How to tackle the challenge
Digital sensors integrate a lot of the signal conditioning, compensation and calibration making the implementation of such a concept relatively simple.
Current measurement solutions are available, integrated into low-profile packaging that can handle up to +/- 50A of AC or DC signal measurement. The high-precision TLI4970 is such a device, utilizing Hall sensor technology in a measurement principle that galvanically isolates the primary conductor from the secondary interface.
Being a coreless measurement solution, the overall solution is very compact, and more accurate than open-loop systems using a magnetic core. The primary conductor (current rail) is integrated into the package, leaving no need for external calibration. Its output is also highly linear, without hysteresis, and effective suppression of stray fields is achieved using a differential measurement principle.
For the area of robotic joint motion detection, magnetic field measurement solutions can leverage the properties of Giant Magneto Resistance (GMR) sensors. Such devices provide angular measurement of commutated motors by monitoring magnetic fields in two planes. This sine and cosine output is passed to a digital signal processing block that uses the trigonometric ARCTAN2 function to deliver the true 360° angle of, for example, a motor rotor.