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Absolute IOP/EOP Estimation Models without Initial Information of Various Smart City Sensors
Namhoon Kim1, Sangho Baek1, Gihong Kim2
1Department of Civil Engineering and Environmental Sciences, Korea Military Academy, 574 Hwarang-ro, Nowon-gu, Seoul 01805, Republic of Korea.
This study estimates optical sensor position and orientation using mobile mapping point clouds. The perspective projection model provided the most accurate results for smart city camera calibration.
Area of Science:
- Geomatics Engineering
- Computer Vision
- Smart City Technology
Background:
- Smart cities extensively deploy optical sensors like CCTV and UAVs.
- Crucial sensor data (3D position, orientation, principal distance) is often missing.
- This limits the utility of collected visual data for precise mapping and analysis.
Purpose of the Study:
- To develop and evaluate methods for estimating optical sensor parameters without prior information.
- To determine the optimal model for calculating sensor position, orientation, and principal distance.
- To address the challenge of missing metadata in smart city optical sensing.
Main Methods:
- Utilized structured mobile mapping system point clouds for sensor calibration.
- Applied two Direct Linear Transformation (DLT) models and a perspective projection model.
- Calculated principal distance and estimated sensor position and orientation.
- Tested the stability and accuracy of estimation methods with real-world sensor data.
Main Results:
- The perspective projection model yielded the most accurate estimations for camera position and orientation.
- The original DLT model showed significant orientation estimation errors, possibly due to parameter correlation.
- Achieved position and orientation errors of 0.80 m and 2.55° respectively with the perspective projection model.
- Fixed-wing UAV application faced challenges due to ground control point placement issues.
Conclusions:
- The perspective projection model is superior for estimating optical sensor pose and principal distance in smart city contexts.
- Mobile mapping point clouds offer a viable solution for calibrating uncalibrated optical sensors.
- Further research is needed to overcome challenges in specific platforms like fixed-wing UAVs and ensure robust ground control.
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