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Scale Factor Estimation for Quadrotor Monocular-Vision Positioning Algorithms.
Alejandro Gómez-Casasola1, Hugo Rodríguez-Cortés1
1Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Ciudad de Mexico 07360, Mexico.
This study presents a new method for unmanned aerial vehicle (UAV) navigation using sensor fusion. It accurately estimates velocity and corrects position scale factors for safer autonomous flight.
Area of Science:
- Robotics
- Control Systems
- Computer Vision
Background:
- Autonomous navigation for unmanned aerial vehicles (UAVs) requires accurate state estimation.
- Existing methods often rely on multiple sensors due to limitations of single-sensor systems.
- Monocular vision-based simultaneous localization and mapping (SLAM) presents challenges in determining accurate position scale factors.
Purpose of the Study:
- To develop a deterministic estimator for reconstructing the position scale factor in monocular SLAM for quadrotor UAVs.
- To design a deterministic observer for estimating quadrotor translational velocity using only onboard sensor data.
- To validate the proposed methods using inertial and visual measurements.
Main Methods:
- Implementation of a deterministic estimator and observer based on the immersion and invariance (I&I) method.
- Fusion of inertial measurement unit (IMU) and visual odometry data.
- Utilization of Lyapunov stability theory to prove convergence of estimation errors.
Main Results:
- The proposed estimator successfully reconstructs the unknown position scale factor for monocular SLAM.
- The observer accurately estimates the quadrotor's translational velocity.
- Numerical simulations confirm the asymptotic convergence of estimation errors to zero.
Conclusions:
- The developed deterministic approach enhances the accuracy of UAV state estimation.
- This method enables more reliable autonomous navigation for quadrotors using monocular vision and IMU data.
- The validated techniques contribute to the advancement of robust UAV navigation systems.
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