Increased precision position sensors

A position sensor for sensing the position of an object having an associated magnetic field comprising:

• a first magnetic field sensing device at a first position that outputs a first signal related to the magnetic field at the first position;
• a second magnetic field sensing device at a second position that outputs a second signal related to the magnetic field at the second position;
• a processor to derive from the first signal and the second signal the most likely position of the position sensor relative to the object,
• wherein the processor comprises:
• a first calibrator to calibrate the first magnetic field sensing device, thereby deriving a first measured magnetic field;
• a second calibrator to calibrate the second magnetic field sensing device, thereby deriving a second measured magnetic field;
• a mathematical model to determine a predicted magnetic field at a given position relative to the object;
• an estimator algorithm to compare the predicted magnetic field with the first and second measured magnetic fields, thereby calculating the most likely position of the position sensor relative to the object.