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arXiv · 2108.07936

Calibration Method of the Monocular Omnidirectional Stereo Camera

Ryota Kawamata·Keiichi Betsui·Kazuyoshi Yamazaki·Rei Sakakibara·Takeshi Shimano
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Abstract

Compact and low-cost devices are needed for autonomous driving to image and measure distances to objects 360-degree around. We have been developing an omnidirectional stereo camera exploiting two hyperbolic mirrors and a single set of a lens and sensor, which makes this camera compact and cost efficient. We establish a new calibration method for this camera considering higher-order radial distortion, detailed tangential distortion, an image sensor tilt, and a lens-mirror offset. Our method reduces the calibration error by 6.0 and 4.3 times for the upper- and lower-view images, respectively. The random error of the distance measurement is 4.9% and the systematic error is 5.7% up to objects 14 meters apart, which is improved almost nine times compared to the conventional method. The remaining distance errors is due to a degraded optical resolution of the prototype, which we plan to make further improvements as future work.

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Ryota Kawamata, Keiichi Betsui, Kazuyoshi Yamazaki, Rei Sakakibara, Takeshi Shimano. 2021-08-18. Calibration Method of the Monocular Omnidirectional Stereo Camera. https://arxiv.org/abs/2108.07936

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