Calibration method of magnetic field model and controller for electromagnetic positioning

A controller, comprising:

• a memory, configured to store a program code;
• a processor, coupled to the memory and loads the program code to execute:
• establishing a magnetic field through a magnetic field transmitter;
• obtaining measurement data through a magnetic field sensor, wherein the measurement data includes the amplitudes of induced voltage at multiple measurement positions in the magnetic field;
• and
• correcting a magnetic field model according to an error between the measurement data and simulation data, wherein the magnetic field model is used to generate the simulation data corresponding to the measurement locations, and the processor is further configured to:
• establishing at least one objective function through a nonlinear least squares method based on the error between the measurement data and the simulation data;
• and
• determining the modified magnetic field model based on at least one solution of the at least one objective function, wherein the at least one solution of the at least one objective function comprises a value of a scale parameter and a height compensation parameter, the scale parameter corresponds to amplitudes of induced voltage of the simulation data in the at least one objective function, and the height compensation parameter is used to modify a ground truth actual height in a z-axis direction;
• and
• performing spatial positioning through the modified magnetic field model to estimate a position corresponding to magnetic flux measured by the magnetic field sensor.