Method and system for resolving hemisphere ambiguity using a position vector

A system comprising:

• a hand-held controller comprising a magnetic field transmitter configured to emit one or more magnetic fields;
• a headset comprising one or more magnetic field sensors configured to detect the one or more magnetic fields;
• a processor coupled to the headset configured to perform operations including:
• determining a first position and a first orientation of the hand-held controller within a first hemisphere with respect to the headset based on the one or more magnetic fields;
• determining a second position and a second orientation of the hand-held controller within a second hemisphere with respect to the headset based on the one or more magnetic fields, wherein the second hemisphere is diametrically opposite the first hemisphere with respect to the headset;
• determining a normal vector with respect to the headset, and a position vector identifying a position of the hand-held controller with respect to the headset in the first hemisphere;
• calculating a dot-product of the normal vector and the position vector;
• determining that the first position and the first orientation of the hand-held controller is accurate when a result of the dot-product is positive;
• and
• determining that the second position and the second orientation of the hand-held controller is accurate when the result of the dot-product is negative.

A computer-program product embodied in a non-transitory computer-readable medium, the computer-readable medium having stored thereon a sequence of instructions which, when executed by a processor, causes the processor to execute a method for resolving hemisphere ambiguity at a system comprising one or more sensors comprising:

• emitting, at a hand-held controller of the system, one or more magnetic fields;
• detecting, by one or more sensors positioned within a headset of the system, the one or more magnetic fields;
• determining a first position and a first orientation of the hand-held controller within a first hemisphere with respect to the headset based on the one or more magnetic fields;
• determining a second position and a second orientation of the hand-held controller within a second hemisphere with respect to the headset based on the one or more magnetic fields, wherein the second hemisphere is diametrically opposite the first hemisphere with respect to the headset;
• determining a normal vector with respect to the headset, and a position vector identifying a position of the hand-held controller with respect to the headset in the first hemisphere;
• calculating a dot-product of the normal vector and the position vector;
• determining that the first position and the first orientation of the hand-held controller is accurate when a result of the dot-product is positive;
• and
• determining that the second position and the second orientation of the hand-held controller is accurate when the result of the dot-product is negative.