1. A method for adjusting an estimated spatial position and orientation of an object using a sensor, the method comprising: using a processing module, adjusting the estimated spatial position and orientation of the object by detecting and removing bias in local magnetic declination and inclination values obtained from a reference earth magnetic model, wherein the bias in the local magnetic declination and inclination values is calculated based on one or more measurements of absolute orientation of the sensor derived from data transmitted by the sensor to the processing module; and updating the adjusted estimated spatial position and orientation on a display device.