A system and method for tracking the position and orientation of a movable medical imaging device using a first and second sensor disposed on the device. The second sensor is of a different type than the first sensor and measures a P/O parameter different from that of the first sensor. The system and method also include techniques for recalibrating sensors using measurements from other sensors and improving the measurements made by some sensors using measurements from other sensors. The system and method also include measuring the position of a medical implement relative to a movable medical imaging device by providing a first and second subsystem on the medical implement and a third and fourth subsystem on the movable medical imaging device. The first subsystem has a sensor of a first type and the second subsystem has a sensor of a second type different from the sensor of the first type. The third subsystem has a sensor of a third type and the fourth subsystem has a sensor of a fourth type different from the third type.