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An Omnidirectional Vision Sensor Based on a Spherical Mirror Catadioptric System.
Sandro Barone1, Marina Carulli2, Paolo Neri3
1Department of Civil and Industrial Engineering, University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy. s.barone@ing.unipi.it.
Sensors (Basel, Switzerland)
|February 1, 2018
Summary
This study presents an analytical solution for non-central catadioptric vision systems using spherical mirrors. It offers a closed-form solution for forward and backward projection, improving computer vision applications.
Area of Science:
- Computer Vision
- Optics
- Robotics
Background:
- Catadioptric sensors, combining mirrors and lenses, are crucial in computer vision.
- Their design involves hardware, projection modeling, and calibration.
- Omnidirectional sensors with spherical mirrors are a key application.
Purpose of the Study:
- To provide a complete description of omnidirectional catadioptric sensors with spherical mirrors.
- To present an analytical closed-form solution for projection modeling.
- To develop a robust calibration procedure.
Main Methods:
- Developed an analytical closed-form solution for forward and backward projection in non-central catadioptric systems.
- Modeled forward projection as a 4th order polynomial by intersecting a sphere and an ellipse.
- Formulated models in matrix format for efficient point cloud processing.
- Proposed a robust calibration method to determine mirror parameters.
Main Results:
- Achieved an analytical, closed-form solution for both forward and backward projection for spherical mirror catadioptric systems.
- The forward projection is accurately represented by a 4th order polynomial.
- Matrix format models enable fast handling of point cloud data.
- The calibration procedure successfully determined mirror radius and center.
Conclusions:
- The presented analytical solution simplifies projection modeling for non-central catadioptric systems.
- This work provides a computationally efficient and accurate method for catadioptric sensor applications.
- The robust calibration procedure enhances the practical usability of these sensors.
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