Relative Position Calculation of Distributed Spacecrafts Based on Improved Kalman Filter

Comparing to point estimation,kalman filter is useful to improve positioning precision of relative position of distributed spacecrafts.But divergence problem often exists in traditional kalman filter and this can reduce filtering-precision.One improved kalman filter was designed after studying the traditional methods.It was improved mainly from the aspects of design of initial values and adaptive adjustment.According to the state and measuring equation about relative position of distributed spacecrafts,this improved filter was used to calculate the position.The results of simulation revealed that the filtering-precision of three-axis all reached centimeter level.Compared to traditional kalman filter,this filter overcome the divergence and advanced the filtering precision efficiently.