针对夜间低光照场景下目标特征提取困难和跟踪不稳定的问题,提出了基于自编码器结构及改进Bytetrack的多目标行人检测及跟踪算法。在检测阶段,基于YOLOX(you only look once X)搭建多任务自编码变换模型框架,以一种自监督的方式考虑物...针对夜间低光照场景下目标特征提取困难和跟踪不稳定的问题,提出了基于自编码器结构及改进Bytetrack的多目标行人检测及跟踪算法。在检测阶段,基于YOLOX(you only look once X)搭建多任务自编码变换模型框架,以一种自监督的方式考虑物理噪声模型和图像信号处理(image signal processing,ISP)的过程,通过对真实光照退化变换过程进行编码与解码学习内在视觉结构,并基于这种表示通过解码边界框坐标与类实现目标检测任务。为了抑制背景噪声的干扰,在目标解码器颈部网络引入自适应特征融合模块ASFF。跟踪阶段,基于Bytetrack算法进行改进,将基于Tranformer重识别网络提取到的外观嵌入信息与NSA卡尔曼滤波获得的运动信息通过自适应加权的方法完成数据关联,并通过Byte两次匹配的算法完成夜间行人的跟踪。在自建夜间行人检测数据集上测试检测模型的泛化能力,mAP@0.5达到了94.9%,结果表明本文的退化变换过程符合现实条件,具有良好的泛化能力。最后通过自建夜间行人跟踪数据集验证多目标跟踪性能,实验结果表明,本文提出的夜间低光照行人多目标跟踪算法MOTA(multiple object tracking accuracy)为89.55%,IDF1(identity F1 score)为88.34%,IDs(ID switches)为15。与基准方法Bytetrack相比,MOTA提高了10.72%,IDF1提高了6.19%,IDs减少了50%。结果表明,本文提出的基于自编码结构及改进Bytetrack的多目标跟踪算法可以有效解决在夜间低光照场景下行人跟踪困难的问题。展开更多
In this paper,a non-contact auto-focusing method is proposed for the essential function of auto-focusing in mobile devices.Firstly,we introduce an effective target detection method combining the 3-frame difference alg...In this paper,a non-contact auto-focusing method is proposed for the essential function of auto-focusing in mobile devices.Firstly,we introduce an effective target detection method combining the 3-frame difference algorithm and Gauss mixture model,which is robust for complex and changing background.Secondly,a stable tracking method is proposed using the local binary patter feature and camshift tracker.Auto-focusing is achieved by using the coordinate obtained during the detection and tracking procedure.Experiments show that the proposed method can deal with complex and changing background.When there exist multiple moving objects,the proposed method also has good detection and tracking performance.The proposed method implements high efficiency,which means it can be easily used in real mobile device systems.展开更多
In the wireless guidance system, the signals that receiver received has obvious Doppler shift for the high dynamic characteristic of the carrier. A new solution of carrier frequency tracking loop with frequency modify...In the wireless guidance system, the signals that receiver received has obvious Doppler shift for the high dynamic characteristic of the carrier. A new solution of carrier frequency tracking loop with frequency modifying system is put forward. The characteristic of cross product auto frequency control and the second order loop filter in this loop are analyzed. The simulation shows that this loop can accomplish frequency tracking well in high dynamic circumstance.展开更多
The development of welding robots suitable for specially unstructured working enviroments has been become an important development direction of industrial robot application because large-scale welding structures have ...The development of welding robots suitable for specially unstructured working enviroments has been become an important development direction of industrial robot application because large-scale welding structures have been used more and more widely in modern industry. In this paper, an intelligent mobile robot for welding of ship deck with the function of autosearching weld line was presented. A wheeled motion mechanism and a cross adjustment slider are used for the welding robot body. A sensing system based on laser-PSD （position sensitive detector） displacement sensor was developed to obtain two dimensional deviation signals during seam tracking. A full-digital control system based on DSP and CPLD has also been realized to implement complex and high-performance control algorithms. Furthermore, the system has still the function of auto-searching weld line according to the characteristics information of weld groove and adjusting posture itself to the desired status preparing for welding. The experiment of auto-searching welding line shows that the robot has high tracing accuracy, and can satisfy the requirement of practical welding project.展开更多
文摘针对夜间低光照场景下目标特征提取困难和跟踪不稳定的问题,提出了基于自编码器结构及改进Bytetrack的多目标行人检测及跟踪算法。在检测阶段,基于YOLOX(you only look once X)搭建多任务自编码变换模型框架,以一种自监督的方式考虑物理噪声模型和图像信号处理(image signal processing,ISP)的过程,通过对真实光照退化变换过程进行编码与解码学习内在视觉结构,并基于这种表示通过解码边界框坐标与类实现目标检测任务。为了抑制背景噪声的干扰,在目标解码器颈部网络引入自适应特征融合模块ASFF。跟踪阶段,基于Bytetrack算法进行改进,将基于Tranformer重识别网络提取到的外观嵌入信息与NSA卡尔曼滤波获得的运动信息通过自适应加权的方法完成数据关联,并通过Byte两次匹配的算法完成夜间行人的跟踪。在自建夜间行人检测数据集上测试检测模型的泛化能力,mAP@0.5达到了94.9%,结果表明本文的退化变换过程符合现实条件,具有良好的泛化能力。最后通过自建夜间行人跟踪数据集验证多目标跟踪性能,实验结果表明,本文提出的夜间低光照行人多目标跟踪算法MOTA(multiple object tracking accuracy)为89.55%,IDF1(identity F1 score)为88.34%,IDs(ID switches)为15。与基准方法Bytetrack相比,MOTA提高了10.72%,IDF1提高了6.19%,IDs减少了50%。结果表明,本文提出的基于自编码结构及改进Bytetrack的多目标跟踪算法可以有效解决在夜间低光照场景下行人跟踪困难的问题。
基金supported by ZTE Industry-Academia-Research Cooperation Funds
文摘In this paper,a non-contact auto-focusing method is proposed for the essential function of auto-focusing in mobile devices.Firstly,we introduce an effective target detection method combining the 3-frame difference algorithm and Gauss mixture model,which is robust for complex and changing background.Secondly,a stable tracking method is proposed using the local binary patter feature and camshift tracker.Auto-focusing is achieved by using the coordinate obtained during the detection and tracking procedure.Experiments show that the proposed method can deal with complex and changing background.When there exist multiple moving objects,the proposed method also has good detection and tracking performance.The proposed method implements high efficiency,which means it can be easily used in real mobile device systems.
文摘In the wireless guidance system, the signals that receiver received has obvious Doppler shift for the high dynamic characteristic of the carrier. A new solution of carrier frequency tracking loop with frequency modifying system is put forward. The characteristic of cross product auto frequency control and the second order loop filter in this loop are analyzed. The simulation shows that this loop can accomplish frequency tracking well in high dynamic circumstance.
文摘The development of welding robots suitable for specially unstructured working enviroments has been become an important development direction of industrial robot application because large-scale welding structures have been used more and more widely in modern industry. In this paper, an intelligent mobile robot for welding of ship deck with the function of autosearching weld line was presented. A wheeled motion mechanism and a cross adjustment slider are used for the welding robot body. A sensing system based on laser-PSD （position sensitive detector） displacement sensor was developed to obtain two dimensional deviation signals during seam tracking. A full-digital control system based on DSP and CPLD has also been realized to implement complex and high-performance control algorithms. Furthermore, the system has still the function of auto-searching weld line according to the characteristics information of weld groove and adjusting posture itself to the desired status preparing for welding. The experiment of auto-searching welding line shows that the robot has high tracing accuracy, and can satisfy the requirement of practical welding project.
