机器人替代人工紧固角钢塔螺栓是解决高空作业安全问题的途径之一.针对角钢塔螺栓紧固机器人的作业需求,提出了一种基于神经网络和RGB-D相机的角钢塔主材螺栓检测与定位系统,将轻量化的YOLOv5s-T网络应用于英特尔®实感™深度摄像头D...机器人替代人工紧固角钢塔螺栓是解决高空作业安全问题的途径之一.针对角钢塔螺栓紧固机器人的作业需求,提出了一种基于神经网络和RGB-D相机的角钢塔主材螺栓检测与定位系统,将轻量化的YOLOv5s-T网络应用于英特尔®实感™深度摄像头D435i采集的图像,实现了角钢塔主材螺栓的实时检测、三维定位及重新排序等功能.经实验验证,YOLOv5s-T在基本不降低均值平均精度(mean average precision,mAP)的情况下,推理速度提高约31%;用RGB-D相机测得的三维坐标计算相邻螺栓间距,平均误差小于1 mm.对主材螺栓排序算法进行验证,RGB-D相机正对螺栓组模板时,模板的正确排序率不低于95%,可快速引导6自由度机械臂末端到达螺栓紧固点.展开更多
First-principles calculations have been carried out to investigate the effects of alloying elements（Zn, Li, Y and Sc） on the electronic structure, elastic and thermal properties of Mg solid solution. The calculated ...First-principles calculations have been carried out to investigate the effects of alloying elements（Zn, Li, Y and Sc） on the electronic structure, elastic and thermal properties of Mg solid solution. The calculated cohesive energies show that Mg-Sc has the highest structural stability. The calculations of the densities of states（DOS） and electronic charge density difference indicate that Mg-Y（Sc） alloys have very strong covalent bonding due to a very strong Mg p-Y（Sc） d hybridization. The bulk modulus B, shear modulus G, Young＇s modulus E and Poisson ratio ν are derived using Voigt-Reuss-Hill（VRH） approximation. The results show that all the alloys can exhibit ductile properties at 2.77 at% R, and Mg-Zn（Li） alloys have the better ductility and plasticity. In the end, the Debye temperature and isochoric heat capacity are also calculated and discussed.展开更多
文摘机器人替代人工紧固角钢塔螺栓是解决高空作业安全问题的途径之一.针对角钢塔螺栓紧固机器人的作业需求,提出了一种基于神经网络和RGB-D相机的角钢塔主材螺栓检测与定位系统,将轻量化的YOLOv5s-T网络应用于英特尔®实感™深度摄像头D435i采集的图像,实现了角钢塔主材螺栓的实时检测、三维定位及重新排序等功能.经实验验证,YOLOv5s-T在基本不降低均值平均精度(mean average precision,mAP)的情况下,推理速度提高约31%;用RGB-D相机测得的三维坐标计算相邻螺栓间距,平均误差小于1 mm.对主材螺栓排序算法进行验证,RGB-D相机正对螺栓组模板时,模板的正确排序率不低于95%,可快速引导6自由度机械臂末端到达螺栓紧固点.
基金Funded by the National Natural Science Foundation of China(Nos.51574206,51204147 and 51274175)International Cooperation Project Supported by Ministry of Science and Technology of China(No.2014DFA50320)International Cooperation Project Supported by Shanxi Province(Nos.2013081017,2012081013)
文摘First-principles calculations have been carried out to investigate the effects of alloying elements（Zn, Li, Y and Sc） on the electronic structure, elastic and thermal properties of Mg solid solution. The calculated cohesive energies show that Mg-Sc has the highest structural stability. The calculations of the densities of states（DOS） and electronic charge density difference indicate that Mg-Y（Sc） alloys have very strong covalent bonding due to a very strong Mg p-Y（Sc） d hybridization. The bulk modulus B, shear modulus G, Young＇s modulus E and Poisson ratio ν are derived using Voigt-Reuss-Hill（VRH） approximation. The results show that all the alloys can exhibit ductile properties at 2.77 at% R, and Mg-Zn（Li） alloys have the better ductility and plasticity. In the end, the Debye temperature and isochoric heat capacity are also calculated and discussed.
