To overcome the shortcomings of the traditional passive ranging technology based on image, such as poor ranging accuracy, low reliability and complex system, a new visual passive ranging method based on re-entrant coa...To overcome the shortcomings of the traditional passive ranging technology based on image, such as poor ranging accuracy, low reliability and complex system, a new visual passive ranging method based on re-entrant coaxial optical path is presented. The target image is obtained using double cameras with coaxial optical path. Since there is imaging optical path difference between the cameras, the images are different. In comparison of the image differences, the target range could be reversed. The principle of the ranging method and the ranging model are described. The relationship among parameters in the ranging process is analyzed quantitatively. Meanwhile,the system composition and technical realization scheme are also presented. Also, the principle of the method is verified by the equivalent experiment. The experimental results show that the design scheme is correct and feasible with good robustness. Generally, the ranging error is less than 10% with good convergence. The optical path is designed in a re-entrant mode to reduce the volume and weight of the system. Through the coaxial design,the visual passive range of the targets with any posture can be obtained in real time. The system can be widely used in electro-optical countermeasure and concealed photoelectric detection.展开更多
Abstract： There is a high demand for unmanned aerial vehicle （UAV） flight stability when using vi- sion as a detection method for navigation control. To meet such demand, a new path planning meth- od for controllin...Abstract： There is a high demand for unmanned aerial vehicle （UAV） flight stability when using vi- sion as a detection method for navigation control. To meet such demand, a new path planning meth- od for controlling multi-UAVs is studied to reach multi-waypoints simultaneously under the view of visual navigation technology. A model based on the stable-shortest pythagorean-hodograph （PH） curve is established, which could not only satisfy the demands of visual navigation and control law, but also be easy to compute. Based on the model, a planning algorithm to guide multi-UAVs to reach multi-waypoints at the same time without collisions is developed. The simulation results show that the paths have shorter distance and smaller curvature than traditional methods, which could help to avoid collisions.展开更多
为了解体育支教研究的历史脉络与未来趋势,探究助力体育支教研究不断紧跟时代的研究路径,运用Cite Space 6.4.R1可视化软件对知网上检索到的“体育支教”相关文献进行可视化分析,对其关键词进行数据聚合运算。研究结果显示,体育支教领...为了解体育支教研究的历史脉络与未来趋势,探究助力体育支教研究不断紧跟时代的研究路径,运用Cite Space 6.4.R1可视化软件对知网上检索到的“体育支教”相关文献进行可视化分析,对其关键词进行数据聚合运算。研究结果显示,体育支教领域研究已经形成了有一定社会影响力的教育实施模式,但对体育支教的创新对策研究数量明显偏少,对现有的体育支教行动策略进行不断的完善发展方面有待深入研究。近几年,关于体育支教研究的前沿与趋势同乡村振兴发展有着密切联系。总体上,国内关于体育支教研究宏观角度与微观角度并存,始终围绕关键问题并紧跟国家政策变化,未来研究应扩大文献样本与数据来源,以便更全面地描绘该领域的研究现状与趋势。展开更多
基金Supported by the National Basic Research Program of China under Grant No 2014CB340102
文摘To overcome the shortcomings of the traditional passive ranging technology based on image, such as poor ranging accuracy, low reliability and complex system, a new visual passive ranging method based on re-entrant coaxial optical path is presented. The target image is obtained using double cameras with coaxial optical path. Since there is imaging optical path difference between the cameras, the images are different. In comparison of the image differences, the target range could be reversed. The principle of the ranging method and the ranging model are described. The relationship among parameters in the ranging process is analyzed quantitatively. Meanwhile,the system composition and technical realization scheme are also presented. Also, the principle of the method is verified by the equivalent experiment. The experimental results show that the design scheme is correct and feasible with good robustness. Generally, the ranging error is less than 10% with good convergence. The optical path is designed in a re-entrant mode to reduce the volume and weight of the system. Through the coaxial design,the visual passive range of the targets with any posture can be obtained in real time. The system can be widely used in electro-optical countermeasure and concealed photoelectric detection.
文摘Abstract： There is a high demand for unmanned aerial vehicle （UAV） flight stability when using vi- sion as a detection method for navigation control. To meet such demand, a new path planning meth- od for controlling multi-UAVs is studied to reach multi-waypoints simultaneously under the view of visual navigation technology. A model based on the stable-shortest pythagorean-hodograph （PH） curve is established, which could not only satisfy the demands of visual navigation and control law, but also be easy to compute. Based on the model, a planning algorithm to guide multi-UAVs to reach multi-waypoints at the same time without collisions is developed. The simulation results show that the paths have shorter distance and smaller curvature than traditional methods, which could help to avoid collisions.
文摘为了解体育支教研究的历史脉络与未来趋势,探究助力体育支教研究不断紧跟时代的研究路径,运用Cite Space 6.4.R1可视化软件对知网上检索到的“体育支教”相关文献进行可视化分析,对其关键词进行数据聚合运算。研究结果显示,体育支教领域研究已经形成了有一定社会影响力的教育实施模式,但对体育支教的创新对策研究数量明显偏少,对现有的体育支教行动策略进行不断的完善发展方面有待深入研究。近几年,关于体育支教研究的前沿与趋势同乡村振兴发展有着密切联系。总体上,国内关于体育支教研究宏观角度与微观角度并存,始终围绕关键问题并紧跟国家政策变化,未来研究应扩大文献样本与数据来源,以便更全面地描绘该领域的研究现状与趋势。
