On-orbit calibration approach for optical navigation camera in deep space exploration.

Area of Science:

• Spacecraft Navigation
• Optical Engineering
• Robotics

Background:

• Accurate optical navigation is crucial for autonomous spacecraft missions.
• The line-of-sight (LOS) of navigation cameras directly impacts navigation precision.
• On-orbit calibration is essential to maintain camera accuracy during missions.

Purpose of the Study:

• To develop and validate an on-orbit calibration approach for spacecraft-borne navigation cameras.
• To enhance the accuracy of the camera's line-of-sight (LOS) in the inertial frame.
• To improve the efficiency and robustness of on-orbit parameter estimation.

Main Methods:

• Stepwise on-orbit calibration of the navigation camera.
• Estimation of external and internal camera parameters in a generalized camera frame.
• Batch and sequential estimation methods to conserve computing power.
• A strategy for rejecting misidentified reference stars during estimation.

Main Results:

• Achieved high accuracy for the camera's line-of-sight (LOS) in the inertial frame, meeting autonomous navigation requirements.
• Demonstrated precise and robust performance of the calibration method through three experiments.
• Validated the effectiveness of the proposed batch and sequential estimation methods.

Conclusions:

• The developed on-orbit calibration approach ensures the accuracy needed for optical autonomous navigation.
• The method is precise, robust, and computationally efficient for real-time spacecraft operations.
• Successful validation confirms the approach's suitability for space missions.