Real-Time Angular Motion Decoupling and Attitude Updating Method of Spinning Bodies Assisted by Satellite Navigation Data

Conventional attitude algorithms have been improved for many years, but they still have attitude updating errors due to the coupling in the complicated angular motion of spinning bodies. A real-time angular motion decoupling and attitude updating method assisted by satellite navigation data is proposed in this paper. A compositive model of angular motion for spinning bodies is built to understand and analyze the trait of angular velocity. A detailed process of angular motion decoupling is addressed with the help of satellite navigation data, including a backward decoupling process and a forward decoupling angular process, to estimate angular velocity to guarantee real-time ability. A real-time attitude updating algorithm is presented in detail for determining the real attitude of spinning bodies, and the updating process of coning attitude based on rotation vector is provided. Simulations are carried out to show the coupling effect of angular motion on the conventional attitude algorithm and verify the validity of the proposed method, and flight data are used to verify the availability of engineering application. Results show that the angular motion is decoupled and attitude accuracy is improved successfully.