Systems and methods of object detection in wireless power charging systems

Patent metadata

Field	Value
Publication number	US-10270261-B2
Application number	US-201615053124-A
Country	US
Kind code	B2
Filing date	Feb 25, 2016
Priority date	Sep 16, 2015
Publication date	Apr 23, 2019
Grant date	Apr 23, 2019

Abstract

Embodiments disclosed herein discloses a wireless charging system configured to generate and transmit power waves that, due to physical waveform characteristics converge at a predetermined location in a transmission field to generate a pocket of energy. Receivers associated with an electronic device being powered by the wireless charging system, may extract energy from these pocket of energy and then convert that energy into usable electric power for the electronic device associated with a receiver. The pocket of energy may manifest as a three-dimensional field (e.g., transmission field) where energy may be harvested by a receiver positioned within or nearby the pocket of energy. Video sensors capture actual video images of fields of view within the transmission field, and a processor identifies selected objects, selected events, and/or selected locations within the captured video images.

First claim

What is claimed is:

1. A method for wireless power transmission comprising:
transmitting, by a transmitter, radio frequency (RF) power waves that converge to form constructive interference at a location associated with a receiver;
receiving, from at least one thermal imaging camera in communication with the transmitter, a thermal image of at least a portion of a transmission field of the transmitter;
identifying, by the transmitter, a living being within a field of view of the at least one thermal imaging camera, the field of view including at least the transmission field of the transmitter, and the living being is identified based upon temperature data in the thermal image;
after transmitting the RF power waves that converge to form constructive interference at the location associated with the receiver, determining, by the transmitter, a proximity of the identified living being to the RF power waves; and
adjusting, by the transmitter, a power level of the RF power waves upon determining that the proximity of the living being is within a predefined distance from the RF power waves.

2. The method of claim 1 , wherein the predefined distance corresponds to distance from the living being to the receiver.

3. The method of claim 1 , wherein the at least one thermal imaging camera generates the thermal image of its field of view overlapping the transmission field of the transmitter, and wherein the temperature data of the thermal image corresponds to visually contiguous body temperature pixels.

4. The method of claim 1 , wherein identifying the living being further comprises detecting information relating to the presence of the living being within the transmission field of the transmitter based upon the temperature data.

5. The method of claim 4 , wherein the information relating to presence of the living being based upon the thermal imaging data comprises one or more of face detection information, head detection information, hand detection information, skin detection information, human shape information, human appearance patterns, human biometric attributes, human motion information, and human activity information.

6. The method of claim 1 , further comprising generating, by a plurality of thermal imaging cameras in communication with the transmitter, a plurality of thermal images of their corresponding plurality of field of views overlapping the transmission field of the transmitter.

7. The method of claim 1 , wherein movement of the living being towards the transmitter is detected by identifying a growing pattern of visually contiguous body temperature pixels in the at least one thermal image over a period of time.

8. The method of claim 7 , further comprising reducing, by the transmitter, the power level of the RF power waves based on the detection of movement of the growing pattern of visually contiguous body temperature pixels in the thermal image over the period of time towards the transmitter.

9. The method of claim 7 , further comprising terminating, by the transmitter, the RF power waves based on the detection of movement of the growing pattern of visually contiguous body temperature pixels in the thermal image over the period of time towards the transmitter.

10. A transmitter for wireless power transmission comprising:
a thermal imaging camera configured to generate a thermal image of at least a portion of a transmission field of the transmitter;
a controller configured to: (i) receive a thermal image from the thermal imaging camera, (ii) identify a living being in the transmission field of the transmitter based upon temperature data in the thermal image, (iii) determine a proximity of the identified living being to RF power waves generated by the transmitter after transmitting the RF power waved that converge to form constructive interference at the location associated with the receiver, and (iv) adjust a power level of the RF power waves upon determining that the proximity of the living being is within a predefined distance from RF the power waves.

11. The transmitter of claim 10 , wherein the predefined distance corresponds to distance from the living being to the transmitter.

12. The transmitter of claim 10 , wherein the predefined distance corresponds to distance from the living being to the receiver.

13. The transmitter of claim 10 , wherein the thermal imaging camera generates the thermal image of its field of view overlapping the transmission field of the transmitter, and wherein the temperature data of the thermal image corresponds to visually contiguous body temperature pixels.

14. The transmitter of claim 10 , wherein the identification of the living being further comprises the controller detecting information relating to the presence of the living being within the transmission field of the transmitter based upon the temperature data.

15. The transmitter of claim 14 , wherein the information relating to presence of the living being based upon the thermal imaging data comprises one or more of face detection information, head detection information, hand detection information, skin detection information, human shape information, human appearance patterns, human biometric attributes, human motion information, and human activity information.

16. The transmitter of claim 10 , further comprising a plurality of thermal imaging cameras in communication with the transmitter to generate a plurality of thermal images of their corresponding plurality of field of views overlapping the transmission field of the transmitter.

17. The transmitter of claim 10 , wherein movement of the living being towards the transmitter is detected by identifying a growing pattern of visually contiguous body temperature pixels in the thermal image over a period of time.

18. The transmitter of claim 17 , wherein the controller is configured to reduce the power level of the power waves based on the detection of movement of the growing pattern of visually contiguous body temperature pixels in the thermal image over the period of time towards the transmitter.

19. The transmitter of claim 17 , wherein the controller is configured to terminate the power waves based on the detection of movement of the growing pattern of visually contiguous body temperature pixels in the thermal image over the period of time towards the transmitter.

20. The method of claim 1 , further comprising, before the receiving:
detecting a trigger signal; and
in response to detecting the trigger signal, instructing the at least one thermal imaging camera to capture the thermal image.

Assignees

• Energous Corp

Inventors

• Bell Douglas
• Leabman Michael A

Classifications

• H02J7/42

  with electronic devices having internal batteries, e.g. mobile phones · CPC title

• H02J50/15

  using ultrasonic waves · CPC title

• H02J50/80

  involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices · CPC title

• G06T7/60

  Analysis of geometric attributes · CPC title

• H02J50/60

  responsive to the presence of foreign objects, e.g. detection of living beings · CPC title