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An Indoor Visual Positioning Method with 3D Coordinates Using Built-In Smartphone Sensors Based on Epipolar Geometry.
Ping Zheng1, Danyang Qin1,2, Jianan Bai1
1Department of Electronic and Communication Engineering, Heilongjiang University, Harbin 150080, China.
This study introduces a new indoor visual positioning method using smartphone sensors and epipolar geometry. It achieves accurate 3D coordinates, with 90% of errors below 0.58m, enabling reliable user localization.
Area of Science:
- Computer Vision
- Robotics
- Geomatics
Background:
- Traditional visual positioning methods struggle with mixed errors, leading to inaccurate direction vector convergence.
- Existing techniques often map 3D vectors to 2D planes, resulting in positioning errors, including points at infinity.
Purpose of the Study:
- To propose an improved indoor visual positioning method for accurate 3D coordinate determination.
- To overcome limitations of existing methods by integrating smartphone sensor data with visual computing.
Main Methods:
- The proposed method transforms the positioning problem into calculating the distance from a point to multiple lines in space.
- It fuses accelerometer and magnetometer data with visual information for enhanced coordinate accuracy.
- Epipolar geometry principles are utilized for geometric relation construction.
Main Results:
- The method demonstrates stable localization performance across various poses, even with limited image retrieval results.
- Experimental results show 90% of positioning errors are below 0.58 meters.
- The average positioning error is less than 0.3 meters, meeting practical application requirements.
Conclusions:
- The developed indoor visual positioning system offers a low-cost, accurate, and robust solution for user localization.
- Integration of inertial sensors significantly improves the reliability and accuracy of visual positioning.
- The method provides a practical alternative for applications requiring precise indoor positioning.
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