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Velocity Measurement of Gas–Liquid Slug Flows Using Multichannel Ultrasonic Doppler Sensor System 利用多通道超声多普勒传感器系统测量气液蛞蝓流的速度
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485430
Lusheng Zhai;Junxi Liu;Bo Xu;Yukun Huang;Ningde Jin
Horizontal gas-liquid slug flows are widely encountered in important industrial processes. Bubble velocity measurement is of great significance for understanding the heat/mass transfer and flow pattern transitions, and thus optimizing the industrial processes. Multiscale bubbles in slug flow are characterized by complicated interactions and thus exhibit intricate transient behaviors, making the velocity measurement exceedingly challenging. In this study, a multichannel ultrasonic Doppler sensor (MCUDS) is proposed to measure the bubble velocities in gas-liquid slug flows. The MCUDS features region-focused characteristics and thus yields high sensitivity at different measurement depths. A field programmable gate array (FPGA)-based measurement system is designed to generate pulse ultrasonic signals and implement rapid and stable data acquisition, processing, and transmission. A Taylor bubble tracking method based on the effective information ratio is proposed to measure the velocities of the nose and tail of Taylor bubbles. Doppler pulse repetition method (DPRM) with a sliding window is combined with the expanded autocorrelation (EAC) algorithm to derive the Doppler shift. The research results indicate that integrating a sliding window into the DPRM effectively improves the temporal resolution of bubble velocity measurements, thereby accurately constructing the spatiotemporal distribution of the velocity vectors of dispersed bubbles. This allows for the revelation of the complex motion processes of bubbles and the slug aeration characteristics under different gas-liquid flow conditions.
在重要的工业流程中,会广泛遇到水平气液悬浮流。气泡速度测量对于了解热量/质量传递和流动模式转换,进而优化工业流程具有重要意义。蛞蝓流中的多尺度气泡具有复杂的相互作用,因此表现出错综复杂的瞬态行为,这使得速度测量极具挑战性。本研究提出了一种多通道超声多普勒传感器(MCUDS),用于测量气液蛞蝓流中的气泡速度。MCUDS 具有区域聚焦特性,因此在不同测量深度下都能产生高灵敏度。设计了一种基于现场可编程门阵列 (FPGA) 的测量系统,用于生成脉冲超声波信号,并实现快速稳定的数据采集、处理和传输。提出了一种基于有效信息比的泰勒气泡跟踪方法,用于测量泰勒气泡头部和尾部的速度。采用滑动窗口的多普勒脉冲重复法(DPRM)与扩展自相关(EAC)算法相结合,得出多普勒频移。研究结果表明,在 DPRM 中加入滑动窗口可有效提高气泡速度测量的时间分辨率,从而准确构建分散气泡速度矢量的时空分布。这样就能揭示气泡的复杂运动过程以及不同气液流动条件下的蛞蝓曝气特性。
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引用次数: 0
Complex Surface Electromyography Signal Gesture Recognition Based on Multipathway Featured Scale Convolutional Neural Network 基于多通道特征尺度卷积神经网络的复杂表面肌电信号手势识别
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485448
Tie Liu;Dianchun Bai;Le Ma;Qiang Du;Hiroshi Yokoi
Surface electromyography-based gesture recognition and prosthetic hand control using deep learning (DL) have become increasingly significant in the field of human-computer interaction. This study aims to enhance the control of prosthetic hands driven by complex gestures, addressing the challenge of low-resolution gesture differentiation caused by the coupling and superposition of surface electromyography signals in DL models. We propose a DL-based framework for the recognition of complex surface electromyography signals, utilizing a multipathway approach to acquire raw surface electromyography signals, process them in the time-frequency domain, and extract features using multiscale convolutional networks. The processed surface electromyography features are then analyzed in parallel to enhance accuracy. This method effectively processes multiple signals concurrently and extracts diverse feature sets. By collecting data from six channels, it achieves an 88.56% recognition rate for 16 complex hand gestures, enabling control of ten distinct prosthetic hand movements. By leveraging multidimensional continuous surface electromyography images, we have developed a feature model that resolves the issues of signal coupling and superposition in multichannel surface electromyography data, allowing for precise control of prosthetic hand movements.
基于表面肌电图的手势识别和使用深度学习(DL)的假手控制在人机交互领域变得越来越重要。本研究旨在增强由复杂手势驱动的假手控制,解决 DL 模型中表面肌电信号的耦合和叠加导致的低分辨率手势区分难题。我们提出了一种基于 DL 的复杂表面肌电信号识别框架,利用多途径方法获取原始表面肌电信号,在时频域对其进行处理,并使用多尺度卷积网络提取特征。然后对处理后的表面肌电图特征进行并行分析,以提高准确性。这种方法能有效地同时处理多个信号,并提取不同的特征集。通过收集来自六个通道的数据,它对 16 种复杂手势的识别率达到了 88.56%,能够控制十种不同的假手动作。通过利用多维连续表面肌电图图像,我们建立了一个特征模型,解决了多通道表面肌电图数据中的信号耦合和叠加问题,从而实现了对假手动作的精确控制。
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引用次数: 0
A Detection Method for a Series Arc Fault Based on the Inevitable DC Component Due to the Arcing Process’s Asymmetry 基于电弧过程不对称导致的不可避免的直流分量的串联电弧故障检测方法
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485401
Kai Zhou;Yang Jiao;Qing Chen;Hongbin Li;Tong Wu;Zemin Qu
Due to the great diversity of loads in low-voltage systems, the detection based on characteristic parameters of the current often confuses series arc faults (SAFs) with complex loads. To address this issue, an SAF detection method is proposed based on the inevitable dc component. First, comprehensive analyses, as well as observations, are made on the electrode-arcing-current asymmetry (EACA) to demonstrate that an inevitable dc component is inevitably induced during an SAF. Then, a dc-related dominated index and several asymmetry-related supplemental indices are gathered to form a feature set with strong generality. Afterward, a specific scheme is developed based on the uni-period state evaluation and the multiperiod fault judgment to reduce the false detection, where the eXtreme gradient boosting (XGBoost) algorithm is employed as a classifier. After that, experiments are made to verify the proposed method’s validity. Finally, with monitored samples used to construct an ultrageneral testing set, simulations are conducted to prove its superiority in generality.
由于低压系统中的负载种类繁多,基于电流特征参数的检测往往会混淆复杂负载的串联电弧故障(SAF)。针对这一问题,我们提出了一种基于不可避免的直流分量的 SAF 检测方法。首先,对电弧电流不对称性(EACA)进行了全面分析和观测,以证明在 SAF 期间不可避免地会诱发直流分量。然后,收集了一个与直流相关的主导指数和几个与不对称相关的补充指数,形成了一个通用性很强的特征集。之后,在单周期状态评估和多周期故障判断的基础上开发了一种特定方案来减少误检测,其中采用了极端梯度提升(XGBoost)算法作为分类器。随后,实验验证了所提方法的有效性。最后,利用监测到的样本构建超通用测试集,并进行模拟以证明其通用性的优越性。
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引用次数: 0
Self-Mixing Interferometry on Long Distance: Theory and Experimental Validation 长距离自混合干涉测量:理论与实验验证
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485399
Alfred Albert;Silvano Donati;San-Liang Lee
We consider the operation of a self-mixing interferometer on distances larger than the laboratory scale, that is, tens to hundreds of meters, and develop for the first time the theoretical analysis of SMI performances in the near and far field (FF), presenting results about signal amplitude (AM), SNR, C factor, spot size, and linewidth. Theory is also valid for the realistic case of an elliptical laser spot. Thereafter, we compare the theoretical findings with experimental data measured on white paper target using a diode laser SMI operating at 1550 nm, with a SNR =3.6 at 12-m distance and find good agreement. These results open the way to long stand-off vibration, displacement, and distance/velocity measurements.
我们考虑了自混频干涉仪在大于实验室尺度的距离(即几十米到几百米)上的运行,并首次对自混频干涉仪在近场和远场(FF)的性能进行了理论分析,给出了有关信号幅度(AM)、信噪比、C 因子、光斑大小和线宽的结果。理论也适用于椭圆形激光光斑的实际情况。随后,我们将理论结果与使用二极管激光器 SMI(工作波长为 1550 nm,信噪比为 3.6,距离为 12 米)在白纸目标上测量的实验数据进行了比较,结果发现两者吻合得很好。这些结果为远距离振动、位移和距离/速度测量开辟了道路。
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引用次数: 0
A Novel Gravity Disturbance Compensation Inertial Navigation Method Based on Newtonian Mechanics 基于牛顿力学的新型重力干扰补偿惯性导航方法
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485437
Kaixin Luo;Ruihang Yu;Meiping Wu;Juliang Cao;Yulong Huang
With the continuous improvement of the accuracy of inertial devices and systems, the effects of gravity disturbance on autonomous inertial navigation system (INS) calculations cannot be overlooked. The traditional gravity disturbance compensation method directly introduces it into the INS calculation link, but the errors of gravity disturbance will lead to irreversible INS calculation errors, ultimately rendering the traditional compensation method ineffective. In this article, a new gravity disturbance compensation method for INS is proposed based on Newtonian mechanics. The INS calculation errors caused by horizontal gravity disturbance are directly corrected in the navigation system in a direct manner, which avoids coupling attitude calculation errors. The physical quantity of direct compensation is derived, and the influences of different compensation periods on the algorithm are tested. The effectiveness of the proposed method is validated using various sources of gravity disturbance. Both simulation and experimental results demonstrate that our method can effectively mitigate the influence of gravity disturbances on high-precision INSs.
随着惯性设备和系统精度的不断提高,重力干扰对自主惯性导航系统(INS)计算的影响不容忽视。传统的重力扰动补偿方法直接将其引入 INS 计算环节,但重力扰动的误差会导致不可逆的 INS 计算误差,最终导致传统补偿方法失效。本文基于牛顿力学提出了一种新的 INS 重力扰动补偿方法。以直接方式在导航系统中直接修正由水平重力扰动引起的 INS 计算误差,避免了耦合姿态计算误差。推导了直接补偿的物理量,并测试了不同补偿周期对算法的影响。利用各种重力干扰源验证了所提方法的有效性。模拟和实验结果表明,我们的方法可以有效减轻重力干扰对高精度 INS 的影响。
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引用次数: 0
RGB-D Vision Navigation via Motion Saliency Measurement and Twin Reprojection Optimization in Complex Dynamic Scenes 在复杂动态场景中通过运动显著性测量和双子重投影优化实现 RGB-D 视觉导航
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485442
Chao Sun;Xing Wu;Changyin Sun
Localization in an unexplored environment is a fundamental capability for robotic vision navigation. However, due to the static world assumption, it still suffers the impoverishment of robustness and accuracy in complex dynamic workspaces. Moving objects, with indeterminate motion status in dynamic scenarios, usually increase the difficulty and complexity to the localization of the robotic vehicles. To address this problem, a robust and real-time RGB-D vision navigation system based on motion saliency measurement (MSM) and twin reprojection (TR) optimization is proposed to allow accurate localization for the robotic vehicles under complex dynamic scenes. Firstly, a novel saliency-induced dense motion removal (SDMR) method is developed to detect and eliminate the dynamic regions in RGB-D inputs, which can effectively filter out the outlier data that are associated with the moving objects. Then, a robust matching strategy for edge drawing lines (EDLines) feature is devised to acquire fine line inliers by constructing keypoint correspondence. Furthermore, the TR error is built by depth measurement for the line features. It is incorporated into a new error optimization function to achieve optimal pose estimation. The experimental results demonstrate that the SDMR can accurately detect dynamic objects and eliminate movement regions in complex dynamic scenarios. The proposed navigation system proves to attain at least 26% improvement of localization accuracy over other advanced dynamic navigation solutions. Test code is available on https://github.com/SunIMLab/TL-REE.
在未知环境中定位是机器人视觉导航的一项基本能力。然而,由于存在静态世界假设,在复杂的动态工作空间中,其鲁棒性和准确性仍然存在缺陷。在动态场景中,移动物体的运动状态不确定,通常会增加机器人车辆定位的难度和复杂性。为解决这一问题,我们提出了一种基于运动显著性测量(MSM)和孪生重投影(TR)优化的鲁棒实时 RGB-D 视觉导航系统,以实现复杂动态场景下机器人车辆的精确定位。首先,开发了一种新颖的运动显著性诱导密集运动去除(SDMR)方法,用于检测和消除 RGB-D 输入中的动态区域,从而有效过滤掉与运动物体相关的离群数据。然后,针对边缘画线(EDLines)特征设计了一种鲁棒匹配策略,通过构建关键点对应关系来获取细线异常值。此外,还通过对线条特征的深度测量来建立 TR 误差。它被纳入一个新的误差优化函数,以实现最佳姿态估计。实验结果表明,SDMR 可以在复杂的动态场景中准确检测动态物体并消除运动区域。与其他先进的动态导航解决方案相比,建议的导航系统至少提高了 26% 的定位精度。测试代码可在 https://github.com/SunIMLab/TL-REE 上获取。
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引用次数: 0
WiFaKey: Generating Cryptographic Keys From Face in the Wild WiFaKey:从野生人脸生成加密密钥
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485436
Xingbo Dong;Hui Zhang;Yen Lung Lai;Zhe Jin;Junduan Huang;Wenxiong Kang;Andrew Beng Jin Teoh
Deriving a unique cryptographic key from biometric measurements is a challenging task due to the existing noise gap between the biometric measurements and error correction coding. Additionally, privacy and security concerns arise as biometric measurements are inherently linked to the user. Bio-cryptosystems represent a key branch of solutions aimed at addressing these issues. However, many existing bio-cryptosystems rely on handcrafted feature extractors and error correction codes (ECC), often leading to performance degradation. To address these challenges and improve the reliability of biometric measurements, we propose a novel biometric cryptosystem (BC) named WiFaKey, for generating cryptographic keys from face in unconstrained settings. Specifically, WiFaKey first introduces an adaptive random masking-driven feature transformation pipeline, AdaMTrans. AdaMTrans effectively quantizes and binarizes real-valued features and incorporates an adaptive random masking scheme to align the bit error rate (BER) with error correction requirements, thereby mitigating the noise gap. Besides, WiFaKey incorporates a supervised learning-based neural decoding scheme called neural-MS decoder, which delivers a more robust error correction performance with less iteration than nonlearning decoders, thereby alleviating the performance degradation. We evaluated WiFaKey using widely adopted face feature extractors on six large unconstrained and two constrained datasets. On the labeled faces in the wild database (LFW) dataset, WiFaKey achieved an average genuine match rate (GMR) of 85.45% and 85.20% at a 0% false match rate (FMR) for MagFace and AdaFace features, respectively. Our comprehensive comparative analysis shows a significant performance improvement of WiFaKey. The source code of our work is available at github.com/xingbod/WiFaKey.
由于生物识别测量和纠错编码之间存在噪声差距,因此从生物识别测量中提取唯一的加密密钥是一项具有挑战性的任务。此外,由于生物识别测量与用户之间存在固有联系,隐私和安全问题也随之而来。生物密码系统是旨在解决这些问题的解决方案的一个重要分支。然而,许多现有的生物密码系统都依赖于手工制作的特征提取器和纠错码(ECC),这往往会导致性能下降。为了应对这些挑战并提高生物识别测量的可靠性,我们提出了一种名为 WiFaKey 的新型生物识别密码系统(BC),用于在不受约束的环境下从人脸生成密码密钥。具体来说,WiFaKey 首先引入了一个自适应随机掩码驱动的特征转换管道 AdaMTrans。AdaMTrans 能有效地对实值特征进行量化和二值化处理,并采用自适应随机屏蔽方案,使误码率(BER)与纠错要求保持一致,从而减少噪声差距。此外,WiFaKey 还采用了一种基于监督学习的神经解码方案(称为神经-MS 解码器),与非学习型解码器相比,它能以更少的迭代次数提供更稳健的纠错性能,从而缓解性能下降的问题。我们使用广泛采用的人脸特征提取器在六个大型无约束数据集和两个有约束数据集上对 WiFaKey 进行了评估。在野生数据库(LFW)的标注人脸数据集上,WiFaKey 的 MagFace 和 AdaFace 特征的平均真实匹配率(GMR)分别为 85.45% 和 85.20%,错误匹配率(FMR)为 0%。我们的综合比较分析表明,WiFaKey 的性能有了显著提高。我们工作的源代码可在 github.com/xingbod/WiFaKey 上获取。
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引用次数: 0
On Grain Security by Temperature Interpolation: A Deep Learning Method for Comprehensive Data Fusion in Smart Granaries 通过温度插值实现谷物安全:用于智能粮仓综合数据融合的深度学习方法
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485435
Zhongke Qu;Ke Yang;Yue Li;Xuemei Jiang;Yang Zhang;Yanyan Zhao;Wenfei Wu;Yuan Gao;Zhaolin Gu;Zhibin Zhao
As an indicator of grain safety, grain temperature data assumes great importance in the analysis of grain storage conditions and the decision-making of preventive measures such as ventilation and cooling. However, obtaining a thorough picture of grain temperature distribution via grain IoT with sensors deployed in the granary remains a challenge, given numerous data gaps across various areas due to insufficient coverage of the sensor network that fails to encompass the entire granary. Interpolation of grain temperature data, in this regard, is able to fill in the “unsensored” areas that are vacant in the records of data. Yet little literature is found in the frontier scholarship of grain temperature interpolation. To fill this noticeable niche, this study develops a novel data fusion interpolation model named convolutional neural network-attention-multilayer perceptron neural network (CAMNN) featuring an integration of convolutional neural network (CNN), attention mechanism, and multilayer perceptron (MLP). CNN is used to capture local spatial features of the temperature data, the attention mechanism enables the location of key and sensitive temperature areas, and MLP is incorporated for deep feature fusion. Performances of the proposed model are evaluated in a bin granary located in Shaanxi, China, and further validated in a larger bin granary of different storage types situated in Ningxia, China. Comparative assessments are conducted with five machine learning and deep learning (DL) models. Results indicate that CAMNN outperforms the other models, with a mean absolute error (MAE) of 0.5251 and a mean square error (mse) of 1.0881, demonstrating robust cross-context applicability across bin granaries varying in terms of sizes, storage types, and climatic zones.
作为谷物安全的一项指标,谷物温度数据在谷物储存条件分析以及通风和冷却等预防措施决策中具有重要意义。然而,由于传感器网络覆盖范围不足,无法覆盖整个粮仓,导致不同区域存在大量数据缺口,因此通过部署在粮仓中的传感器进行粮食物联网来全面了解粮食温度分布情况仍然是一项挑战。在这方面,对谷物温度数据进行插值能够填补数据记录中的 "未删减 "区域。然而,在谷物温度插值的前沿学术领域却鲜有文献。为了填补这一空白,本研究开发了一种新颖的数据融合插值模型,命名为卷积神经网络-注意力-多层感知器神经网络(CAMNN),其特点是整合了卷积神经网络(CNN)、注意力机制和多层感知器(MLP)。卷积神经网络用于捕捉温度数据的局部空间特征,注意力机制可定位关键和敏感的温度区域,而 MLP 则用于深度特征融合。所提模型的性能在中国陕西的一个仓廒中进行了评估,并在中国宁夏不同存储类型的更大仓廒中进行了进一步验证。与五种机器学习和深度学习(DL)模型进行了比较评估。结果表明,CAMNN 的表现优于其他模型,其平均绝对误差 (MAE) 为 0.5251,平均平方误差 (mse) 为 1.0881,这表明它在不同规模、存储类型和气候带的仓廒中具有强大的跨环境适用性。
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引用次数: 0
Application of a Single-Crystal CVD Diamond Detector for Fast Neutron Measurement in High Dose and Mixed Radiation Fields 在高剂量和混合辐射场中应用单晶 CVD 金刚石探测器进行快速中子测量
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3481590
Makoto I. Kobayashi;Sachiko Yoshihashi;Kunihiro Ogawa;Mitsutaka Isobe;Tsukasa Aso;Masanori Hara;Siriyaporn Sangaroon;Sachie Kusaka;Shingo Tamaki;Isao Murata;Sho Toyama;Misako Miwa;Shigeo Matsuyama;Masaki Osakabe
This article presents the method to evaluate the fast neutron energy spectrum using the single-crystal chemical vapor deposition (CVD) diamond detector to be applicable on the radiation monitoring in advanced scientific/engineering systems usually characterized with mixed and high-dose radiation field. The pulse shape discrimination (PSD) based on the shape and the width of a pulse was applied to extract events, in which fast neutron hits at the specific depth of the single-crystal diamond. Unfolding of the measured spectrum for extracted pulses could deduce the neutron energy spectrum. Experiments using monoenergetic neutron sources demonstrated the reliable capability of this method to evaluate the neutron energy spectrum quantitatively.
本文介绍了利用单晶化学气相沉积(CVD)金刚石探测器评估快中子能谱的方法,该方法适用于通常具有混合和高剂量辐射场特征的先进科学/工程系统的辐射监测。基于脉冲形状和宽度的脉冲形状判别(PSD)被用于提取快中子击中单晶金刚石特定深度的事件。对提取脉冲的测量频谱进行展开,可以推断出中子能谱。使用单能中子源进行的实验证明,这种方法具有定量评估中子能谱的可靠能力。
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引用次数: 0
The Active Visual Sensing Methods for Robotic Welding: Review, Tutorial, and Prospect 机器人焊接的主动视觉传感方法:回顾、教程与展望
IF 5.6 2区 工程技术 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC Pub Date : 2024-10-23 DOI: 10.1109/TIM.2024.3485460
ZhenZhou Wang
The visual sensing system is one of the most important parts of the welding robots to realize intelligent and autonomous welding. The active visual sensing methods have been widely adopted in robotic welding because of their higher accuracies compared to the passive visual sensing methods. In this article, a comprehensive review of the active visual sensing methods for robotic welding is given. According to their uses, the state-of-the-art active visual sensing methods are divided into four categories: seam tracking, weld bead defect detection, 3-D weld pool geometry measurement, and welding path planning. First, the principles of these active visual sensing methods are reviewed. Then, a tutorial on the 3-D calibration methods for the active visual sensing systems used in intelligent welding robots is given to fill the gaps in the related fields. At last, the reviewed active visual sensing methods are compared and the prospects are given based on their advantages and disadvantages.
视觉传感系统是焊接机器人实现智能和自主焊接的最重要部分之一。与被动视觉传感方法相比,主动视觉传感方法具有更高的精确度,因此在机器人焊接中被广泛采用。本文全面综述了用于机器人焊接的主动视觉传感方法。根据其用途,最先进的主动视觉传感方法可分为四类:焊缝跟踪、焊缝缺陷检测、三维焊池几何形状测量和焊接路径规划。首先,回顾了这些主动视觉传感方法的原理。然后,介绍了用于智能焊接机器人的主动视觉传感系统的三维校准方法,以填补相关领域的空白。最后,比较了所综述的主动视觉传感方法,并根据其优缺点提出了展望。
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引用次数: 0
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IEEE Transactions on Instrumentation and Measurement
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