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Cross-Axis Coupling Effects in Single-Axis Nuclear Magnetic Resonance Gyroscopes
Zhiguo Wang1, Yi Zhang1, Xiang Zhan1
1College of Advanced Interdisciplinary Studies, and Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha 410073, China.
Sensors (Basel, Switzerland)
|February 5, 2020
Summary
Angular vibration causes significant errors in nuclear magnetic resonance gyroscopes (NMRGs) by inducing cross-axis coupling. This can disrupt the gyroscope's ability to measure rotation rates, impacting inertial navigation systems.
Area of Science:
- Physics
- Engineering
Background:
- Nuclear magnetic resonance gyroscopes (NMRGs) are susceptible to environmental vibrations.
- Vibrations in operational environments often include both linear and angular components.
Purpose of the Study:
- To analyze the influence of angular vibration on NMRGs.
- To investigate cross-axis coupling effects in NMRGs under vibration.
Main Methods:
- Studied cross-axis coupling effects induced by angular vibration.
- Utilized Bloch equations to describe the influence of equivalent magnetic fields.
- Performed numerical simulations to validate analytical findings.
Main Results:
- Angular vibration induces an equivalent magnetic field, affecting NMRG performance.
- Analytical approximations for frequency shift and amplitude were obtained and validated.
- Significant errors in NMRG measurements were observed due to angular vibration components.
Conclusions:
- Angular vibration is a critical factor causing errors in NMRGs.
- Spin oscillation frequency can lock to angular vibration frequency near the Larmor frequency, compromising rotation rate measurement.
- Cross-axis coupling must be considered in NMRG design and inertial navigation system development.
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