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arXiv · 2610.04785

Lollypop: Camera-to-Motion-Capture Calibration Verification with a Reference Target

Tianyi Liu·Kevin Harris·Mihika Dave·Kun He
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Abstract

Camera-to-motion-capture (mocap) calibration is essential for using mocap as ground truth in robotics, AR/VR, and other computer vision tasks. However, the calibration can drift after deployment, while calibration residuals and visual inspection provide limited independent verification. We present Lollypop, a fiducial-mocap reference target for independent calibration verification. The target couples an ArUco fiducial with a mocap marker constellation so the visual center and tracked centroid represent the same physical point. Given a candidate calibration, verification projects the mocap point into the image and measures its disagreement with the detected fiducial center. Experiments show sub-pixel nominal error, sensitivity to controlled extrinsic perturbations, and increasing error during an illustrative mixed-handling sequence.

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Tianyi Liu, Kevin Harris, Mihika Dave, Kun He. 2026-10-03. Lollypop: Camera-to-Motion-Capture Calibration Verification with a Reference Target. https://arxiv.org/abs/2610.04785

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