Sensor for detecting glare conditions

Patent metadata

Field	Value
Publication number	US-12163376-B2
Application number	US-202117539025-A
Country	US
Kind code	B2
Filing date	Nov 30, 2021
Priority date	Nov 30, 2020
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A sensor and/or system controller may process an image multiple times at multiple resolutions to detect glare conditions. A glare condition threshold used to determine whether a glare condition exists may be based on the resolution of the image. When the resolution of the image is higher, the glare condition threshold may be higher. The sensor and/or system controller may organize one or more adjacent pixels having similar intensities into pixel groups. The pixel groups may vary in size and/or shape. The sensor and/or system controller may determine a representative group luminance for the pixel group (e.g., an average luminance of the pixels in the group). The sensor and/or system controller may determine a group glare condition threshold, which may be used to determine whether a glare condition exists for the group of pixels and/or may be based on the size of the group.

First claim

What is claimed is:

1. An apparatus for detecting a location of a glare condition and for controlling a position of a motorized window treatment, the system controller comprising:
a control circuit configured to:
determine a desired position based on an indication of a location of a glare condition in an image;
determine a difference between the desired position and a present position;
compare the difference to at least one of a first threshold and a second threshold; and
transmit control instructions for controlling the position of the motorized window treatment to the desired position if the difference is greater than or equal to the first threshold or less than or equal to the second threshold;
wherein the first threshold is a raise threshold, the second threshold is a lower threshold, and wherein the control instructions are configured to instruct the motorized window treatment to raise the position if the difference is greater than or equal to the first threshold or to lower the position if the difference is less than or equal to the second threshold.

2. The apparatus of claim 1 , further comprising a communication circuit, wherein the control circuit is configured to transmit the control instructions via the communication circuit.

3. The apparatus of claim 1 , wherein the control instructions are configured to instruct the motorized window treatment to adjust the position to match the desired position.

4. The apparatus of claim 1 , wherein the control circuit being configured to determine the desired position comprises the control circuit being configured to:
process at least one image at a plurality of resolutions,
determine if a glare condition exists in the at least one image at each of the plurality of resolutions, wherein the glare condition at each of the plurality of resolutions is determined when a luminance value of a pixel in the at least one image exceeds a respective glare condition threshold for the resolution, and
determine the desired position to be a position corresponding to a location of the glare condition detected at one of the plurality of resolutions.

5. A method of detecting a location of a glare condition and for controlling a position of a motorized window treatment, the method comprising:
determining a desired position based on an indication of a location of a glare condition in an image;
determining a difference between the desired position and a present position;
comparing the difference to at least one of a first threshold and a second threshold; and
transmitting control instructions for controlling the position of the motorized window treatment to the desired position if the difference is greater than or equal to the first threshold or less than or equal to the second threshold;
wherein the first threshold is a raise threshold, the second threshold is a lower threshold, and wherein the control instructions are configured to instruct the motorized window treatment to raise the position if the difference is greater than or equal to the first threshold or to lower the position if the difference is less than or equal to the second threshold.

6. The method of claim 5 , wherein the control instructions are configured to instruct the motorized window treatment to adjust the position to match the desired position.

7. The method of claim 5 , wherein determining the desired position comprises:
processing at least one image at a plurality of resolutions,
determining if a glare condition exists in the at least one image at each of the plurality of resolutions, wherein the glare condition at each of the plurality of resolutions is determined when a luminance value of a pixel in the at least one image exceeds a respective glare condition threshold for the resolution, and
determining the desired position to be a position corresponding to a location of the glare condition detected at one of the plurality of resolutions.

8. An apparatus for detecting a location of a glare condition and for controlling a position of a motorized window treatment, the apparatus comprising:
a control circuit configured to:
determine a desired position based on an indication of a location of a glare condition in an image;
determine that the desired position is higher than a present position;
determine that a raise timeout period has occurred since the last adjustment of the position of the motorized window treatment; and
upon the determination that the raise timeout period has occurred since the last adjustment of the position of the motorized window treatment, transmit control instructions for controlling the position of the motorized window treatment to the desired position.

9. The apparatus of claim 8 , wherein the control instructions are configured to instruct the motorized window treatment to raise the position to match the desired position.

10. The apparatus of claim 8 , wherein the apparatus further comprises a timer, and wherein the timer is configured to be started following a previous determination of a desired shade position.

11. The apparatus of claim 10 , wherein after the control instructions are transmitted for controlling the position, the control circuit is further configured to:
reset the timer; and
restart the timer.

12. The apparatus of claim 8 , wherein the control circuit is further configured to:
determine a second desired position;
determine that the second desired position is lower than a second present position; and
transmit control instructions for controlling the position of the motorized window treatment.

13. The apparatus of claim 12 , wherein the control instructions are configured to instruct the motorized window treatment to lower the position to match the second desired position.

14. The apparatus of claim 12 , wherein the apparatus further comprises a timer, and wherein the control circuit is further configured to:
reset the timer; and
restart the timer.

15. The apparatus of claim 8 , wherein the image comprises a plurality of pixels, and wherein the control circuit being configured to determine the desired position comprises the control circuit being configured to:
determine that a luminance value of a pixel in the image exceeds a glare condition threshold;
determine a location of the pixel;
determine a profile angle based on the location of the pixel; and
determine the desired position based on the profile angle.

16. The apparatus of claim 8 , wherein the image comprises a plurality of pixels, and wherein control circuit being configured to determine the desired position comprises the control circuit being configured to:
determine an illuminance value for a pixel in the image;
add the illuminance value for the pixel to a cumulative illuminance value for the image;
determine that the cumulative illuminance value exceeds a glare condition threshold;
determine a location of the pixel;
determine a profile angle based on the location of the pixel; and
determine the desired position based on the profile angle.

17. An apparatus for detecting a location of a glare condition and for controlling a position of a motorized window treatment, the apparatus comprising:
a control circuit configured to:
determine a desired position based on an indication of a location of a glare condition in an image;
determine whether the desired position is higher than a present position;
determine that a raise timer has started, wherein the raise timer is configured to reduce a number of adjustments made to the position by decreasing a frequency at which the position is adjusted;
determine whether the raise

Assignees

• Lutron Tech Co Llc

Inventors

• Casey Craig Alan
• Venkata Gopalan Yogesh
• Protzman Brent

Classifications

• G01J2001/4266

  for measuring solar light · CPC title

• G01J1/4204

  with determination of ambient light (solar light G01J2001/4266) · CPC title

• E06B2009/6827

  sensing light · CPC title

• E06B2009/6818

  using sensors · CPC title

• E06B9/68 Primary

  Operating devices or mechanisms, e.g. with electric drive · CPC title