Design and Simulation Analysis of a Magnetic Fluid-Based Horizontal Inclinometer

Magnetic fluid, a novel functional material with unique properties, is gradually demonstrating its advantages in various fields, including sensors. Here, a novel magnetic fluid inclinometer was proposed, mainly consisting of magnetic fluid, a mass block containing (coating) a magnetic layer, and external permanent magnets. Within the nonuniform magnetic field generated by the permanent magnets, as the mass block approaches, it experiences increasing forces from the magnetic fluid. External tilt variations are reflected in the mass block’s displacement, detected through a circuit similar to a differential transformer, thereby outputting external tilt angles. The magnetic layer arranged on the mass block is a prominent feature of the structure. Theoretical analysis simplifies the mass block’s force based on magnetic field distribution and indicates linear output within a small range (approximately one-third of the movable range). Simulation tests reveal that the magnetic layer increases circuit output by about 15 times. The structure displays excellent response speed and repeatability, achieving an effective linear range exceeding 30°, an average sensitivity of approximately 5 mV/°, and stability within 0.1–0.2 s. Experimental validation confirms the magnetic layer’s efficacy, demonstrating a current range from 6° to 90° with an average sensitivity of 3 mV/°.