Modeling mechanical disturbances induced by high intensity magnetic fields on electric motors

This is the authors' abstract. We don't add key points for this paper.

The increasing use of robotic platforms in hazardous and magnetically complex environments, such as underground research facilities at CERN, demands a detailed understanding of how strong external magnetic fields affect electromechanical actuation. Quadruped robots equipped with electromagnetic (EM) motors are particularly vulnerable, as their actuators interact directly with ambient magnetic fluxes, generating additional mechanical forces and moments that can compromise stability, trajectory tracking and overall operational safety. This work presents a modeling framework for estimating the equivalent magnetic moment of an EM motor subjected to high-intensity magnetic fields. The proposed approach combines numerical simulation datasets with an analytical dipole-based formulation to derive a computationally efficient model capable of predicting magnetic-induced mechanical disturbances in real/time. The model accounts for the dependence of the magnetic moment on both the external field intensity and the motor’s orientation relative to the field lines, enabling the control system to anticipate disturbance torques and implement appropriate compensation strategies. The accuracy and reliability of the model were validated experimentally by rotating a Unitree GO-M8010-6 motor within controlled magnetic fields and comparing the measured torques with the model predictions. The results demonstrate close agreement in both trend and amplitude, confirming that the proposed formulation can provide the level of fidelity required for real-time control applications in magnetically harsh environments.