Head-tracking system and method

A head-tracking system, comprising:

• a georeferenced head tracker (GHT) configured to be associated with a head of a user and to provide georeferenced head position data, the GHT having a current drift error;
• an optical head-tracker (OHT) configured to be associated with the head of the user and to provide optical platform-referenced head position data;
• a magnetic head-tracker (MHT) configured to be associated with the head of the user and to provide magnetic platform-referenced head position data;
• a controller coupled with the GHT, the OHT, and the MHT, and configured to be coupled with at least one avionic system configured to provide georeferenced aircraft position data, the controller including at least one processor coupled with a non-transitory processor-readable medium storing processor-executable code for causing the at least one processor to:
• access the georeferenced head position data and compare the current drift error of the GHT with a predetermined drift error threshold;
• in response to the current drift error of the GHT being below the predetermined drift error threshold, transmit at least one signal indicative of the georeferenced head position data being a current georeferenced head position data;
• and
• in response to the current drift error of the GHT exceeding the predetermined drift error threshold, generate update data based on the georeferenced aircraft position data and at least one of:
• the optical platform-referenced head position data and the magnetic platform-referenced position data;
• and update the GHT with the update data at a known instant in time wherein the non-transitory processor-readable medium further stores processor-executable code for causing the at least one processor to:
• access a magnetic calibration map indicative of a magnetic environment in a region surrounding the head of the user;
• and calibrate the MHT based on the magnetic calibration map;
• wherein the non-transitory processor-readable medium further stores processor-executable code for causing the at least one processor to at least one of:
• dynamically update the magnetic calibration map and periodically update the magnetic calibration map.

A method of providing georeferenced head position data, comprising:

• accessing, by at least one processor executing processor-executable code stored in a non-transitory processor-readable medium, georeferenced head position data from a georeferenced head tracker (GHT) configured to be associated with a head of a user onboard a moving aircraft, the GHT having a current drift error;
• comparing, by the at least one processor, the current drift error of the GHT with a predetermined drift error threshold;
• in response to the current drift error of the GHT being below the predetermined drift error threshold, transmitting, by the at least one processor, at least one signal indicative of the georeferenced head position data being a current georeferenced head position data;
• in response to the current drift error of the GHT exceeding the predetermined drift error threshold:
• accessing, by the at least one processor, platform-referenced head position data from a platform-referenced head-tracker (PRHT) configured to be associated with the head of the user and georeferenced aircraft position data from at least one avionic system;
• generating, by the at least one processor, update data based on the platform-referenced head position data and the georeferenced aircraft position data;
• and
• updating, by the at least one processor, of the GHT with the update data at a known instant in time
• wherein accessing, by the at least one processor, platform-referenced head position data further comprises accessing magnetic platform-referenced head position data from a magnetic head tracker (MHT) configured to be associated with the head of the user;
• accessing, by the at least one processor, a magnetic calibration map indicative of a magnetic environment in a region surrounding the head of the user;
• and
• calibrating, by the at least one processor, the MHT based on the magnetic calibration map.