Study of second-order nonlinear interpolation filtering for satellite attitude determination

A second-order nonlinear filtering algorithm with good real-time performance is given based on the polynomial interpolation approximation.Using the algorithm the second-order nonlinear interpolation attitude estimator is developed for the typical stellar-inertial attitude determination system.The implementation of the new attitude estimation algorithm is significantly simpler.The computational burden of the new algorithm is comparable to that of the conventional extended Kalman attitude estimation algorithm.But the performance of the new algorithm is the same as that of the nonlinear attitude estimation algorithm based on second-order Taylor approximation.In addition,the singularity of the covariance matrix caused by the constraint on the attitude quaternion normalization is avoided in the second-order nonlinear interpolation attitude estimation algorithm.