Revealing the potential of a new 3D Hall sensor in advanced inspection robotics

Abstract

This paper presents a novel CMOS magnetic field sensor designed for the simultaneous measurement of all three magnetic field components (Bx, By, and Bz) at a single location. The sensor incorporates three sets of mutually orthogonal horizontal and vertical Hall-effect elements, each equipped with dedicated biasing circuits and amplifiers. With a compact field-sensitive volume of only 100 x 100 x 10 μm³, the 3D sensor achieves exceptional spatial resolution. Leveraging CMOS technology ensures precise angular accuracy and orthogonality of the three measurement axes. Additionally, the sensor utilizes a spinning-current technique to effectively address challenges such as offset, low-frequency noise, and planar Hall effect. With a wide analog bandwidth spanning from DC to 300 kHz and an integrated temperature sensor, the sensor is versatile and applicable to a range of uses, including 3D positioning sensors, proximity sensors, current sensors, and magnetometry. To demonstrate its practical application, this paper explores the utilization of the 3D sensor for enhanced adhesion control in inspection robots. The innovative features of this CMOS magnetic field sensor make it a promising solution for diverse scientific and industrial applications.