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A Vision-based Human Digital Twin Modelling Approach for Adaptive Human-Robot Collaboration 一种基于视觉的人机自适应协作数字孪生建模方法
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-27 DOI: 10.1115/1.4062430
Junming Fan, Pai Zheng, Carman K. M. Lee
Human-robot collaboration (HRC) has been regarded as one of the most promising paradigms for human-centric smart manufacturing in the context of Industry 5.0. To improve human well-being and robotic flexibility in HRC, a plethora of works around human body perception have emerged over the years, but most of them only considered a specific facade of human recognition while lacking a holistic perspective of the human operator. To this end, this study proposes an exemplary vision-based Human Digital Twin (HDT) model for highly dynamic HRC applications. The model mainly consists of a convolutional neural network that can simultaneously model the hierarchical human status including 3D human posture, action intention, and ergonomic risk. Then, on the basis of the constructed HDT, a robotic motion planning strategy is further introduced with the aim of adaptively optimizing the robotic motion trajectory. Further experiments and case studies are conducted in an HRC scenario to demonstrate the effectiveness of our approach.
人机协作(HRC)被认为是工业5.0背景下以人为中心的智能制造最有前途的范例之一。为了提高HRC中的人类福祉和机器人灵活性,多年来出现了大量围绕人体感知的工作,但其中大多数只考虑了人类识别的特定外观,而缺乏人类操作员的整体视角。为此,本研究提出了一个典型的基于视觉的人类数字孪生(HDT)模型,用于高度动态的HRC应用。该模型主要由卷积神经网络组成,该网络可以同时对三维人体姿态、动作意图和人体工程学风险等分层人体状态进行建模。然后,在构建的HDT基础上,进一步引入机器人运动规划策略,以自适应优化机器人运动轨迹。在HRC场景中进行了进一步的实验和案例研究,以证明我们的方法的有效性。
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引用次数: 1
Bubble Effects on Manufacturing of Silicon Nanowires by Metal-Assisted Chemical Etching 金属辅助化学刻蚀制备硅纳米线的气泡效应
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-21 DOI: 10.1115/1.4062392
Pee-Yew Lee, C. Weng, H. Huang, Li-Yan Wu, Guo-Hao Lu, Chao-Feng Liu, Cheng-You Chen, Ting-Yu Li, Yung-Sheng Lin
Micro/nano-textured Si wafers manufactured using metal-assisted chemical etching (MACE) have been the focus of several studies, but the mechanism of bubble generation during the MACE process affecting textured surfaces has rarely been reported. This study investigated the bubble effect due to the different placement patterns of the Si wafer (face-up, stirred face-down, and face-down). The results indicated that the placement pattern of the Si wafer notably influences the uniformity of outward appearance. However, no significant differences were noted in the scanning electron microscopy images of Si nanowires (SiNWs) at 0.5 h of etching. At 2 h of etching, the outward appearance uniformity of face-up etching was more homogeneous than that of stirred face-down and face-down patterns, and the SiNWs processed through face-up etching were longer (41 μm) than those subjected to stirred face-down etching (36 μm) and face-down etching (32 μm). Therefore, the placement pattern of Si wafer can affect the uniformity and properties of SiNWs because of bubbles trapped inside cavities or between SiNWs.
使用金属辅助化学蚀刻(MACE)制造的微/纳米织构Si晶片一直是一些研究的焦点,但很少报道MACE过程中气泡产生对织构表面的影响机制。本研究调查了硅晶片不同放置模式(面朝上、搅拌面朝下和面朝下)引起的气泡效应。结果表明,硅片的放置方式对其外观的均匀性有显著影响。然而,在蚀刻0.5小时时,在Si纳米线(SiNWs)的扫描电子显微镜图像中没有观察到显著差异。在蚀刻2小时时,面朝上蚀刻的外观均匀性比搅拌面朝下和面朝下图案更均匀,并且通过面朝上蚀刻处理的SiNW比经过搅拌面朝下蚀刻(36μm)和面朝下蚀刻的SiNW长(41μm)。因此,硅晶片的放置图案会影响SiNWs的均匀性和性能,因为气泡被困在空腔内或SiNWs之间。
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引用次数: 0
A study on converging-diverging nozzle design for supersonic spraying of liquid droplets toward nanocoating applications 用于纳米涂层应用的液滴超声喷涂的会聚-发散喷嘴设计研究
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-19 DOI: 10.1115/1.4062351
Semih Akin, Puyuan Wu, Chandra Nath, Jun Chen, M. Jun
Supersonic cold spraying of liquid droplets containing functional nanomaterials is of particular interest in advanced thin-film coating, that enabling high-adhesion strength particle deposition. In cold spraying, the optimum design of the supersonic nozzle is essential for accelerating particles to desired velocities. However, research on the supersonic nozzle design for liquid droplets is limited. Thus, we thoroughly investigate the influence of nozzle geometrical parameters (i.e., throat diameter, exit diameter, divergent length) on droplets acceleration by numerical modeling followed by experimental validation, and a case study on surface coating application. Two-phase flow modeling was used to predict droplets' behavior in continuous gas flow for different nozzle configurations. The results show that the nozzle expansion ratio - a function of throat and exit diameters - has a significant influence on droplet velocity, followed by divergent length. In particular, to correctly accelerate “low-inertia liquid droplets”, optimum nozzle expansion ratio for an axisymmetric convergent-divergent nozzle is found to be in a range of 1.5-2.5 for different sets of parameters, which is different than the recommended expansion ratio (i.e., 5-9) for cold spraying of conventional “metal” particles. Based on the simulation results, an optimal design of supersonic nozzle is selected and prototyped for the experimental studies. Numerical modeling results are validated by particle image velocimetry (PIV) measurements. Moreover, coating experiments confirm the adaptability of the optimized nozzle for supersonic cold spraying of droplets containing nanoparticles, which thereby has the potential for rapid production of advanced thin films.
含有功能性纳米材料的液滴的超音速冷喷涂在先进的薄膜涂层中尤其令人感兴趣,这种涂层能够实现高粘附强度的颗粒沉积。在冷喷涂中,超音速喷嘴的优化设计对于将颗粒加速到所需速度至关重要。然而,对液滴超音速喷嘴设计的研究是有限的。因此,我们通过数值建模、实验验证和表面涂层应用的案例研究,深入研究了喷嘴几何参数(即喉部直径、出口直径、发散长度)对液滴加速的影响。两相流模型用于预测不同喷嘴配置下连续气流中液滴的行为。结果表明,喷嘴膨胀比(喉部和出口直径的函数)对液滴速度有显著影响,其次是发散长度。特别是,为了正确加速“低惯性液滴”,对于不同的参数组,轴对称收敛-发散喷嘴的最佳喷嘴膨胀比在1.5-2.5的范围内,这与传统“金属”颗粒冷喷涂的推荐膨胀比(即5-9)不同。基于仿真结果,选择了超声速喷嘴的优化设计方案,并对其进行了实验研究。数值模拟结果通过粒子图像测速仪(PIV)测量得到验证。此外,涂层实验证实了优化喷嘴对含有纳米颗粒的液滴的超音速冷喷涂的适应性,从而具有快速生产先进薄膜的潜力。
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引用次数: 0
Algebraic modeling of cylindrical interference-free power-skiving tool for involute internal gear cutting with tilt angle 圆柱无干涉电动刮削渐开线内齿轮的代数建模
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-12 DOI: 10.1115/1.4062312
The development of feasible methods for the design of power-skiving tools without cutting interference is essential in ensuring the accuracy of involute internal machined gears. One of the most crucial points in obtaining interference-free and re-sharpenable power-skiving tools is that of determining the cutting edge and clearance surface. The present study introduces a tilt angle during the power-skiving process to design a simple cylindrical interference-free tool shape, in which the shape of the cutting edge remains unchanged after re-sharpening. The relative position between the new tool center point and gear during machining is similarly unchanged after the re-sharpening process. In addition, the clearance angle between the tool and the gear can be easily adjusted simply by changing the tilt angle of the tool during power-skiving. The validity of the proposed design method is demonstrated through a simple numerical example. The simulation results confirm the feasibility of the proposed method.
开发可行的无切削干涉电动刮削工具设计方法对于确保渐开线内啮合齿轮的精度至关重要。在获得无干涉和可再磨的电动刮削工具时,最关键的一点是确定切削刃和间隙表面。本研究引入了动力刮削过程中的倾斜角度,以设计一种简单的圆柱形无干涉刀具形状,其中切削刃的形状在重新磨锐后保持不变。在加工过程中,新刀具中心点和齿轮之间的相对位置在再磨锐过程之后类似地保持不变。此外,在动力刮削过程中,只需改变刀具的倾斜角度,就可以很容易地调整刀具和齿轮之间的间隙角。通过一个简单的算例验证了该设计方法的有效性。仿真结果验证了该方法的可行性。
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引用次数: 0
Surface Characterization of Three-Dimensional Printed Fiber-Reinforced Polymer Following an In-Process Mechanical–Chemical Finishing Method 三维打印纤维增强聚合物在加工过程中机械化学整理方法后的表面表征
3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-11 DOI: 10.1115/1.4062146
Aman Nigam, Bruce L. Tai
Abstract Fiber-reinforced polymer (FRP) additive manufacturing has transformed fused filament fabrication (FFF) by manufacturing products with excellent mechanical characteristics. However, the surface finish and dimensional characteristics of printed FRP parts are typically poor due to protruding fibers and the stair-stepping effect. This parametric study examined an in-process combined mechanical plus chemical finishing technique to improve the surface finish of FRPs manufactured through FFF. This process is particularly useful for internal or complex features that cannot be otherwise finished after printing. In this work, a custom-built three-axis machine with printing, machining, and chemical finishing capabilities was used for the experiments. The effect of mechanical finishing on surface characteristics was first quantified using chip load and spindle speed as independent parameters. Following that, chemical treatment was performed on the already machined surface at two pressing depths (PD), which control the normal contact force acting on the surface. The best surface characteristics were observed at a low chip load of 0.007 mm and a moderately high spindle speed of 20,000 rpm. After chemical treatment using a lower PD, a surface roughness reduction was observed (from 8.041 to 4.988 µm). Increased PD led to even lower Ra values (from 4.988 to 3.538 µm) due to the enhanced fiber encapsulation phenomenon. Finally, the dimensional analysis revealed that the final combined finished samples had less than 1%-dimensional error (0.05 mm), which is an order of magnitude less than the typical error in FFF-printed parts (0.5 mm). This study provides means to conduct finishing in an additive manufacturing environment to reduce the time, labor, and cost associated with post-processing.
摘要纤维增强聚合物(FRP)增材制造通过制造具有优异力学特性的产品,改变了熔融长丝制造(FFF)。然而,由于纤维突出和台阶效应,打印FRP部件的表面光洁度和尺寸特性通常较差。本参数研究考察了一种过程中机械加化学综合整理技术,以提高通过FFF制造的frp的表面光洁度。这个过程对内部或复杂的特征特别有用,否则不能在打印后完成。在这项工作中,使用了一台定制的三轴机器,具有印刷,加工和化学整理功能。首先以切屑负荷和主轴转速为独立参数,量化了机械精加工对表面特性的影响。然后,在两个压制深度(PD)下对已经加工的表面进行化学处理,PD控制作用在表面上的法向接触力。在0.007 mm的低切屑负载和20,000 rpm的中高主轴转速下,观察到最佳的表面特性。使用较低PD进行化学处理后,观察到表面粗糙度降低(从8.041µm降至4.988µm)。由于增强的光纤封装现象,PD增加导致Ra值更低(从4.988降至3.538µm)。最后,尺寸分析表明,最终组合成品样品的尺寸误差小于1% (0.05 mm),这比fff打印部件的典型误差(0.5 mm)小一个数量级。本研究提供了在增材制造环境中进行精加工的方法,以减少与后处理相关的时间、劳动力和成本。
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引用次数: 0
Numerical investigation into the influence of alloy type and thermo-mechanics on void formation in Friction Stir Welding of Aluminium alloys 铝合金搅拌摩擦焊中合金类型和热力学对气孔形成影响的数值研究
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-05 DOI: 10.1115/1.4062270
M. Ansari, Hemant Agiwal, D. Franke, M. Zinn, F. Pfefferkorn, S. Rudraraju
This study employs a high-fidelity numerical framework to determine the plastic material flow patterns and temperature distributions that lead to void formation during friction stir welding (FSW), and to relate the void morphologies to the underlying alloy material properties and process conditions. Three aluminum alloys, viz., 6061-T6, 7075-T6, and 5053-H18 were investigated under varying traverse speeds. The choice of aluminum alloys enables investigation of a wide range of thermal and mechanical properties. The numerical simulations were validated using experimental observations of void morphologies in these three alloys. Temperatures, plastic strain rates, and material flow patterns are considered. The key results from this study are: (1) The predicted stir zone and void morphology are in good agreement with the experimental observations, (2) The temperature and plastic strain-rate maps in the steady-state process conditions show a strong dependency on the alloy type and traverse speeds, (3) The material velocity contours provide a good insight into the material flow in the stir zone for the FSW process conditions that result in voids as well as those that do not result in voids. The numerical model and the ensuing parametric studies presented in this work provide a framework for understanding material flow under different process conditions in aluminum alloys, and potentially in other alloys. Furthermore, the utility of the numerical model for making quantitative predictions and investigating different process parameters to reduce void formation is demonstrated.
本研究采用高保真数值框架来确定搅拌摩擦焊(FSW)过程中导致空洞形成的塑性材料流动模式和温度分布,并将空洞形态与潜在的合金材料性能和工艺条件联系起来。研究了6061-T6、7075-T6和5053-H18三种铝合金在不同导线速度下的性能。铝合金的选择可以研究广泛的热性能和机械性能。通过对三种合金空穴形貌的实验观察,验证了数值模拟的正确性。考虑了温度、塑性应变率和材料流动模式。关键从这项研究结果:(1)预测搅拌区和孔隙形态良好的协议与实验观察,(2)稳态过程中的温度和塑性应变率图条件下表现出强烈的依赖合金类型和遍历速度,(3)材料的速度轮廓提供良好的洞察物质流在搅拌区对FSW过程条件,导致孔隙以及那些不会导致空洞。本研究中提出的数值模型和随后的参数研究为理解铝合金和其他合金在不同工艺条件下的物质流动提供了一个框架。此外,还证明了数值模型在定量预测和研究不同工艺参数以减少孔隙形成方面的效用。
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引用次数: 0
Multi-physics investigations on the gas-powder flow and the molten pool dynamics during directed energy deposition process 定向能沉积过程中气粉流动和熔池动力学的多物理场研究
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-04-03 DOI: 10.1115/1.4062259
Chenghong Duan, X. Cao, Xiangpeng Luo, Dazhi Shang, X. Hao
In order to establish a high-fidelity mechanism model for investigating the molten pool behaviors during directed energy deposition (DED) process, a molten pool dynamics model combined with the discrete element method is developed in present study. The proposed model contains newly added particle sources to further intuitively reproduce the interaction between the discrete powder particles and the molten pool. Meanwhile, the effects of the nozzle structure, carrier gas and shielding gas on the feedstock feeding process are simulated in detail using the gas-powder flow model based on the multi-phase flow theory. The gas-powder flow model is used to provide the reasonable outlet velocities, focal distance and radius of the focal point for the particle sources in the molten pool dynamics model, which solves the difficulty that the motion state of the powder streams obtained by the molten pool dynamics simulation are hard to reproduce the actual situation. Besides, relevant experiments are conducted to verify the accuracy of the developed models. The predicted parameters of the powder streams are consistent with the experiment, and the deviations of the predicted molten pool dimensions are less than 10%. The heat and mass transfer phenomena inside the molten pool are also revealed. Furthermore, the maximum size of the spherical pore defects is predicted to be 18.6 µm, which is underestimated by 7% compared to the microscopic observation. Taken together, the developed numerical model could augment and improve the training samples for the machine learning modelling of DED process.
为了建立一个高保真度的机制模型来研究定向能沉积(DED)过程中的熔池行为,本研究开发了一个结合离散元方法的熔池动力学模型。所提出的模型包含新添加的颗粒源,以进一步直观地再现离散粉末颗粒与熔池之间的相互作用。同时,利用基于多相流理论的气粉流动模型,详细模拟了喷嘴结构、载气和保护气对进料过程的影响。熔池动力学模型中采用气体-粉末流动模型为颗粒源提供合理的出口速度、焦距和焦点半径,解决了熔池动力学模拟得到的粉末流运动状态难以再现实际情况的困难。此外,还进行了相关实验来验证所开发模型的准确性。粉末流的预测参数与实验一致,预测熔池尺寸的偏差小于10%。还揭示了熔池内部的传热传质现象。此外,球形孔隙缺陷的最大尺寸预计为18.6µm,与显微镜观察相比,低估了7%。总之,所开发的数值模型可以增加和改进DED过程的机器学习建模的训练样本。
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引用次数: 0
Architecture-driven Physics-informed Deep Learning for Temperature Prediction in Laser Powder Bed Fusion Additive Manufacturing with Limited Data 结构驱动的物理信息深度学习用于有限数据的激光粉末床聚变增材制造中的温度预测
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-03-30 DOI: 10.1115/1.4062237
Suyog Ghungrad, Meysam Faegh, B. Gould, S. Wolff, Azadeh Haghighi
Physics-informed deep learning (PIDL) is one of the emerging topics in additive manufacturing (AM). However, the success of previous PIDL approaches is generally significantly dependent on the existence of massive datasets. As the data collection in AM is usually challenging, a novel Architecture-driven PIDL structure named APIDL based on the deep unfolding approach for limited data scenarios has been proposed in the current study for predicting thermal history in the laser powder bed fusion process. The connections in this machine learning architecture are inspired by iterative thermal model equations. In other words, each iteration of the thermal model is mapped to a layer of the neural network. The hyper-parameters of the APIDL model are tuned, and its performance is analyzed. The APIDL for 1000 points with 80:20 split ratio achieves a testing mean absolute percentage error (MAPE) of 2.8% and R2 value of 0.936. The APIDL is compared with the artificial neural network, extra trees regressor (ETR), support vector regressor, and long short-term memory algorithms. It was shown that the proposed APIDL model outperforms the others. The MAPE and R2 of APIDL are 55.7% lower and 15.6% higher than the ETR, which had the best performance among other pure ML models.
物理知情深度学习(PIDL)是增材制造领域的新兴课题之一。然而,以前PIDL方法的成功通常在很大程度上取决于海量数据集的存在。由于AM中的数据收集通常具有挑战性,在当前的研究中,基于有限数据场景的深度展开方法,提出了一种新的架构驱动的PIDL结构APIDL,用于预测激光粉末床聚变过程中的热历史。这种机器学习架构中的连接受到迭代热模型方程的启发。换句话说,热模型的每次迭代都被映射到神经网络的一层。对APIDL模型的超参数进行了调整,并对其性能进行了分析。对于具有80:20分割比的1000个点,APIDL实现了2.8%的测试平均绝对百分比误差(MAPE)和0.936的R2值。将APIDL与人工神经网络、额外树回归器(ETR)、支持向量回归器和长短期记忆算法进行了比较。结果表明,所提出的APIDL模型优于其他模型。APIDL的MAPE和R2分别比ETR低55.7%和15.6%,在其他纯ML模型中性能最好。
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引用次数: 0
Nanoengineered Laser Shock Processing via Pulse Shaping for Nanostructuring in Metals: Multiscale simulations and experiments 金属纳米结构的脉冲成形纳米工程激光冲击处理:多尺度模拟与实验
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-03-29 DOI: 10.1115/1.4062234
Seng Xiang, Xingtao Liu, Li-cong An, Haozheng J. Qu, G. Cheng
Modulating the heating and cooling during plastic deformation has been critical to control the microstructure and phase change in metals. During laser shock peening under optimal elevated temperatures, high-density dislocations and nanoprecipitates can be generated to greatly enhance material strength and fatigue life in metals. In this paper, we propose a general methodology to modulate the heating and cooling during laser shock processing via temporal pulse shaping, namely dual pulse laser shock peening (DP-LSP), which combines both ultrafast-heating and laser shock peening in one operation to generate desired microstructure and mechanical property. Single pulse LSP was able to remelt large second phase precipitates due to fast cooling, resulting in smaller grains (500nm), while using DP-LSP with appropriate pulse durations, dynamic precipitation effects can generate nanosized (30nm) intermetallic phase Al3Ti with high density. By generation of grain size refinement, high density nanoscale precipitates, and dislocations, the yield strength increase by 18% and 102% compared with single pulse processing, and original sample respectively. A phase-field model (PFM) and multiscale dislocation dynamics (MDD) were applied to study dislocation dynamics and nanoprecipitation generation during DP-LSP, and their interaction. The work provides a basis for controlling microstructure by DP-LSP to enhance mechanical properties in metals.
调节塑性变形过程中的加热和冷却对于控制金属的微观组织和相变化至关重要。在最佳高温条件下,激光冲击强化可以产生高密度位错和纳米沉淀,从而大大提高材料强度和疲劳寿命。在本文中,我们提出了一种通过时间脉冲整形来调节激光冲击加工过程中的加热和冷却的通用方法,即双脉冲激光冲击强化(DP-LSP),它将超快加热和激光冲击强化在一次操作中结合起来,以产生所需的微观组织和力学性能。单脉冲LSP由于冷却速度快,能够重熔较大的第二相析出物,得到较小的晶粒(500nm),而采用适当脉冲持续时间的DP-LSP,动态析出效应可以生成纳米级(30nm)高密度的金属间相Al3Ti。通过晶粒细化、高密度纳米级析出和位错的产生,与单脉冲处理和原始样品相比,屈服强度分别提高了18%和102%。采用相场模型(PFM)和多尺度位错动力学(MDD)研究了DP-LSP过程中位错动力学和纳米沉淀的产生及其相互作用。该工作为通过DP-LSP控制微观组织以提高金属的力学性能提供了依据。
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引用次数: 0
Multi-agent Reinforcement Learning Method for Disassembly Sequential Task Optimization Based on Human-Robot Collaborative Disassembly in Electric Vehicle Battery Recycling 基于人机协同拆卸的电动汽车电池回收中拆卸顺序任务优化的多智能体强化学习方法
IF 4 3区 工程技术 Q3 ENGINEERING, MANUFACTURING Pub Date : 2023-03-29 DOI: 10.1115/1.4062235
Jinhua Xiao, Jiaxu Gao, N. Anwer, B. Eynard
With the wide application of new electric vehicle (EV) battery in various industrial fields, it is important to establish a systematic intelligent battery recycling system that can be used to find out the resource wastes and environmental impacts for the retired EV battery. By combining the disassembly and echelon utilization of EV battery recycling in the re-manufacturing fields, human-robot collaboration (HRC) disassembly method can be used to solve many huge challenges about the efficiency and safety of retired EV battery recycling. In order to find out the common problems in the human-robot collaboration disassembly process of EV battery recycling, a dynamic disassembly process optimization method based on Multi-Agent Reinforcement Learning (MARL) algorithm is proposed. Furthermore, it is necessary to disassemble the EV battery disassembly task trajectory based on human-robot collaboration disassembly task in 2D planar, which can be used to acquire the optimal disassembly paths in the same disassembly planar combining the Q-learning algorithm. The disassembly task sequence can be completed through standard trajectory matching. Finally the feasibility of the method is verified by disassembly operations for a specific battery module case.
随着新型电动汽车电池在各个工业领域的广泛应用,建立一个系统的智能电池回收系统来找出退役电动汽车电池的资源浪费和环境影响具有重要意义。通过将电动汽车电池回收在再制造领域的拆解和梯次利用相结合,人机协作拆解方法可以解决退役电动汽车电池循环利用效率和安全性方面的许多巨大挑战。为了找出电动汽车电池回收过程中人机协同拆卸过程中的常见问题,提出了一种基于多智能体强化学习算法的动态拆卸过程优化方法。此外,有必要在二维平面中基于人机协同拆卸任务对电动汽车电池拆卸任务轨迹进行拆卸,结合Q学习算法可以获得同一拆卸平面中的最优拆卸路径。拆卸任务序列可以通过标准轨迹匹配来完成。最后通过对具体电池模块壳体的拆卸操作验证了该方法的可行性。
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引用次数: 4
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