Sensor web

• US 10,477,495 B2
• Filed: 06/07/2016
• Issued: 11/12/2019
• Est. Priority Date: 10/09/2002
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Delin, Kevin A., Jackson, Shannon
• Primary Examiner(s): Vu, Huy D
• Assistant Examiner(s): Ahmed, Nizam U
• Application Number:
  US15/175,965
• Publication Number:
  US 20160286505A1
• Time in Patent Office: 1,253 Days
• Field of Search: 370338
• CPC Class Codes: G01D 21/00 Measuring or testing not otherwise provided for
• CPC Class Codes: H04J 3/0641 Change of the master or reference, e.g. take-over or failure of the master
• CPC Class Codes: H04W 40/24 Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A Sensor Web formed of a number of different sensor pods. Each of the sensor pods include a clock which is synchronized with a master clock so that all of the sensor pods in the Web have a synchronized clock. The synchronization is carried out by first using a coarse synchronization which takes less power, and subsequently carrying out a fine synchronization to make a fine sync of all the pods on the Web. After the synchronization, the pods ping their neighbors to determine which pods are listening and responded, and then only listen during time slots corresponding to those pods which respond.

Claims

1. A method, comprising:

deploying a plurality of sensor pods having a specified hardware characteristic and forming a sensor web;

establishing wireless communications between a sensor pod of the plurality of sensor pods and a first set of sensor pods of the plurality of sensor pods that are only within a communication range of the sensor pod, the first set of sensor pods then processing data from the wireless communications and then broadcasting post-processed data to a second set of sensor pods that are only within a separate communication range of the first set of sensor pods;

activating spaced sensor pods of said plurality to carry out a specified operation at each of a plurality of spaced locations; and

evolving the sensor web by adding, while the sensor web is in operation, more sophisticated sensor pods which have an additional hardware characteristic than said specified hardware characteristic;

wherein the processing data comprises extending a range or sensitivity of a given sensor pod by applying spatio-temporal trending by measuring and tracking spatio-temporal gradients of sensor pods measurements.

2. The method as in claim 1, further comprising:

synchronizing said spaced sensor pods such that said spaced sensor pods each include a synchronized clock; and

using said synchronized clock to synchronize said spaced sensor pods to determine a parameter at times that are based on said synchronized clock.

3. The method as in claim 2, wherein said using comprises causing said spaced sensor pods to each determine the parameter at precisely the same time and at said different locations.

4. The method as in claim 2, wherein said synchronizing comprises

first carrying out a coarse synchronization which coarsely synchronizes said spaced sensor pods while minimizing an amount of consumed power,

and second carrying out a fine synchronization which more finely synchronizes said sensor pods.

5. The method as in claim 2, further comprising sharing information among all of said spaced sensor pods such that all of said spaced sensor pods receive information about all of the parameters sensed at each of the spaced locations.

6. The method as in claim 2, further comprising a ping routine, during which each of the spaced sensor pods determine which other sensor pods respond to pings and time slots assigned to said other sensor pods, and wherein each sensor pod listens to other sensor pods only during said time slots.

7. The method as in claim 2, further comprising adding another sensor pod to the sensor web during operation of the sensor web.

8. The method as in claim 7, further comprising, after adding said another sensor pod, synchronizing a clock within said another sensor pod with said synchronized clock.

9. The method as in claim 2, wherein said synchronizing comprises carrying out a first, coarse synchronization at reduced power consumption, and subsequently carrying out a second, fine synchronization, at a higher power consumption.

10. The method as in claim 2, further comprising using said synchronized clock to carry out a main processing loop in each of said plurality of sensor pods which both starts and ends at substantially the same time.

11. The method of claim 1, further comprising sending an event-trigger to each sensor pod of the plurality of sensor pods.

12. The method of claim 11, wherein the event-trigger is a wake-up trigger for dormant sensor pods.

13. The method of claim 11, wherein the event-trigger is for changing a measurement cycle of a sensor pod.

14. The method of claim 1, wherein the processing data comprises combining scalar information into vector information.

15. The method of claim 1, further comprising connecting the sensor web to pingers.

16. The method of claim 15, wherein the pingers are RF tags.