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arXiv · 2610.17873

Information-based Unified Design Framework for NMR Magnetic Tracking System

Seçkin Eren Yetim·Mehmet Efe Tiryaki
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Abstract

Nuclear magnetic resonance (NMR) magnetic tracking offers a promising alternative to magnetic resonance imaging (MRI)-based localization for medical robotic guidance. However, scalar field measurements and field-aligned marker moments constrain position and orientation tracking, requiring careful configuration design. We present a unified information-based framework that uses local covariance analysis to evaluate receiver geometry, marker separation, and external source configuration in on/off-board NMR tracking. Numerical evaluation shows that planar-array precision depends jointly on receiver count and geometry, with triangular lattice arrays achieving the lowest best-case position uncertainty among the evaluated layouts for 9--20 receivers. Two spatially separated, field-aligned markers enable device-axis tracking, with predicted angular uncertainty below $2^\circ$ at the evaluated workspace center for suitable marker separations. We further establish point-dipole source--receiver duality, unifying the analysis of on/off-board NMR tracking. These

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Seçkin Eren Yetim, Mehmet Efe Tiryaki. 2026-10-13. Information-based Unified Design Framework for NMR Magnetic Tracking System. https://arxiv.org/abs/2610.17873

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