2017 年 83 巻 12 号 p. 1201-1208
This paper proposes a novel method to improve the robustness for scale-reconstructible structure from motion (SfM) using refraction. SfM is a three-dimensional (3D) measurement method using a single moving camera. The conventional SfM can simultaneously estimate the 3D positions of objects and camera poses. However, the real-world scales of objects cannot be determined. To solve this problem, a SfM using refraction was proposed. In the SfM using refraction, it was verified that the object shapes could be reconstructed with their real-world scales using just two images captured through a refractive plate. However, the SfM using refraction is greatly influenced by measurement errors, leading to reconstruction failure. The purpose of this paper is to improve the robustness for scale-reconstructible SfM using refraction. To that end, bundle adjustment considering the influence of refraction is proposed. We propose approaches to selection of initial values for bundle adjustment and evaluation function of the optimization. In simulations, it was verified that the 3D reconstruction was successful by applying the proposed method even if the measurement errors were large. The reconstruction was also successful in reconstructing the scale of the object in the real experiment.