A hybrid Jacobian control for uncalibrated robot visual servoing

This paper focuses on the visual servo control of an uncalibrated robotic arm with an eye-in-hand camera. Without a prior knowledge of the kinematics of the robotic arm or camera calibration, the proposed hybrid Jacobian controller can track a moving object using visual feedback and joint-space velocity feedback. The proposed hybrid control method is a combination of the uncalibrated visual servoing and approximate Jacobian feedback control. First, the Jacobian matrix from joint-space to image-space is estimated by recursive least-squares (RLS) algorithm, and then the approximate Jacobian feedback controller is designed by using visual feedback and joint-space velocity feedback. The performances of the proposed control methods are illustrated by computer simulations.     

关于一类不可微规划问题的对偶性

作者构造了一类不可微规划问题的一阶和二阶对偶模型,其目标函数含有紧凸集的支撑函数项.利用Fritz John最优性必要条件,在适当条件下建立了这两类一阶和二阶对偶模型的弱和逆对偶性定理.     

FEM modelling of single-core sandwich and 2-core multilayer beams containing foam aluminum core and metallic face sheets under monolithic bending

This present paper dealt with bending deformation and failure behavior of sandwich and multilayer beams composed of aluminum foam core and metallic face sheets by finite element method(FEM) and four-point bending test.Results revealed that collapse of the multilayer beams is dominated by two basic modes:indentation(ID) and core shear(CS).ID is dominated by the maximum compressive strain and CS by the maximum shear strain.The failure of the sandwich beams depends on if the face sheets show ID mode in the ...     

一维伊辛模型中的强关联

作者利用格林函数方法较严格地讨论了一维伊辛模型中任意两格点之间的自旋关联,并通过对比昂萨格的二维正方伊辛模型的结果表明,有限温度下一维伊辛模型尽管不存在通常的铁磁到顺磁的自发相变,但是存在零温附近的强自旋关联,从而可加深对一维伊辛模型的认识．     

A hybrid Jacobian control for uncalibrated robot visual servoing

Visualservocontrolhasbeenanactiveareaofre searchformanyyears.Since1973,therehasbeen significantprogressonvisualservoingcontrol[1],and severalspecialissuesonvisualservoinghavebeen published[2,3].Therearetwobasicapproachestovi sualservocontrol[1]:Position BasedVisualServoing(PBVS)andImage BasedVisualServoing(IBVS).InPBVSsystem,theobject’s3Dposeisrecovered throughcomputervisionandtheerrorbetweenthe currentposeandthedesiredposeiscomputedinthe Cartesiantaskspace.Estimationof3Dmotionsfrom…