Precise Target Geo-Location of Long-Range Oblique Reconnaissance System for UAVs

Area of Science:

• Aerospace Engineering
• Geospatial Information Science
• Robotics

Background:

• High-precision, real-time, long-range target geo-location is critical for Unmanned Aerial Vehicle (UAV) reconnaissance and strike missions.
• Traditional geo-location techniques face limitations due to GPS/INS accuracy, target elevation, and range-finding instrumentation, especially for long-range operations (LRORS).
• Digital Elevation Models (DEM) and geographic reference data are often unsuitable for long-range UAV applications.

Purpose of the Study:

• To develop a novel geo-location method for UAVs that overcomes the limitations of traditional approaches.
• To achieve high-precision, real-time target geo-location independent of GPS/INS accuracy, target elevation, and range-finding limitations.
• To enhance the accuracy and robustness of target geo-location for long-range UAV missions.

Main Methods:

• A multi-step approach involving initial rough geo-location calculation using traditional methods.
• Re-imaging the target based on the rough geo-location to identify re-projection errors caused by GPS/INS and elevation inaccuracies.
• Employing a weighted filtering algorithm to process re-projection errors and iteratively refine the target geo-location until convergence.

Main Results:

• The proposed method demonstrated significant improvements in geo-location accuracy, achieving 38.8 times higher accuracy than traditional methods.
• Compared to DEM methods, the novel approach yielded a 22.5 times improvement in geo-location accuracy.
• Simulations and flight experiments validated the method's efficiency, robustness, and ease of implementation.

Conclusions:

• The developed geo-location method effectively addresses the limitations of existing techniques for long-range UAV applications.
• The iterative refinement process using re-projection error significantly enhances target geo-location precision.
• The method offers a robust and easily implementable solution for high-precision target geo-location in UAV reconnaissance.