Multi-satellite formation distributed relative navigation method based on information fusion

Abstract

The invention discloses a multi-satellite formation distributed relative navigation method based on information fusion. The method comprises the following steps: each slave satellite constructs two groups of different measurement configurations through communication negotiation or neighbor; establishing a filtering relative motion state equation and a distance and angle measurement equation; performing state estimation on the local measurement configuration 1 by using CKF filtering; performing time updating on the local measurement configuration 2 by using the CKF, and replacing a corresponding state prediction value with a state estimation result of the local filter 1 to perform measurement updating; information fusion is carried out on the main filter; and if the formation configuration changes, reconstructing the measurement configuration, otherwise, directly entering the Kalman filtering state again by the system. According to the method, a distributed filtering structure is introduced, a traditional main satellite estimation link is decomposed into multi-satellite joint calculation, the filtering calculation amount and the single-point fault risk are reduced, meanwhile, the precision is guaranteed through information fusion, and the relative navigation system has accuracy, robustness and expansibility.

Description

technical field [0001] The invention relates to the technical field of formation satellite relative navigation, in particular to a multi-satellite formation distributed relative navigation method based on information fusion. Background technique [0002] Satellite formation flight refers to the cooperation of multiple small satellites to replace large satellites to complete complex tasks. Formation satellites form periodic relative motion orbits, and through mutual communication, they cooperate to complete functions such as detection, tracking, measurement and remote sensing. In view of the advantages of satellite formation in terms of cost, coverage and function, this technology is regarded as the frontier of aerospace technology in the 21st century and has broad development and application prospects. The relative navigation of formation satellites refers to the process of determining the relative position and relative velocity between satellites. Satellite formation flig...

AI Technical Summary

Problems solved by technology

[0004] Although CKF can realize the estimation of the relative state of formation satellites, the increase in the number of satellites will lead to a linear increase in the dimension of CKF state estimation, which poses a great challenge to the computing power of the satellite and the inter-satellite link communication.

Also, relative navigation systems are not robust

When the main star fails, the entire navigation function will be paralyzed; the withdrawal and joining of the slave star also requires the main star to correct the filter in real time, and the real-time performance of the navigation task is difficult to guarantee

Images