Systems and methods for synchronizing lighting devices

• US 10,187,958 B2
• Filed: 03/22/2017
• Issued: 01/22/2019
• Est. Priority Date: 08/11/2015
• Status: Active Grant

• Current Assignee: Signify North America Corporation (Signify N.V.)
• Original Assignee: Philips Lighting BV (Koninklijke Philips N.V.)
• Inventors: Joseph, Neil
• Primary Examiner(s): Owens, Douglas W
• Assistant Examiner(s): Kaiser, Syed M
• Application Number:
  US15/466,340
• Publication Number:
  US 20170196067A1
• Time in Patent Office: 671 Days
• Field of Search: 315307, 315297, 315312
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/325 Pulse-width modulation [PWM]
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

Systems and methods are provided for synchronizing a plurality of lighting devices. One or more potential-interference-neighbor (PIN) lighting devices are identified near a master lighting device. The master lighting device outputs a first lighting signal and the one or more PIN lighting devices output one or more second lighting signals. One or more time offsets between the first lighting signal and the one or more second lighting signals are determined. The one or more second lighting signals are adjusted based at least in part on the one or more time offsets to synchronize the first lighting signal and the one or more second lighting signals.

Claims

1. A method for synchronizing a plurality of lighting devices, the method comprising:

determining one or more time off sets between a first lighting signal output by a first lighting device and the one or more second lighting signals from one or more other lighting devices; and

adjusting the one or more second lighting signals based at least in part on the one or more time offsets to synchronize the first lighting signal and the one or more second lighting signals.

2. The method of claim 1, further comprising:

identifying the one or more other lighting devices, which are potential-interference-neighbor (PIN) lighting devices, near the first lighting device, which is a master lighting device;

wherein the master lighting device outputs the first lighting signal and the one or more PIN lighting devices output the one or more second lighting signals;

wherein the one or more PIN lighting devices are identified based at least in part on received signal strength indication (RSSI) associated with the one or more PIN lighting devices.

3. The method of claim 2 wherein the one or more PIN lighting devices have higher RSSI than other lighting devices near the master lighting device.

4. The method of claim 1 wherein determining the one or more time offsets between the first lighting signal and the one or more second lighting signals includes:

performing an ambient light measurement; and

determining the one or more time offsets based at least in part on the ambient light measurement.

5. The method of claim 4 wherein the ambient light measurement is performed using an ambient light sensor associated with a master lighting device.

6. The method of claim 4 wherein the first lighting signal and the one or more second lighting signals are not synchronized during the one or more time offsets.

7. The method of claim 2 wherein performing the ambient light measurement includes:

turning off all lighting devices near the master lighting device except the one or more PIN lighting devices.

8. The method of claim 1 wherein the one or more time offsets are approximately equal to zero when the first lighting signal and the one or more second lighting signals are synchronized.

9. The method of claim 1 wherein determining the one or more time off sets between the first lighting signal and the one or more second lighting signals includes:

determining a first time at which the first lighting signal changes from logic high to logic low; and

determining one or more second times at which the one or more second lighting signals change from logic high to logic low;

wherein the one or more time off sets correspond to the difference between the first time and the one or more second times.

10. The method of claim 2 wherein the first lighting device includes one or more light emitting diodes.

11. The method of claim 1, further comprising:

repeating the determining step and the adjusting step until the first lighting signal and the one or more second lighting signals are synchronized.

12. The method of claim 2, further comprising:

selecting a first PIN lighting device from the one or more PIN lighting devices;

determining a first time offset between the first lighting signal and a third lighting signal output by the first PIN lighting device; and

adjusting the third lighting signal based at least in part on the first time offset to synchronize the first lighting signal and the third lighting signal.

13. The method of claim 12, further comprising:

selecting a second PIN lighting device from the one or more PIN lighting devices;

determining a second time off set between the first lighting signal and a fourth lighting signal output by the second PIN lighting device; and

adjusting the fourth lighting signal based at least in part on the second time offset to synchronize the first lighting signal and the fourth lighting signal.

14. The method of claim 13 wherein the second PIN lighting device has a higher RSSI than the first PIN lighting device.

15. A processor-implemented system for synchronizing a plurality of lighting devices, the system comprising:

one or more data processors; and

one or more non-transitory computer-readable storage media encoded with instructions for commanding the one or more data processors to execute operations including;

determining one or more time off sets between a first lighting signal output by a first lighting device and one or more second lighting signals from one or more other lighting devices; and

adjusting the one or more second lighting signals based at least in part on the one or more time off sets to synchronize the first lighting signal and the one or more second lighting signals.

16. The system of claim 15, wherein the operations further comprise:

identifying the one or more other lighting devices, which are potential-interference-neighbor (PIN) lighting devices, near the first lighting device, which is a master lighting device;

wherein the master lighting device outputs the first lighting signal and the one or more PIN lighting devices output the one or more second lighting signals;

wherein the one or more PIN lighting devices are identified based at least in part on received signal strength indication (RSSI) associated with the one or more PIN lighting devices.

17. The system of claim 16 wherein the one or more PIN lighting devices have higher RSSI than other lighting devices near the master lighting device.

18. The system of claim 15 wherein determining the one or more time offsets between the first lighting signal and the one or more second lighting signals includes:

performing an ambient light measurement; and

determining the one or more time offsets based at least in part on the ambient light measurement.

19. The system of claim 18 wherein the ambient light measurement is performed using an ambient light sensor associated with the first lighting device.

20. A non-transitory machine-readable storage medium encoded with instructions for commanding one or more data processors to execute operations of a method for synchronizing a plurality of lighting devices, the method comprising:

determining one or more time off sets between a first lighting signal output by a first lighting device and one or more second lighting signals from one or more other lighting devices; and

adjusting the one or more second lighting signals based at least in part on the one or more time offsets to synchronize the first lighting signal and the one or more second lighting signals.