Method and system utilizing phased array beamforming for six degree of freedom tracking for an emitter in augmented reality systems
An electromagnetic tracking system includes a handheld controller including a first phased array element characterized by a first phase and a second phased array element characterized by a second phase different than the first phase. The first phased array element and the second phased array element are configured to generate a steerable electromagnetic beam characterized by an electromagnetic field pattern. The electromagnetic tracking system also includes a head mounted augmented reality display including an electromagnetic sensor configured to sense the electromagnetic field pattern.
1. An electromagnetic tracking system comprising:
a handheld controller including an electromagnetic emitter, the electromagnetic emitter including:
a first phased array element characterized by a first phase; and
a second phased array element characterized by a second phase different than the first phase;
wherein the first phased array element and the second phased array element are configured to generate a steerable electromagnetic beam characterized by an electromagnetic field pattern;
a head mounted augmented reality display including an electromagnetic sensor configured to sense the electromagnetic field pattern; and
one or more processors configured to:
determine a pose of the electromagnetic sensor;
control the first phase and the second phase to steer the electromagnetic beam to increase received power at the electromagnetic sensor; and
determine a pose of the handheld controller using the pose of the electromagnetic sensor and the electromagnetic field pattern sensed at the electromagnetic sensor.
2. The electromagnetic tracking system of claim 1 , wherein the one or more processors are further configured to:
digitally compute a position and orientation of the handheld controller based on the electromagnetic field pattern.
3. The electromagnetic tracking system of claim 1 , wherein at least one of the one or more processors is disposed in the handheld controller.
4. The electromagnetic tracking system of claim 1 , further comprising an auxiliary unit including the handheld controller.
5. The electromagnetic tracking system of claim 4 , wherein the auxiliary unit comprises a belt pack.
6. The electromagnetic tracking system of claim 1 , wherein the electromagnetic emitter further comprises a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane.
7. The electromagnetic tracking system of claim 6 , wherein the electromagnetic emitter further comprises a fourth phased array element, wherein the first phased array element, the second phased array element, and the third phased array element form three corners of a tetrahedron and the fourth phased array element forms a fourth corner of the tetrahedron.
8. A method of determining a six degree of freedom (DoF) pose of a handheld controller, the method comprising:
determining a pose of an electromagnetic sensor;
generating an electromagnetic beam from the handheld controller, wherein the electromagnetic beam is characterized by an electromagnetic field pattern;
steering the electromagnetic beam to increase received power at the electromagnetic sensor;
determining a beam angle associated with the electromagnetic beam;
determining a distance between the handheld controller and the electromagnetic sensor; and
determining the six DoF pose of the handheld controller using the pose of the electromagnetic sensor, the beam angle, and the distance.
9. The method of claim 8 , wherein the handheld controller includes an electromagnetic emitter, the electromagnetic emitter including:
a first phased array element configured to operate with a first phase; and
a second phased array element configured to operate with a second phase.
10. The method of claim 9 , wherein the electromagnetic emitter further includes a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane.
11. The method of claim 8 , wherein the pose of the electromagnetic sensor comprises a head pose and the electromagnetic sensor is an element of an AR headset.
12. The method of claim 8 , wherein steering the electromagnetic beam comprises aligning a central vector of the electromagnetic beam with a vector from the handheld controller to the electromagnetic sensor.
13. The method of claim 8 , wherein steering the electromagnetic beam to increase received power at the electromagnetic sensor comprises maximizing received power at the electromagnetic sensor.
14. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising:
determining a pose of an electromagnetic sensor;
generating an electromagnetic beam from a handheld controller, wherein the electromagnetic beam is characterized by an electromagnetic field pattern;
steering the electromagnetic beam to increase received power at the electromagnetic sensor;
determining a beam angle associated with the electromagnetic beam;
determining a distance between the handheld controller and the electromagnetic sensor; and
determining a six degree of freedom (DoF) pose of the handheld controller using the pose of the electromagnetic sensor, the beam angle, and the distance.
15. The non-transitory computer-readable medium of claim 14 , wherein the handheld controller includes an electromagnetic emitter, the electromagnetic emitter including:
a first phased array element configured to operate with a first phase; and
a second phased array element configured to operate with a second phase.
16. The non-transitory computer-readable medium of claim 15 , wherein the electromagnetic emitter further includes a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane.
17. The non-transitory computer-readable medium of claim 14 , wherein the pose of the electromagnetic sensor comprises a head pose and the electromagnetic sensor is an element of an AR headset.
18. The non-transitory computer-readable medium of claim 14 , wherein steering the electromagnetic beam comprises aligning a central vector of the electromagnetic beam with a vector from the handheld controller to the electromagnetic sensor.
19. The non-transitory computer-readable medium of claim 14 , wherein steering the electromagnetic beam to increase received power at the electromagnetic sensor comprises maximizing received power at the electromagnetic sensor.
20. An electromagnetic tracking system comprising:
a handheld controller including an electromagnetic emitter, the electromagnetic emitter including:
a first phased array element characterized by a first phase; and
a second phased array element characterized by a second phase different than the first phase;
a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane; and
a fourth phased array element, wherein the first phased array element, the second phased array element, and the third phased array element form three corners of a tetrahedron and the fourth phased array element forms a fourth corner of the tetrahedron;
wherein the first phased array element, the second phased array element, the third phased array element, and the fourth phased array element are configured to generate a steerable electromagnetic beam characterized by an electromagnetic field pattern; and
a head mounted augmented reality display including an electromagnetic sensor configured to sense the electromagnetic field pattern.