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arXiv · 2109.05928

Vision-based system identification and 3D keypoint discovery using dynamics constraints

Miguel Jaques·Martin Asenov·Michael Burke·Timothy Hospedales
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Abstract

This paper introduces V-SysId, a novel method that enables simultaneous keypoint discovery, 3D system identification, and extrinsic camera calibration from an unlabeled video taken from a static camera, using only the family of equations of motion of the object of interest as weak supervision. V-SysId takes keypoint trajectory proposals and alternates between maximum likelihood parameter estimation and extrinsic camera calibration, before applying a suitable selection criterion to identify the track of interest. This is then used to train a keypoint tracking model using supervised learning. Results on a range of settings (robotics, physics, physiology) highlight the utility of this approach.

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Miguel Jaques, Martin Asenov, Michael Burke, Timothy Hospedales. 2021-09-13. Vision-based system identification and 3D keypoint discovery using dynamics constraints. https://arxiv.org/abs/2109.05928

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