Tri-band Torque Sensor with Redundant Magnetic Field Sensors

The magnetised region is segmented into multiple magnetic tracks (first, second, and third magnetic tracks) with opposing magnetisations. Each track is sensed by dedicated sensor coils, allowing independent measurement of magnetic field changes in each track. This segmentation enables differentiation between torque-induced changes (affecting all tracks equally) and environmental interference (affecting tracks differently), thereby improving measurement precision without excessive complexity.

Different regions of the magnetised component are assigned different magnetisation directions (first magnetic track: +, second magnetic track: -, third magnetic track: +). This local quality variation creates a pattern where environmental magnetic fields affect different tracks differently, while torque produces uniform changes. The sensor system exploits this local quality differentiation to distinguish between product-related and environmental magnetic influences.

The multiple magnetic tracks serve multiple functions simultaneously: they measure torque magnitude, detect environmental magnetic interference, and provide redundancy for fault detection. The sensor system evaluates relationships between track signals to distinguish torque from environmental effects, making the redundant sensor configuration useful for multiple measurement purposes rather than simply repeating the same measurement.

The system continuously monitors the relationships between signals from different magnetic tracks and uses this feedback to distinguish between torque-induced changes and environmental interference. By evaluating the pattern of changes across tracks, the system can identify when environmental factors are present and compensate or reject those measurements, improving reliability through active feedback-based discrimination.