The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave...The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave infrared wavelengths as beacon light can reduce atmospheric absorption and signal attenuation.However,there are strong non-uniformity and blind pixels in the short-wave infrared image,which makes the image distorted and leads to the decrease of spot centroid positioning accuracy.Therefore,the high-precision localization of the spot centroid of the short-wave infrared images is of great research significance.A high-precision spot centroid positioning model for short-wave infrared is proposed to correct for non-uniformity and blind pixels in short-wave infrared images and quantify the localization errors caused by the two,further model-based localization error simulations are performed,and a novel spot centroid positioning payload for satellite laser communications has been designed using the latest 640×512 planar array InGaAs shortwave infrared detector.The experimental results show that the non-uniformity of the corrected image is reduced from 7%to 0.6%,the blind pixels rejection rate reaches 100%,the frame rate can be up to 2000 Hz,and the spot centroid localization accuracy is as high as 0.1 pixel point,which realizes high-precision spot centroid localization of high-frame-frequency short-wave infrared images.展开更多
离心机是岩土工程学科开展缩尺模型试验的主要装置,被广泛应用于降雨、滑坡等工程问题。开展了一系列无约束小球运动离心试验,基于双目立体视觉原理还原小球轨迹并验证了离心超重力下质点运动的控制方程。在此基础上对离心降雨模拟进行...离心机是岩土工程学科开展缩尺模型试验的主要装置,被广泛应用于降雨、滑坡等工程问题。开展了一系列无约束小球运动离心试验,基于双目立体视觉原理还原小球轨迹并验证了离心超重力下质点运动的控制方程。在此基础上对离心降雨模拟进行数值分析并提出4项降雨均匀性指标。分析表明,质量变化与非惯性系耦合作用会使得物体受到一项额外的作用力。离心超重力下the Green Mist喷嘴模拟的降雨的空间和统计分布特征会在空气阻力和非惯性系作用下发生显著改变。降雨均匀性指标对于确定喷嘴阵列布置具有指导意义,以研究工况为例,2×2的the Green Mist喷嘴阵列沿边坡长度和宽度方向的喷嘴覆盖面积重叠率的推荐值分别为60.47%,55.36%。展开更多
基金Supported by the Short-wave Infrared Camera Systems(B025F40622024)。
文摘The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave infrared wavelengths as beacon light can reduce atmospheric absorption and signal attenuation.However,there are strong non-uniformity and blind pixels in the short-wave infrared image,which makes the image distorted and leads to the decrease of spot centroid positioning accuracy.Therefore,the high-precision localization of the spot centroid of the short-wave infrared images is of great research significance.A high-precision spot centroid positioning model for short-wave infrared is proposed to correct for non-uniformity and blind pixels in short-wave infrared images and quantify the localization errors caused by the two,further model-based localization error simulations are performed,and a novel spot centroid positioning payload for satellite laser communications has been designed using the latest 640×512 planar array InGaAs shortwave infrared detector.The experimental results show that the non-uniformity of the corrected image is reduced from 7%to 0.6%,the blind pixels rejection rate reaches 100%,the frame rate can be up to 2000 Hz,and the spot centroid localization accuracy is as high as 0.1 pixel point,which realizes high-precision spot centroid localization of high-frame-frequency short-wave infrared images.
文摘离心机是岩土工程学科开展缩尺模型试验的主要装置,被广泛应用于降雨、滑坡等工程问题。开展了一系列无约束小球运动离心试验,基于双目立体视觉原理还原小球轨迹并验证了离心超重力下质点运动的控制方程。在此基础上对离心降雨模拟进行数值分析并提出4项降雨均匀性指标。分析表明,质量变化与非惯性系耦合作用会使得物体受到一项额外的作用力。离心超重力下the Green Mist喷嘴模拟的降雨的空间和统计分布特征会在空气阻力和非惯性系作用下发生显著改变。降雨均匀性指标对于确定喷嘴阵列布置具有指导意义,以研究工况为例,2×2的the Green Mist喷嘴阵列沿边坡长度和宽度方向的喷嘴覆盖面积重叠率的推荐值分别为60.47%,55.36%。
