doi":"10.1016/j.rcim.2024.102888","DOIUrl":"10.1016/j.rcim.2024.102888","url":null,"abstract":"<div><div>Monitoring tool breakage during computer numerical control machining is essential to ensure machining quality and equipment safety. In consideration of the low cost in long-term use and the non-invasiveness to workspace, using servo signals of machine tools to monitor tool breakage has been viewed as the solution that has great potential to be applied in real industry. However, because machine tool servo signals can only partially and indirectly reflect tool conditions, the accuracy and reliability of existing methods still need to be improved. To overcome this challenge, a novel two-step data-driven tool breakage monitoring method using spindle servo signals is proposed. Since spindle cutting torque is acknowledged as one of the most effective and reliable physical signals for detecting tool breakage, it is introduced as the key intermediate variable from spindle servo signals to tool conditions. The monitored spindle servo signals are used to predict the spindle cutting torque in real time based on a long short-term memory neural network, and then the predicted spindle cutting torque is used to detect tool breakage based on a one-dimensional convolutional neural network. The experimental results show that the proposed method can accurately predict the spindle cutting torque for normal tools and broken tools. Compared with the tool breakage monitoring methods that directly use spindle servo signals, the proposed method has higher detection accuracy and more reliable detection results, and the performance is more stable when increasing the detection frequency and decreasing training data.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102888"},"PeriodicalIF":9.1,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Communicating robots’ intent through visual cues enhances human anticipatory behavior in human–dual robot collaboration","authors":"Loizos Psarakis,&nbsp;Dimitris Nathanael,&nbsp;Nicolas Marmaras","doi":"10.1016/j.rcim.2024.102886","DOIUrl":"10.1016/j.rcim.2024.102886","url":null,"abstract":"<div><div>The present study aims at exploring the effect of communicating robots’ intent through visual cues, to the human on a complex human-robot collaborative task. Specifically, it aims to investigate (i) whether the use of such “anticipatory cues” will have a positive effect on task efficiency, human safety and collaborating fluency, (ii) the degree of this effect with varying robots’ speed and (iii) whether a retention effect will be observed after the removal of the cues. For exploring these issues, a human - dual robot industrial assembly task was designed in a Virtual Reality simulation environment and testing was carried out by 64 volunteer participants. Results showed that communicating robots’ intent through visual cues enhanced human anticipatory behavior, resulting in a significant improvement in human safety, team efficiency and collaborative fluency, in conjunction with a favorable subjective tendency towards the robots. However, the positive effect of the anticipatory cues was not found to increase with higher robot speed. Finally, the findings suggest that prior exposure to the cues made participants more confident in coordinating with the robots, even when the cues were removed from them, thus retaining their prior efficiency but with a negative effect on safety. In summary, the study provides evidence that use of anticipatory visual cues accelerates the legibility of robot movement and fosters human confidence and familiarization. The use of anticipatory cues seems promising for high-pace, non-repetitive interactions with collaborative robots or as a training aid in more repetitive human-robot collaborative tasks.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102886"},"PeriodicalIF":9.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A point cloud registration algorithm considering multi-allowance constraints for robotic milling of complex parts","authors":"Jixiang Yang,&nbsp;Jinxian Zhang,&nbsp;Tianshu Song,&nbsp;Han Ding","doi":"10.1016/j.rcim.2024.102885","DOIUrl":"10.1016/j.rcim.2024.102885","url":null,"abstract":"<div><div>Adaptive allocation of the machining allowance is the crucial factor in ensuring the machining accuracy of complex parts. In this work, we present a multi-objective constraint registration method. First, an improved point cloud segmentation method is developed by combining point search and region data expansion algorithms. Afterward, the machining allowance is accurately calculated by using statistical analysis and multi-point sampling strategies to enhance the calculation accuracy of the point-to-triangular patch distance. Finally, a registration objective function is established by considering the allowance constraints of various geometric regions of the workpiece, and the particle swarm optimization algorithm is used to solve the optimum solution. The proposed multi-constraint registration method realizes optimal allocation of the allowance in different regions, which offers a reference coordinate system for the robotic milling of complex free-formed parts. Simulation and experimental results reveal that the developed method satisfies the minimum registration error while ensuring the allocation of allowance in the robotic milling of the casing cavity compared with other methods.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102885"},"PeriodicalIF":9.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sigmoid angle-arc curves: Enhancing robot time-optimal path parameterization for high-order smooth motion","authors":"Shize Zhao,&nbsp;Tianjiao Zheng,&nbsp;Chengzhi Wang,&nbsp;Ziyuan Yang,&nbsp;Tian Xu,&nbsp;Yanhe Zhu,&nbsp;Jie Zhao","doi":"10.1016/j.rcim.2024.102884","DOIUrl":"10.1016/j.rcim.2024.102884","url":null,"abstract":"<div><div>Trajectory planning is crucial in the motion planning of robots, where finding the time-optimal path parameterization (TOPP) of a given path subject to kinodynamic constraints is an important component of trajectory planning. The tangential discontinuity at the intersection of continuous line segments limits the speed of trajectory planning and can easily cause jitter and over-constraint phenomena. Smooth transitions at corners can be achieved by inserting parameter spline curves. However, due to the insensitivity of parameter spline curves to arc length, their performance in the application of the TOPP algorithm, which relies on the higher-order robot kinematics smoothness (i.e., the function <span><math><mrow><mi>q</mi><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow></mrow></math></span> of the configuration space to the Cartesian space), fails to meet expectations.</div><div>A smoothing method suitable for the TOPP algorithm is proposed: Sigmoid Angle-Arc Curve (SAAC). This curve exhibits excellent performance in smooth corner transitions of the TOPP algorithm and is parameterized using arc length. The curvature and geometry of its curves can be expressed analytically in terms of arc lengths. Compared with the traditional B-spline method and the symmetric Euler spiral blending (SE-spiral), SAAC can provide smoother <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> robot kinematics characteristics. Using the TOPP algorithm based on SAAC can significantly enhance the robustness of the TOPP algorithm, significantly reduce jerks, and reduce the time required for movement.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102884"},"PeriodicalIF":9.1,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142326346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A survey on potentials, pathways and challenges of large language models in new-generation intelligent manufacturing","authors":"Chao Zhang ,&nbsp;Qingfeng Xu ,&nbsp;Yongrui Yu ,&nbsp;Guanghui Zhou ,&nbsp;Keyan Zeng ,&nbsp;Fengtian Chang ,&nbsp;Kai Ding","doi":"10.1016/j.rcim.2024.102883","DOIUrl":"10.1016/j.rcim.2024.102883","url":null,"abstract":"<div><div>Nowadays, Industry 5.0 starts to gain attention, which advocates that intelligent manufacturing should adequately consider the roles and needs of humans. In this context, how to enhance human capabilities or even liberate humans from the processes of perception, learning, decision-making, and execution has been one of the key issues to be addressed in intelligent manufacturing. Large language models (LLMs), as the breakthrough in new-generation artificial intelligence, could provide human-like interaction, reasoning, and replies suitable for various application scenarios, thus demonstrating significant potential to address the above issues by providing aid or becoming partners for humans in perception, learning, decision-making, and execution in intelligent manufacturing. The combination of LLMs and intelligent manufacturing has inherent advantages and is expected to become the next research hotspot. Hence, this paper primarily conducts a systematic literature review on the application of LLMs in intelligent manufacturing to identify the promising research topics with high potential for further investigations. Firstly, this paper reveals the concept, connotation, and foundational architecture of LLMs. Then, several typical and trending interdisciplinary LLM applications, such as healthcare, drug discovery, social &amp; economic, education, and software development, are summarized, on which an LLM-enabled intelligent manufacturing architecture is designed to provide a reference for applying LLMs in intelligent manufacturing. Thirdly, the specific pathways for applying LLMs in intelligent manufacturing are explored from the perspectives of design, production, and service. Finally, this paper identifies the limitations, barriers, and challenges that will be encountered during the research and application of LLMs in intelligent manufacturing, while providing potential research directions to address these limitations, barriers, and challenges.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102883"},"PeriodicalIF":9.1,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A robotized framework for real-time detection and in-situ repair of manufacturing defects in CFRP patch placement","authors":"Yi Gong ,&nbsp;Xiangli Li ,&nbsp;Rui Zhou ,&nbsp;Miao Li ,&nbsp;Sheng Liu","doi":"10.1016/j.rcim.2024.102882","DOIUrl":"10.1016/j.rcim.2024.102882","url":null,"abstract":"<div><div>Carbon fiber reinforced polymers (CFRP) have significant applications in aerospace and automotive manufacturing. However, due to the complexity of CFRP structures, manufacturing defects are challenging to avoid and even affect the mechanical properties. Timely detection and repair are essential to ensure product quality. In this study, we propose a robotized framework for real-time detection and in-situ repair of manufacturing defects in CFRP patch placement. First, the influence of three typical defects (delamination, wrinkle and impurity) on mechanical properties is analyzed through numerical analysis. Then, a defect detection model is improved using the channel attention mechanism and decoupling head module, which enhances detection accuracy and the ability to identify small and deep defects. Based on the identification result, a corresponding repair strategy is generated, which considers the effects of force, path, heating and repair modes. The experimental results demonstrate that the tensile stiffness and bending strength of the repaired material are improved by 12.34% and 230.92%, respectively.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102882"},"PeriodicalIF":9.1,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Finite-time SMC-based admittance controller design of macro-micro robotic system for complex surface polishing operations","authors":"Yaohua Zhou ,&nbsp;Chin-Yin Chen ,&nbsp;Guilin Yang ,&nbsp;Chi Zhang","doi":"10.1016/j.rcim.2024.102881","DOIUrl":"10.1016/j.rcim.2024.102881","url":null,"abstract":"<div><div>In the field of robotic polishing, achieving uniform material removal typically involves addressing the issue of constant contact force control. However, multi-source external disturbances in the polishing scenarios of complex workpiece surfaces can severely affect the robot’s force control accuracy. To enhance the responsiveness and disturbance rejection capabilities of robots in the compliant polishing process, this paper proposes an adaptive admittance controller with practical finite-time stability. A virtual control input is introduced into the basic admittance control framework in light of the state space theory, aiming to provide flexibility for common adaptive law designs. On this basis, a robust sliding mode control (SMC) algorithm is proposed to suppress external disturbances. The force tracking error is theoretically proven to achieve finite-time convergence when applying the proposed control strategy. Experimental results across various polishing scenarios demonstrate that, compared with the existing admittance control strategies, the proposed method can reduce fluctuations of the polishing force and improve the surface quality, thus verifying its effectiveness.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102881"},"PeriodicalIF":9.1,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the consistency of path smoothing and trajectory planning in CNC machining: A surface-centric evaluation","authors":"Yunan Wang,&nbsp;Chuxiong Hu,&nbsp;Zeyang Li,&nbsp;Zhirui He,&nbsp;Shiwen Lin,&nbsp;Yushuo Wang,&nbsp;Shize Lin,&nbsp;Jichuan Yu,&nbsp;Zhao Jin,&nbsp;Yu Zhu","doi":"10.1016/j.rcim.2024.102873","DOIUrl":"10.1016/j.rcim.2024.102873","url":null,"abstract":"<div><div>Path smoothing and trajectory planning are universally applied in computer-numerical-control (CNC) machining to avoid natural discontinuity of tangency and curvature at the junctions of G01 blocks. However, most existing methods primarily focus on path-centric indicators that consider the toolpath as a continuous curve, such as contour error and manufacturing efficiency, neglecting the global machining quality and failing to avoid surface inconsistencies, such as single tool marks. This paper establishes a theoretical framework to evaluate the global continuity of toolpaths and trajectories, proposing the consistency as a surface-centric evaluation that considers toolpaths as a surface in CNC machining. In this paper, the consistency is defined as similarity between adjacent toolpaths and trajectories when facing similar input fold-paths in single-point milling. The consistency of four typical existing methods representing a broad category of typical approaches is investigated based on the developed theory. As a theoretically ideal objective, the proposed strong consistency requires a path smoothing method robust to any positional disturbance on the input fold-paths, and this paper points out that few algorithms have achieved strong consistency so far. The proposed weak consistency focusing on the tangential disturbance is practical in the industry. Filtering-based methods without contour error limitations are proved to achieve weak consistency, and smoothing methods with explicit geometric constraints fail to achieve weak consistency. To facilitate evaluation on the consistency of more complex methods, this paper proposes numerical benchmarks and quantitative indicators which can determine whether a method is consistent by numerical experiments. Conducted on a 3-axis machine tool with a ball-end milling cutter, real-world experiments show that inconsistencies in toolpaths’ position and trajectories’ feedrate causes surface inconsistencies like single tool marks. The proposed consistency theory and the carefully designed benchmarks can serve as a novel evaluation for path smoothing and trajectory planning from a global perspective, and it can help to identify areas where inconsistencies may occur in single-point milling.</div></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102873"},"PeriodicalIF":9.1,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a mixed robotic machining system and its application in support removal from metal additive manufactured thin-wall parts","authors":"Pengfei Su ,&nbsp;Wei Wang ,&nbsp;Kaiyuan Liu ,&nbsp;Jin Zhang ,&nbsp;Yantao He ,&nbsp;Zhimin Wang ,&nbsp;Lianyu Zheng","doi":"10.1016/j.rcim.2024.102878","DOIUrl":"10.1016/j.rcim.2024.102878","url":null,"abstract":"<div><p>Robotic machining could provide a solution for removing supports from metal additive manufactured workpieces, replacing labor-intensive work. However, the robot’s intrinsic weaknesses of low positioning accuracy and structural rigidity primarily restrict its applications. Improving the accuracy of robotic machining remains an unresolved issue. A mixed solution is proposed, in which a portable CNC machine with the capability of visual feature recognition is equipped with a universal industrial robot. The robot implements positioning motions in a large space, while the portable CNC fulfills accurate machining motions on a local feature of the workpiece. A sizeable weight of the portable CNC exerts a moderate load on the industrial robot’s joints, increasing joint stiffness. The mixed machining system exhibits high accuracy and stiffness when milling a steel/titanium alloy workpiece, achieving tolerances up to ±0.04 mm on a 60×80 mm U-shaped path without exciting any structural vibration modes. When the dimension of the workpiece exceeds the machining range of the portable CNC, a combined algorithm of coarse-fine registration based visual identification and robot error compensation is designed to align the spatial coordinates of the machining motion with that of the positioning motion, thereby extending the machining range with high accuracy. Through the proposed mixed robot machining method, experiments of doubling the machining range have been done to verify that the mixed machining robotic system is able to slot a 550 mm-long path with accuracy of ±0.1 mm. Furthermore, the mixed robotic machining system is applied to recognize and remove multiple supports of lattices, grids and ribs from a titanium-alloy additive manufactured thin-wall workpiece with high accuracy and high efficiency.</p></div>","PeriodicalId":21452,"journal":{"name":"Robotics and Computer-integrated Manufacturing","volume":"92 ","pages":"Article 102878"},"PeriodicalIF":9.1,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142274888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}