The accurate estimation of the end-effector’s pose in large operating spaces is the key for the mobile manipulator to realize efficient manufacturing of large and complex components.We propose a novel pose tracking m...The accurate estimation of the end-effector’s pose in large operating spaces is the key for the mobile manipulator to realize efficient manufacturing of large and complex components.We propose a novel pose tracking method in large-range using visual fiducial markers,and further propose the layout optimization method for the encoded fiducial markers.A metric named orientational dilution of precision(ODOP)is proposed to evaluate the magnification of the pose estimation error compared with the measurement error of the coded fiducial markers.The distribution pattern of the coded markers is analyzed based on ODOP,and the square-shaped layout is determined to be a satisfactory distribution pattern for the minimum positioning unit of markers,and the side length of the square-shaped layout is further selected.The simulations and experiments prove the effectiveness of the ODOP index.Finally,the square-shaped layout and the designed distribution density for positioning coded markers are adopted to realize the high-precision measurement of large components by the mobile manipulator.展开更多
The Inner Formation Flying System （IFFS） consisting of an freely flying in the shield cavity can construct a pure gravity outer satellite and an inner satellite which is a sphere proof mass orbit to precisely detect...The Inner Formation Flying System （IFFS） consisting of an freely flying in the shield cavity can construct a pure gravity outer satellite and an inner satellite which is a sphere proof mass orbit to precisely detect the earth gravity field. The residual gas in the cavity is a significant disturbance source due to the temperature inhomogeneity and relative motion of the inner satellite. The expressions of the disturbance forces were derived based on the property of rarefied gas, including the radiometer effect and the damping force. According to the current design of IFFS, heat transfer analysis of the cavity and the inner satellite was carried out, and the surface temperature distribution of the cavity and the inner satellite was given. The relative motion of the inner satellite was obtained from the formation control simulation of IFFS. Then the residual gas disturbance was calculated. The disturbance acceleration acting on the inner satellite due to the radiometer effect was on the order of 10^-11 m s^-2 and the damping acceleration was on the order of 10^-15 m s^-2.展开更多
基金supported in part by the National Key Research and Development Program of China(Grant No.2017YFB1301504)the National Natural Science Foundation of China(Grant Nos.91748204,91948301 and 51905183)the China Postdoctoral Science Foundation(Grant No.2018M642820).
文摘The accurate estimation of the end-effector’s pose in large operating spaces is the key for the mobile manipulator to realize efficient manufacturing of large and complex components.We propose a novel pose tracking method in large-range using visual fiducial markers,and further propose the layout optimization method for the encoded fiducial markers.A metric named orientational dilution of precision(ODOP)is proposed to evaluate the magnification of the pose estimation error compared with the measurement error of the coded fiducial markers.The distribution pattern of the coded markers is analyzed based on ODOP,and the square-shaped layout is determined to be a satisfactory distribution pattern for the minimum positioning unit of markers,and the side length of the square-shaped layout is further selected.The simulations and experiments prove the effectiveness of the ODOP index.Finally,the square-shaped layout and the designed distribution density for positioning coded markers are adopted to realize the high-precision measurement of large components by the mobile manipulator.
基金supported by the National Natural Science Foundation of China (Grant No. 11002076)
文摘The Inner Formation Flying System （IFFS） consisting of an freely flying in the shield cavity can construct a pure gravity outer satellite and an inner satellite which is a sphere proof mass orbit to precisely detect the earth gravity field. The residual gas in the cavity is a significant disturbance source due to the temperature inhomogeneity and relative motion of the inner satellite. The expressions of the disturbance forces were derived based on the property of rarefied gas, including the radiometer effect and the damping force. According to the current design of IFFS, heat transfer analysis of the cavity and the inner satellite was carried out, and the surface temperature distribution of the cavity and the inner satellite was given. The relative motion of the inner satellite was obtained from the formation control simulation of IFFS. Then the residual gas disturbance was calculated. The disturbance acceleration acting on the inner satellite due to the radiometer effect was on the order of 10^-11 m s^-2 and the damping acceleration was on the order of 10^-15 m s^-2.
