On the accuracy of solution of kinematic equations. I. Equation of errors.

Error equations are derived for the solution of kinematic equations by the quaternion method. It is shown that all the error sources can be reduced to an equivalent error of the primary information. Examples of determining solutions of the kinematic equations and their errors are considered, with particular attention given to the use of angular velocity as the primary information (a case typical for spacecraft attitude measurements). The present study is also pertinent to the formulation of kinematic equations for strapdown inertial navigation.