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Published on: February 23, 2024
Synthetic velocity measurement algorithm of monocular vision based on square-root cubature Kalman filter
Jiaqi Wei1, Jun Liu1, Jun Tang1
1Key Laboratory of Instrumentation Science and Dynamic Measurement, Ministry of Education, School of Instrument and Electronics, North University of China, Taiyuan 030051, People's Republic of China.
This study introduces a new vision-based velocity measurement system for drones. It improves accuracy in varying light conditions by combining Lucas-Kanade optical flow and ORB algorithms with a square-root cubature Kalman filter.
Area of Science:
- Computer Vision
- Robotics
- Navigation Systems
Background:
- Vision-based velocity measurement is crucial for Unmanned Aerial Vehicle (UAV) navigation.
- Traditional Lucas-Kanade (LK) optical flow (OF) algorithms struggle with accuracy and adaptability under uneven illumination.
- Existing methods lack robustness in dynamic lighting environments.
Purpose of the Study:
- To develop a robust monocular vision integrated velocity measurement system for UAVs.
- To enhance the accuracy and adaptability of velocity estimation under challenging illumination conditions.
- To overcome the limitations of traditional optical flow algorithms in variable lighting.
Main Methods:
- Integration of the Lucas-Kanade (LK) optical flow algorithm with an optimized oriented FAST and rotated BRIEF (ORB) feature descriptor.
- Utilization of a square-root cubature Kalman filter (SRCKF) for sensor fusion.
- Processing visual information from a monocular camera for velocity computation.
Main Results:
- The proposed system effectively fuses LK OF and optimized ORB information.
- Improved velocity measurement accuracy was achieved in environments with variable illumination.
- The system demonstrated reduced sensitivity to illumination intensity variations compared to traditional LK OF.
Conclusions:
- The monocular vision integrated velocity measurement system based on SRCKF offers accurate velocity estimation for UAVs.
- The combined approach enhances robustness and adaptability in diverse lighting conditions.
- The method provides a reliable solution for UAV navigation in challenging visual environments.
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