Research And Design Of Autonomous Orbit Determination Algorithm For Deep Space Explorer

It is of great significance to study the self-locating orbit technique of deep-space detectors,which can reduce the trouble of relying on the ground station to monitor and control,and improve the ability of the detectors to deal with emergencies.Especially for our country this kind of monitoring and control resources shortage situation,its significance is even more obvious.In this paper,the Mars probe as the object of its independent measurement of orbit technology to study.This paper will do research cruise and Mars atmospheric entry in two ways: the use of rail determination method of image information based on the asteroid independent cruise phase,this method to design a standard track for flying,and then study the asteroid screening method to screen out the suitable asteroid observations,the sight vector information of asteroids and by introducing batch least squares algorithm based on Unscented transform(UBLS)estimation of detector position and speed;entry in the atmosphere,according to the characteristics of this stage are given a simplified dynamics model and equation of state can be used for program analysis,and then analyzed the traditional IMU measurement based on autonomous orbit determination algorithm and the existing problems,aiming at the existing problems,a combination of IMU and orbit determination scheme is proposed based on radio measurement,In this scheme,the acceleration of IMU measurement is taken as an external view measurement.At the same time,two additional distance observation measurements are added.At last,the UKF filtering algorithm is used to filter,and it is compared with the traditional method.The simulation results show that the asteroid screening criterion and the screening method are effective.The autonomous algorithm based on asteroid image information can improve the orbit accuracy when using the improved UBLS algorithm.The proposed autonomous measurement based on IMU and radio measurement program can significantly improve the progress of the determination of the track to meet the orbit requirements of the detector.