Improvement of the Pointing Accuracy of Shipborne Optical Measuring Equipment Based on a Subdivision Iteration Algorithm

Abstract

When performing measurement and control tasks at sea, the optical measuring equipment on an aerospace survey ship must demonstrate a high pointing accuracy. Ideally, a fixed sequence of “yaw–pitch–roll” is used to perform the coordinate transformation from the Earth reference system to the deck coordinate system, introducing a coordinate transformation error. This study proposes a parametric model based on the subdivision iterative algorithm to correct the errors of the coordinate–transformation sequence of the ship’s attitude and systematic errors caused by the coupling of several error sources to improve the pointing accuracy of the space–measurement equipment on a ship. Star-tracking experiments verify the validity of the model. Compared with the existing models, the proposed pointing–error model reduces the corrected residual from $42^{\prime \prime }$ to $18.4^{\prime \prime }$ and the open-loop pointing error from $11.5^{\prime \prime }$ to $8.1^{\prime \prime }$ . The results show that the application of the proposed model helped improve the pointing accuracy of the optical measuring equipment after correction. These findings could prove significant for similar studies on goniometric precision and data processing accuracy.

Keywords

• Coordinate–transformation error
• optical measuring equipment
• pointing–error analysis
• star–tracking experiments