Wireless mine tracking, monitoring, and rescue communications system

• US 8,294,568 B2
• Filed: 07/10/2007
• Issued: 10/23/2012
• Est. Priority Date: 07/10/2006
• Status: Expired due to Fees

• Current Assignee: Venture Corporation Limited
• Original Assignee: Venture Corporation Limited
• Inventors: Barrett, James P.
• Primary Examiner(s): Zimmerman, Brian
• Assistant Examiner(s): Samson, Sara
• Application Number:
  US11/775,831
• Publication Number:
  US 20080137589A1
• Time in Patent Office: 1,932 Days
• Field of Search: 340/539.1, 340/500, 340/531, 340/539.11
• US Class Current: 340/539.11
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04M 3/42348 Location-based services which utilize the location information of a target
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 4/18 Information format or content conversion, e.g. adaptation by the network of the transmitted or received information for the purpose of wireless delivery to users or terminals
• CPC Class Codes: H04W 4/33 for indoor environments, e.g. buildings
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 76/50 for emergency connections
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

An intrinsically safe accurate location information network for personnel and assets in underground mines, including wireless access points and subnetwork controllers, active wireless locator/messenger tags, network controller(s), and enterprise servers running application control software. The wireless access points are installed in mine entries and crosscuts and track the active wireless locator/messenger tags. The active tags may be worn by mine personnel or installed in mining equipment. The network subsystems form relay networks that wirelessly carry telemetry and control data without the need to penetrate the earth. The subsystems determine the location of persons and assets underground and monitor safety-related information, which can be used for disaster avoidance, early warning of impending disaster, and improved rescue effectiveness.

Claims

1. A wireless mine monitoring, tracking, and communications network, comprising:

at least one network controller installed at the mine office level and running application control software for remotely monitoring all connected devices in the network;

a plurality of active wireless transponders wearable by personnel entering and exiting mines and/or installable on equipment moving into, used throughout, and exiting mines, wherein said wireless transponders include transceivers;

at least one location subnet controller in wireless or wired or a combination of wired and wireless electronic communication with one or more of said at least one network controller and having an integral battery power supply;

a plurality of wireless access points, each in wireless communication with at least one of said subnet controllers, said wireless access points installed at the field level in the entries and crosscuts of an underground mine, said wireless access points also in wireless communication with said active wireless transponders for tracking said active wireless transponders and for making emergency communications available to miners, each of said wireless access points having an integral battery power supply; and

an automatic self-healing system for automated self-healing fail-over in the event that one of said plurality of wireless access points fails to function, said automatic self-healing system including at least a hop-over link recovery system;

wherein said plurality of active wireless transponders, said plurality of wireless access points, said at least one location subnet controller, and said at least one network controller are linked with one another through bi-directional network communications links, said bi-directional communications links including bi-directional voice and data communications to provide full-duplex streaming of voice data across a hierarchical mesh network topology;

wherein in the event of a catastrophic emergency that destroys a portion of said network, such that at least one of said wireless access points or subnet controllers fails to function, or when there is an accident that disrupts the primary or normal path of data transfer, said automatic self-healing system applies a rerouting/recovery/and failover mechanism;

and wherein said integral battery power supply, said active wireless transponders, said wireless access points, and said at least one location subnet controller are intrinsically safe.

2. The network of claim 1, further including at least one enterprise server installed at the corporate office level, said enterprise server running application software for said system and having a broadband network connection to said network controllers, wherein said application software enables monitoring of a plurality of mines via a global network system.

3. The network of claim 1, wherein said subnet controllers are in wired or wireless communication, including the transmission of voice communications, with at least one wireless access point in a distributed hierarchical architecture in which said subnet controllers are in communication with each other and said at least one network controller to orchestrate complex rapid processing required for life-saving with predictable high performance on large scales.

4. The network of claim 3, wherein said subnet controllers are un-tethered wireless peer-to-peer radio/computer subsystems.

5. The network of claim 4, wherein said un-tethered wireless peer-to-peer radio/computer subsystems are low power battery powered digital radios.

6. The network of claim 4, wherein said un-tethered wireless peer-to-peer radio/computer subsystems utilize high level communications protocol devised for use with compact low-power digital radios based on a standard accepted for wireless personal area networks (WPANs), and having a long battery life and secure networking.

7. The network of claim 1, further including a plurality of permanently mounted active wireless transponder devices disposed in fixed locations throughout a mine for performing system calibration and self-testing functions.

8. The network of claim 1, wherein said application software logs the status and communications of all active wireless transponders along with their physical location.

9. The network of claim 1, wherein said application software self-monitors health-check parameters for continuously assessing network status, such that when predetermined thresholds are reached, said system software automatically takes corrective action, triggers alarms as appropriate, issues trouble alerts, and manages all connected devices in said network.

10. The network of claim 1, further including at least one handheld location sniffer for detecting and identifying beacon signals from an active wireless transponder.

11. The network of claim 1, wherein said subnet controllers and said wireless access points comprise backbone wireless subnetworks disposed in self-healing networks.

12. The network of claim 11, wherein said subnetwork consists of about 25 of said wireless access points covering approximately 5000 linear feet of tunnel entry and crosscut per subnetwork, wherein the number and spacing of said wireless access points is varies according to the tunnel propagation characteristics in each locale of each mine, according to tunnel height, width, undulations, bends, and other characteristics present in the tunnel environment, and further wherein the number and spacing of said wireless access points is determined with the aid of real-time link strength/quality measurement meter built into said wireless access points as the meter is employed during deployment.

13. The network of claim 1, wherein said subnet controllers and said wireless access points comprise backbone wireless subnetworks that are disposed in a double redundant topology.

14. The network of claim 1, further including at least one dedicated subnet controller programmed with high speed sweep application software for rapidly determining the location of large numbers of miners in congested areas.

15. The network of claim 1, wherein said wireless access points are powered using hybrid battery-plus-wired-power circuits.

16. The network of claim 1, further including a rapid deployment all-battery version of said network for healing a portion of said network in a worst-case post-accident failure of some part of said network.

17. The network of claim 1, wherein said application software provides a user interface accessible via any standard client-based web-browser, and further wherein said application software runs in a standalone mode to provide a user interface when disconnected from a global communications network.

18. The network of claim 17, wherein said user interface views are organized to provide location data including active wireless transponder symbols populating a graphical mine map, and said user interface allows drag-and-drop of wireless transponder symbols onto said graphical mine map for intuitive rendering of location information, miner identity and status.

19. The network of claim 18, wherein said application software includes means for drill-down into progressively higher levels of detail of said graphical mine map.

20. The network of claim 1, wherein said plurality of wireless access points includes portable wireless access points and pre-installed fixed wireless access points, and wherein said application software differentiates said portable wireless access points from said pre-installed fixed wireless access points, such that at least some of said portable wireless access points may comprise a new subnet that the network can adopt, and further including a portable rapid-deployment network of all-battery-powered nodes capable of operating in RescueComm or ReachComm mode, to provide full-roaming voice services and data services through at least said new subnet.

21. The network of claim 1, wherein said network is automatically self-aware of the status and location of all elements comprising said network.

22. The network of claim 1, further including location estimating means including means to measure RSSI between said plurality of active wireless transponders and each and all of said wireless access points in said plurality of wireless access points within the variable range of said active wireless transponders.

23. The network of claim 22, wherein said location estimating means further includes means to measure LQI between said plurality of active wireless transponders and each and all of said wireless access points in said plurality of wireless access points within the variable range of said active wireless transponders.

24. The network of claim 23, wherein said automatic location estimating means includes automated RF self-calibration means for using the known approximate distance between one of said plurality of wireless access points and one of said plurality of active wireless transponders to calibrate the RSSI measurements.

25. An intrinsically-safe wireless mine monitoring, tracking, and communications network, comprising:

at least one network controller running application control software;

at least one location subnet controller running application control software and acting as a distributed compute-center in bi-directional electronic communication with one or more of said at least one network controller;

a plurality of active wireless transponders wearable by personnel entering and exiting mines and/or installable on equipment moving into, used throughout, and exiting mines, wherein said wireless transponders include two-way voice and/or text and/or location services transceivers;

a plurality of wireless access points in bi-directional wireless communication with each other and with at least one of said subnet controllers, said wireless access points installed at the field level in at least the entries and crosscuts of an underground mine, said wireless access points also in bi-directional wireless communication with said active wireless transponders for tracking said active wireless transponders and for making emergency communications available to miners and rescuers;

an energy efficient power supply and power-design incorporating intelligent sleep functions capable of operating for at least several days on small intrinsically safe batteries; and

a set of permanently mounted tags in fixed locations throughout the mine as calibrators that provide self-report reference points at known locations;

wherein said application control software utilizes said subnet controllers, wireless access points, active transponders, and permanently mounted tags to provide precise location determination routinely updated mine-wide for all miners wearing an active transponder, said location determination means including at least,

(a) precise algorithms utilizing RSSI plus LQI, plus RF vector-gradient, combined to perform probabilistic triangulation calculations to mitigate errors in ordinary RSSI algorithms,

(b) system self-calibration using real-time statistical analysis of actual tunnel RF parametrics including at least absorptive loss effects, multipath, other constructive/destructive interference effects, waveguide effects, tunnel bend effects, blockages/stoppings, and other sources of aliasing, so as to reduce common sources of error that otherwise limit the accuracy that can be achieved using ordinary RF propagation models for underground tunnels,

(c) human movement heuristics, knowledge of specific wearer characteristics, tunnel boundary and stopping data, filtering, and time averaging in algorithms optimized for precise location in underground mining;

wherein said location determination means provides high-precision miner location capability which is able to locate miners within 2-25 meters;

and further wherein said network uses a hierarchical distributed computing architecture and an orchestrated pull protocol running on backbone wireless subnetworks, each of said subnetworks including a plurality of wireless access points to cover a predetermined length of tunnel entry and crosscut, such that said network is scalable to any size mine and real-world mine-wide load.

26. The network of claim 25, further including system redundancy and smart command failover/corrective-action to each and every network element such that said network has structural and system integrity sufficient to survive mine accidents with greater than 90% functionality remaining after such accidents.

27. The network of claim 25, wherein said network is enabled for use with either a low bandwidth backhaul, including twisted-pair RS485 or Through-The-Earth wireless, or a high bandwidth backhaul, including fiber optic, wireless peer-to-peer, coaxial cable, Ethernet, and/or any combination thereof.