Magnetic Nanoparticle-Based Gyroscopic Sensor: A Review

A gyroscopic orientation sensor is proposed using magnetic nanoparticles and electric current. Nanoparticles are spun in alternating magnetic fields. External forces imposed on the changing gyroscopic orientation of the nanoparticles cause a change in the strength of the magnetic field. The sensory effect of the magnetic strength is predicted using theoretical models for fluid friction, susceptibility, and local nanoparticle interactions. Fluid inertia and coupling between particles are negligible compared with the imposed field and are neglected to simplify the model. The configuration leads to an orientation sensor for detecting the change in orientation of nanoparticles in an alternating magnetic field.