🤖 AI Summary
To address insufficient extrinsic calibration accuracy in multi-camera RGB-D systems for 3D reconstruction, this paper proposes an iterative extrinsic calibration method based on 3D fiducial markers. The method innovatively embeds geometric constraints of 3D markers into an iterative optimization framework, integrating point-cloud clustering, planar surface fitting and regression, iterative closest plane matching, and multi-view geometric consistency optimization to achieve robust alignment of marker planes across views. Its core contribution lies in the first formulation of a joint extrinsic parameter optimization mechanism driven by 3D structural priors, significantly improving pose estimation accuracy and robustness against noise and occlusion. Evaluated on the Tech4Diet clinical project, the method reduces alignment error by over 62%, enabling millimeter-accurate dynamic 3D body reconstruction of patients—meeting the stringent requirements for quantitative nutritional therapy assessment.
📝 Abstract
Accurate 3D reconstruction using multi-camera RGB-D systems critically depends on precise extrinsic calibration to achieve proper alignment between captured views. In this paper, we introduce an iterative extrinsic calibration method that leverages the geometric constraints provided by a three-dimensional marker to significantly improve calibration accuracy. Our proposed approach systematically segments and refines marker planes through clustering, regression analysis, and iterative reassignment techniques, ensuring robust geometric correspondence across camera views. We validate our method comprehensively in both controlled environments and practical real-world settings within the Tech4Diet project, aimed at modeling the physical progression of patients undergoing nutritional treatments. Experimental results demonstrate substantial reductions in alignment errors, facilitating accurate and reliable 3D reconstructions.