Asset tracking using active wireless tags that report via a local network of connected beacons

• US 10,346,649 B2
• Filed: 01/09/2018
• Issued: 07/09/2019
• Est. Priority Date: 01/11/2017
• Status: Active Grant

• Current Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Original Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Inventors: Lu, Yenpao, Green, Kelby Edward, Malandrakis, Emanuel Paul, George, Sajin, Abou-Rizk, Mitri J., Li, Xiangrong
• Primary Examiner(s): Garcia, Santiago
• Application Number:
  US15/865,801
• Publication Number:
  US 20180196972A1
• Time in Patent Office: 546 Days
• Field of Search: 340 101
• CPC Class Codes: G01S 5/019 Energy consumption
• CPC Class Codes: G06K 19/0716 at least one of the integrated circuit chips comprising a sensor or an interface to a sensor
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10158 methods and means used by the interrogation device for reliably powering the wireless record carriers using an electromagnetic interrogation field
• CPC Class Codes: G06K 7/10198 setting parameters for the interrogator, e.g. programming parameters and operating modes
• CPC Class Codes: G06K 7/10207 parameter settings related to power consumption of the interrogator
• CPC Class Codes: G06K 7/1091 means to wake up the scanner from a sleep mode, e.g. using an acceleration sensor indicating that the scanner is being picked up by a user
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: H04W 52/0274 by switching on or off the equipment or parts thereof
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A tag is configured to provide information that enables a processor or other computing device to locate the tag and any asset associated with the tag in an area. The tag incorporates a motion sensor responsive to movements of the tag above a predetermined rate and a predetermined magnitude. In response to the movements above the predetermined rate and magnitude, the motion sensor generates a voltage exceeding a predetermined threshold. An energy-saving process exploits the tag'"'"'s microcontroller'"'"'s transitions between a “sleep” state and an “awake” state. While asleep, the microcontroller maintains a clock and data in memory, and monitors an input from the motion sensor. In response to voltages at the input over the predetermine threshold, the microcontroller receives signals from one or more nearby beacon nodes in a network operating in the area, process the signals and transmit information based on the processed signals, for a position determination.

Claims

1. A tag comprising:

a radio frequency transceiver;

a power supply; and

a processing device configured, upon execution of instructions maintained in firmware to;

in response to expiration of a time period or an occurrence of event, exit a sleep mode, wherein the sleep mode is a low power consumption mode;

upon exiting the sleep mode, enter an awake mode;

receive radio frequency signals transmitted by one or more lighting devices in a network of lighting devices, wherein each of the respective one or more lighting devices transmitting the radio frequency signals includes a device identifier of the lighting device that transmitted the signal;

measure a received signal strength indicator of the radio frequency signals;

associate the received signal strength indicator of the radio frequency signals with the device identifier included in the signal;

transmit the associated device identifier of the one or more lighting devices in the network as a data packet to a computing device for determination of a position of the tag;

upon transmission of the data packet exit the awake mode; and

enter the sleep mode.

2. The tag of claim 1, wherein the transmitted data packet further comprises the received signal strength associated with the device identifier included in the data packet.

3. The tag of claim 1, further comprising:

firmware configured to maintain program instructions for execution by the processing device.

4. The tag of claim 1, wherein the processing device is further configured to:

select the device identifier corresponding to a highest received signal strength indicator value of the number of received radio frequency signals for inclusion in the data packet.

5. A method, comprising:

in response to expiration of a time period or an occurrence of event, exiting a sleep mode by a processor of a smart tag device, wherein the sleep mode of the tag device is a low power consumption mode;

upon exiting the sleep mode, entering, by the tag device, an awake mode;

receiving while the smart tag device is in the awake mode at least one radio frequency signal from a respective one or more nodes in a network, wherein each of the one or more nodes in the network transmits a radio frequency signal that includes an identifier of the respective node in a network transmitting the radio frequency signal, and the one or more nodes in the network are lighting devices;

measuring a received signal strength indicator of each of the at least one radio frequency signal transmitted by each respective node;

generating a report with the node identifier and the received signal strength indicator of the respective node;

transmitting the report to a computing device for determination of a position of the smart tag device with respect to the node in the network;

exiting the awake mode; and

reentering the sleep mode.

6. The method of claim 5, further comprising:

receiving the transmitted report by the computing device; and

determining by the computing device a position of the tag within a site service area, the site service are including the network.

7. The method of claim 5, wherein the one or more nodes of lighting devices in the network are equipped with radio frequency transceivers for transmitting the radio frequency signals to the tag and between lighting devices in the network, and

the computing device is configured to:

determine the position of the tag based on a map of the lighting devices within the site service area.

8. A tag comprising:

a radio frequency transceiver;

a motion sensor responsive to movements of the tag;

a power supply; and

a microcontroller configured, upon execution of instructions maintained in firmware to;

in response to a movement detection signal received from the motion sensor indicating a movement by the tag, exit a sleep mode, wherein the sleep mode is a low power consumption mode;

upon exiting the sleep mode, enter an awake mode, wherein the awake mode is a higher power consumption mode than the sleep mode;

in the awake mode, set a movement status flag bit indicating a movement of the tag;

stores a time based on setting of the movement status flags

return to the sleep mode;

in response to receipt of a subsequent movement detection signal, enter the awake mode;

store a subsequent time based on receipt of the subsequent movement detection signal;

responsive to time between setting of the movement status flag and the subsequent time related to receipt of the subsequent movement detection signal being less than a time threshold, obtain information usable to generate an estimate of a position of the tag;

transmit the obtained information as a data packet, to a computing device for determination of a position of the tag;

upon transmission of the data packet, set the movement status flag to indicate no movement;

exit the awake mode; and

enter the sleep mode.

9. The tag of claim 8, wherein the movement detection signal is a signal over a predetermined voltage threshold.

10. The tag of claim 8, wherein the motion sensor is a shock sensor, the shock sensor configured to use power in the millivolt or milliamperes range, and responsive to movements of the apparatus.

11. The tag of claim 8, wherein the microcontroller is further configured to obtain information usable to generate an estimate of a position by performing functions to:

receive radio frequency signals transmitted by a device in a network of devices, wherein the device transmits a device identifier;

measure a received signal strength indicator of the received radio frequency signals;

associate the received signal strength indicator with the device identifier included in the respective received radio frequency signal; and

transmit the received signal strength indicator and the associated device identifier, as a data packet, to a computing device for determination of a position of the tag.

12. The tag of claim 8, wherein the microcontroller is further configured to obtain information usable to generate an estimate of a position by performing functions to:

receive radio frequency signals transmitted by a number of devices in a network of devices, wherein the device transmits a device identifier;

measure a received signal strength indicator for each of the number of received radio frequency signals;

select the device identifier corresponding to a highest received signal strength indicator of the number of received radio frequency signals; and

transmit the selected device identifier in a data packet to a computing device for determination of a position of the tag.

13. A method, comprising:

in response to a movement detection signal received from a motion sensor indicating a movement by a tag, exiting, by a microcontroller of the tag, a sleep mode, wherein the sleep mode is a low power consumption mode;

upon exiting the sleep mode, entering, by the microcontroller, an awake mode, wherein the awake mode is a higher power consumption mode than the sleep mode;

in the awake mode, setting a movement status flag bit indicating a movement of the tag;

storing a time based on setting of the movement status flag;

returning to the sleep mode;

in response to receipt of a subsequent movement detection signal, entering the awake mode;

storing a subsequent time based on receipt of the subsequent movement detection signal;

determining whether the time between the setting of the movement status flag and the subsequent time related to receipt of the subsequent movement detection signal was set less than a time threshold;

in response to a determination the time between setting of the movement status flag and the subsequent time related to receipt of the subsequent movement detection signal was less than the time threshold, receiving while the tag is in the awake mode at least one radio frequency signal from a respective one or more nodes in a network, wherein;

each of the one or more nodes in the network transmits a radio frequency signal that includes an identifier of the respective node in a network transmitting the radio frequency signal;

measuring a received signal strength indicator of each of the at least one radio frequency signal transmitted by each respective node;

generating a report with the node identifier and the received signal strength indicator of the respective node;

transmitting the report to a computing device for determination of a position of the tag with respect to the node in the network;

exiting the awake mode; and

reentering the sleep mode.

14. The method of claim 13, further comprising:

receiving the transmitted report by the computing device; and

determining by the computing device a position of the tag within a site service area, the site service are including the network.

15. The method of claim 13, wherein the one or more nodes in the network are lighting devices equipped with radio frequency transceivers for transmitting the radio frequency signals to the tag and between lighting devices in the network, and

the computing device is configured to:

determine the position of the tag based on a map of the lighting devices within the site service area.

16. A method, comprising:

in response to a movement detection signal received from a motion sensor indicating a movement by a tag, exiting, by a microcontroller of the tag, a sleep mode, wherein the sleep mode is a low power consumption mode;

upon exiting the sleep mode, entering, by the microcontroller, an awake mode, wherein the awake mode is a higher power consumption mode than the sleep mode;

in the awake mode, setting a movement status flag bit indicating a movement of the tag;

storing a time based on setting of the movement status flag;

returning to the sleep mode;

in response to receipt of a subsequent movement detection signal, entering the awake mode;

storing a subsequent time based on receipt of the subsequent movement detection signal;

determining whether the time between the setting of the movement status flag and the subsequent time related to receipt of the subsequent movement detection signal was set less than a time threshold;

in response to a determination the time between setting of the movement status flag and the subsequent time related to receipt of the subsequent movement detection signal was less than the time threshold, receiving while the tag is in the awake mode at least one radio frequency signal from a respective one or more nodes in a network, wherein;

each of the one or more nodes in the network transmits a radio frequency signal that includes an identifier of the respective node in a network transmitting the radio frequency signal;

measuring a received signal strength indicator of each of the at least one radio frequency signal transmitted by each respective node;

generating a report with the node identifier and without the received signal strength indicator of the respective node;

transmitting the report to a computing device for determination of a position of the tag with respect to the node in the network;

exiting the awake mode; and

reentering the sleep mode.

17. The method of claim 16, further comprising:

receiving the transmitted report by the computing device; and

determining by the computing device a position of the tag within a site service area, the site service are including the network.

18. The method of claim 16, wherein the one or more nodes in the network are lighting devices equipped with radio frequency transceivers for transmitting the radio frequency signals to the tag and between lighting devices in the network, and

the computing device is configured to:

determine the position of the tag based on a map of the lighting devices within the site service area.

19. A tag comprising:

a radio frequency transceiver;

a power supply; and

a processing device configured, upon execution of instructions maintained in firmware to;

in response to expiration of a time period or an occurrence of event, exit a sleep mode, wherein the sleep mode is a low power consumption mode;

upon exiting the sleep mode, entering an awake mode;

receive radio frequency signals transmitted by one or more lighting devices in a network of lighting devices, wherein each of the respective one or more lighting devices transmitting the radio frequency signals includes a device identifier of the lighting device that transmitted the signal;

measure a received signal strength indicator of the radio frequency signals;

associate the received signal strength indicator of the radio frequency signals with the device identifier included in the signal;

transmit only the associated device identifier of the one or more lighting devices in the network as a data packet to a computing device for determination of a position of the tag;

upon transmission of the data packet exit the awake mode; and

entering enter the sleep mode.