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Design of a Smartphone Indoor Positioning Dynamic Ground Truth Reference System Using Robust Visual Encoded Targets
Xuan Liao1, Ruizhi Chen2, Ming Li3,4
1State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing, Wuhan University, Wuhan 430079, China. liaoxuan@whu.edu.cn.
Sensors (Basel, Switzerland)
|March 16, 2019
Summary
This study introduces a novel system for precise smartphone indoor positioning ground truth. It uses color visual scatter-encoded targets and machine vision for real-time accuracy evaluation.
Area of Science:
- Computer Vision
- Robotics
- Geomatics
Background:
- Real-time, dynamic, and precise measurement of smartphone indoor positioning ground truth is challenging.
- Existing methods often lack accuracy or real-time capabilities for dynamic evaluations.
Purpose of the Study:
- To develop a robust, high-precision, real-time ground truth reference system for smartphone indoor positioning.
- To enable accurate dynamic evaluation of various smartphone positioning technologies.
Main Methods:
- Designed novel high-precision color visual scatter-encoded patterns with robust recognition.
- Utilized a smartphone to capture image sequences for establishing an indoor coordinate system.
- Employed a high-efficiency algorithm to decode targets and obtain instantaneous smartphone camera pose.
Main Results:
- The designed scatter-encoded patterns are easily detectable, identifiable, and affordable.
- The system accurately and quickly determines the dynamic instantaneous pose of a smartphone camera.
- Established a high-precision and high-availability ground truth reference system.
Conclusions:
- The proposed system offers a fast, efficient, and low-cost method for evaluating smartphone indoor positioning accuracy.
- This technology enables accurate self-positioning of smartphones using artificial scatter feature visual positioning.
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