On-orbit calibration method and system for space manipulator based on hand-eye camera

Abstract

The invention relates to an on-orbit calibration method and system for a space manipulator based on a hand-eye camera. The on-orbit calibration method comprises the steps of (1) performing imaging ona target by using the hand-eye camera installed at the tail end of the space manipulator under multiple groups of different configurations; (2) recording angle measurement values of joints of the space manipulator and position and pose data, which is measured by the hand-eye camera, of the tail end of the space manipulator under each group of configurations; (3) substituting the joint angle data and the tail end position and pose data of the space manipulator under different configurations into a space manipulator forward kinematics equation, and building a nonlinear equation set related withstructural parameters of the space manipulator; and (4) solving the built nonlinear equation set by adopting a numerical iterative algorithm to obtain structural parameters of the space manipulator. The method can be applied to performing on-orbit calibration on the structural parameters of the space manipulator after a spacecraft is launched into the orbit, so that the control accuracy of the space manipulator is effectively improved.

Description

technical field [0001] The invention relates to an on-orbit calibration method and system for a space manipulator based on a hand-eye camera, belonging to the technical field of space robots. Background technique [0002] For the space manipulator, especially the dexterous manipulator, in order to realize the accurate operation of the end tool on the target, the space manipulator is often required to have high control accuracy. The control accuracy of the end of the manipulator is directly related to the measurement accuracy of the structural parameters of the manipulator itself. Under ground conditions, with the help of accurate ground measurement devices, it is relatively easy to achieve precise measurement of the structural parameters of the manipulator. However, the space manipulator will bear huge vibration and shock during the launch process of the aircraft. At the same time, the space environment of the manipulator in orbit and the ground environment are quite differ...

AI Technical Summary

Problems solved by technology

[0006] The shortcomings of the technical solutions of the above documents are mainly reflected in: (1) the method of using the correction matrix is ​​only applicable to the space manipulator working in a certain configuration, not applicable to all configurations; (2) the existing The methods all adopt the linearization method, and the calculation process of the linearization method is relatively complicated. For each calibration test case, the nonlinear model needs to be linearized, and then the data is processed; The process of linearizing the nonlinear model of the manipulator is actually an approximation process, so it will inevitably lead to a reduction in calibration accuracy

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