LDM, 359: RAF Avro Vulcan Ground Position Indicator MK. 4 Part 1

This video presents the teardown of a vintage Ground Position Indicator which was used in Avro Vulcan aircrafts. If someone knows something about this device please let me know, particularly the purpose of the various controls on the front panel. 00:00 Intro 03:54 Teardown 05:16 Disk Ball integrator 07:33 Latitude and Longitude computations 13:44 Normal, Fix modes 15:16 Synchronous motor 16:14 Test with manual heading change 17:26 Longitudelatitude simplified electromechanical diagram Notes: At that time the goal of the third disc and ball integrator (on the bottom side) is unknown The goal of the motor linked to each output differential gear is unknown. I am not sure that they are used for wind correction (unlike in the PHI4A navigation computer) because the velocity of the shaft of these motors is not controlled. The Lat, Lon are permuted in the simplified electromechanical diagram Latitude, Longitude computation: