Method, controller, and system for tunnel communication

A communication system for allowing personnel in a tunnel below ground to communicate with a location above ground includes a controller disposed below ground in the tunnel. The system includes an uplink portion that sends uplink messages from the controller below ground in the tunnel through earth to above ground. The system includes a downlink portion through which downlink messages are sent from above ground through earth to the controller below ground in the tunnel. The system includes a personnel communication portion through which downlink messages are sent from the controller wirelessly to the personnel as personnel messages and personnel messages are received wirelessly by the controller from the personnel below ground in the tunnel. A controller for allowing personnel in a tunnel below ground to communicate with a location above ground. A method for allowing personnel in a tunnel below ground to communicate with a location above ground.

FIELD OF THE INVENTION

The present invention is related to a communication system for allowing personnel in a mine, tunnel or other space below ground to communicate with a location above ground. (As used herein, references to the “present invention” or “invention” relate to exemplary embodiments and not necessarily to every embodiment encompassed by the appended claims.) More specifically, the present invention is related to a communication system for allowing personnel below ground to communicate with a location above ground that includes a controller which controls message flow between the personnel below ground and above ground.

BACKGROUND OF THE INVENTION

This section is intended to introduce the reader to various aspects of the art that may be related to various aspects of the present invention. The following discussion is intended to provide information to facilitate a better understanding of the present invention. Accordingly, it should be understood that statements in the following discussion are to be read in this light, and not as admissions of prior art.

In mines, it is imperative that communication exists between the miners that are in the mine below ground and to people above ground. Specifically, in emergency situations, it is critical to be able to communicate with the miners to know whether they have been injured, where they are located, whether they are trapped, and whether they need food, water, air or first aid, to name but a few of the possible needs of the miners in such situations.

The problem that exists with communication in a mine is that the earth itself can impede communication between the miners in the mine as well as between the miners in the mine and people above the ground. Cabling or wiring has traditionally been used, but it requires a connection between the communication points. If the communication points are separated by a significant distance, it becomes problematic to extend the wiring such distances. Moreover, since mines are constantly expanding and changing shape, wiring is constantly being run to accommodate the changing distances and configurations of the mine. In addition, mines are hazardous places, with rockfall possibly damaging or cutting wires, which could be very dangerous in emergency situations where the communication is badly needed. Furthermore, it is impractical to extend wires to each miner in a mine to be able to communicate with each miner at any time. Although the specific need that gave rise to the invention was first identified in the mining industry, the utility of the invention could apply equally to emergency situations involving personnel in an underground work location, such as tunnels.

Wireless communication would eliminate the problems associated with using cabling or wiring for communication in a mine, but the very earth itself imposes difficulties on wireless communication between miners in the mine, and miners in the mine and people above ground.

BRIEF SUMMARY OF THE INVENTION

The present invention pertains to a communication system for allowing personnel in a tunnel below ground to communicate with a location above ground. The system comprises a controller disposed below ground in the mine. The system comprises an uplink portion that sends uplink messages from the controller below ground in the tunnel through the earth to above ground. The controller is in communication with the uplink portion. The system comprises a downlink portion through which downlink messages are sent from above ground through earth to the controller below ground in the tunnel. The controller is in communication with the downlink portion. The system comprises a personnel communication portion through which downlink messages are sent from the controller wirelessly to the personnel as personnel messages and personnel messages are received wirelessly by the controller from the personnel below ground in the tunnel. The controller is in communication with the personnel communication portion.

The present invention pertains to a method for allowing personnel in a tunnel below ground to communicate with a location above ground. The method comprises the steps of sending uplink messages from a controller through an uplink portion below ground in the tunnel through earth to above ground. The controller in communication with the uplink portion. There is the step of sending messages from above ground through earth to the controller through a downlink portion below ground in the tunnel, the controller in communication with the downlink portion. There is the step of sending from the controller through a personnel communication portion wirelessly to the personnel downlink messages as personnel messages. The controller in communication with the personnel communication portion. There is the step of receiving wirelessly by the controller from the personnel below ground in the tunnel personnel messages.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings wherein like reference numerals refer to similar or identical parts throughout the several views, and more specifically toFIGS. 1 and 2and3thereof, there is shown a communication system10for allowing personnel, such as miners, in a tunnel, for instance in a mine, below ground to communicate with a location above ground. The system10comprises a controller12disposed below ground in the tunnel. The system10comprises an uplink portion14that sends uplink messages from the controller12below ground in the tunnel through earth to above ground. The controller12in communication with the uplink portion14. The system10comprises a downlink portion16through which downlink messages are sent from above ground through earth to the controller12below ground in the tunnel. The controller12in communication with the downlink portion16of the system10comprises a personnel communication portion18through which downlink messages are sent from the controller12wirelessly to the personnel as personnel messages and personnel messages are received wirelessly by the controller12from the personnel below ground in the tunnel, the controller12in communication with the personnel communication portion18.

The controller12may be disposed in an intrinsically safe enclosure, such as an explosion proof enclosure20. The controller12may include a processing unit22which takes downlink messages received from the downlink portion16and transmits the downlink messages as personnel messages to the personnel, and which takes personnel messages received from the personnel communication portion18and transmits the personnel messages as uplink messages above ground through the uplink portion14. The controller12may include an uplink interface24through which uplink messages are provided to the uplink portion14, a downlink interface26through which downlink messages are received from the downlink portion16, and a personnel communication interface27through which personnel messages are sent to and received from the personnel communication portion18.

The processing unit22may broadcast out the downlink messages as personnel messages to all personnel through the personnel communication portion18. The personnel communication portion18may include a personnel communicator28disposed with each personnel that sends a response to each personnel message received from the controller12back to the controller12through the personnel communication portion18. The response may be either positive or negative, for instance red or green, respectively, and the processing unit22counts the responses that are green which were received over a predetermined time period and sends an uplink message at a frequency which corresponds to a number of responses counted in the predetermined time that are green which were received by the controller12.

The downlink portion16may use magnetic induction to send the above ground message to the tunnel. The uplink portion14may use seismic waves to send the below ground message to above ground. The system10may include a battery and the controller12includes a relay bank which prevents electrical feedback from the battery to the controller12.

The present invention pertains to a controller12for allowing personnel in a tunnel below ground to communicate with a location above ground. The controller12comprises an uplink interface24through which uplink messages are sent to the location above ground. The controller12comprises a downlink interface26through which downlink messages are received from above ground. The controller12comprises a personnel communication interface through which personnel messages are sent to and received from the personnel below ground in the tunnel. The controller12comprises a processing unit22which takes downlink messages received from the downlink interface26and transmits the downlink messages as personnel messages to the personnel through the personnel communication interface, and which takes personnel messages received from the personnel communication interface and transmits the personnel messages as uplink messages above ground through the uplink interface24.

The present invention pertains to a method for allowing personnel in a tunnel below ground to communicate with a location above ground. The method comprises the steps of sending uplink messages from a controller12through an uplink portion14below ground in the tunnel through earth to above ground. The controller12is in communication with the uplink portion14. There is the step of sending messages from above ground through earth to the controller12through a downlink portion16below ground in the tunnel, the controller12in communication with the downlink portion16. There is the step of sending from the controller12through a personnel communication portion18wirelessly to the personnel downlink messages as personnel messages. The controller12is in communication with the personnel communication portion18. There is the step of receiving wirelessly by the controller12from the personnel below ground in the tunnel personnel messages.

There may be the steps of a processing unit22of the controller12taking downlink messages received from the downlink portion16and transmitting the downlink messages as personnel messages to the miners, and taking personnel messages received from the personnel communication portion18and transmitting the personnel messages as uplink messages above ground through the uplink portion14. There may be the steps of the controller12providing uplink messages to the uplink portion14through an uplink interface24of the controller12, providing downlink messages received from the downlink portion16to the processing unit22through a downlink interface26of the controller12, sending personnel messages to the personnel from the processing unit22through a personnel communication interface of the controller12; and receiving personnel messages from the personnel by the processing unit22through the personnel communication portion18.

There may be the step of the processing unit22broadcasting out the downlink messages as personnel messages to all personnel through the personnel communication portion18. The personnel communication portion18may include a personnel communicator28disposed with each personnel and including the step of sending from the personnel communicators28a response to each personnel message received from the controller12back to the controller12through the personnel communication portion18. The response may be either red or green, and there may be the steps of the processing unit22counting the responses that are green which were received over a predetermined time period and sending an uplink message at a frequency which corresponds to a number of responses counted in the predetermined time that are green which were receives by the controller12. There may be the step of preventing electrical feedback from a battery to external power with a relay bank of the controller12.

Referring toFIG. 1, the controller12consists of three main communication interfaces. The first, the downlink interface26, is an RS-232 serial connection to the RX downlink equipment/antenna30. When a message is sent from the surface, it is received through the RX downlink equipment/antenna30and transmitted to a processing unit22of the controller12through this RS-232 connection. The message type transmitted is a text message. This message is then sent to the POD Communicator32(CommTrac Interface) also through an RS-232 connection. From here the message is broadcast out to all of the miners on their Miner Communicator28. Each miner will generate a response to this text message (green or red) that will be received through the POD Communicator32and sent back to the through the RS-232 connection. The processing unit22will then accumulate the number of green responses over a 2 minute period. It will then turn-on and control the frequency generator34which generates a frequency that will be received on the surface (uplink). The processing unit22will set the digital outputs that correspond to one of the twenty desired frequencies. Each frequency corresponds to the number of green responses. For example, 0-3 green responses are 1 frequency and 4-6 green responses are a second frequency.

The green and red response is utilized for a yes/no to answer a question sent to a miner. For example, the message “Are you hurt?” might be sent to the miner from the surface. When received by the miner he will either press green for yes or red for no. These responses are sent back to the processing unit12using CommTrac. The data is then accumulated using the microcontroller and the number of yes responses is sent to the surface using a corresponding frequency. The specific frequency/tone is sent using the uplink seismic transducer36(the subwoofer).

Uplink Data is sent as a frequency or tone. This tone corresponds to some known canned data. Downlink data is sent as ASCII text. This downlink data is then converted to a CommTrac text message. Downlink text messages are converted to Miner Terminated Text Messages to be sent over the personnel communication portion18, which is preferably a CommTrac network. Miners will then respond with the Miner Terminated Text/Configuration Acknowledgement Message. These responses are the green/red responses that are accumulated in the non-transient memory36of the controller12and mapped to a frequency to be sent to the surface above ground. Commtrac, which provides communication between the miners in the tunnel and the controller12, is well known in the art and may be purchased from Strata Products Worldwide, LLC in Sandy Springs, Ga.

Other functions the controller12provides are battery monitoring40and power sense42. It is connected to the battery44and a message is sent through the CommTrac network every 30 minutes to the controller12providing battery health information. It also is constantly monitoring a switch46to determine if power is present. This allows the controller12to know when to operate.

In regard toFIG. 1, the 120 VAC mine power48is a source of electricity for the system10from the mine. Electricity is fed to a surge protector50and then to a triple redundant relay bank52of the controller12. The triple redundant relay bank52prevents electrical feedback from the batteries44to the equipment in the event that electricity from the mine is turned off or terminated, for example in a disaster event, so electrical feedback to the equipment will not cause a dangerous condition and potentially trigger an explosion in the mine.

The part numbers for the EMS system, battery, and surge protector are, respectively:

Elite Power Systems EMS-4-V2

Elite Power Systems GBS-LEMP100AH

Electricity from the triple redundant relay bank52is then fed to a battery charger54, and from the battery charger54fed to a battery energy management system56. The battery energy management system56monitors and controls electricity to the batteries44and protects the batteries44. The battery energy management system56will turn off electricity to the batteries44in the event that electricity is too low or too high, either of which could result in damage to the batteries44. The battery energy management system56basically load balances the battery discharge and the charging of the batteries44. Electricity from the battery energy management system56is provided to the batteries44, here, preferably 12 V 100 aH lithium ion batteries44. The batteries44are connected to the external power switch46which turns on and off the system10.

The batteries44are electrically connected to two seismic amplifiers58which are in turn connected to a seismic transducer36to produce a vibrating signal that is transmitted to the surface for communication with the surface. Also connected to the seismic amplifiers58is the frequency generator34that receives input from the digital control outputs60of the controller12and controls the vibration signal that is ultimately transmitted by the seismic transducer36. See U.S. Pat. No. 7,843,768, incorporated by reference herein, for details of the operation of the transmission signal to the surface from the system10.

The controller12also has a power sense42connected to the electrical power switch46to determine when the system10is activated. The controller12also has battery monitoring40connected to the batteries44to monitor the charge of the batteries44. The batteries44are also connected to a 12 volt regulator62of the controller12. The 12 volt regulator62is electrically connected to the frequency generator34and to a POD communicator32and to a downlink receiver64to power them. The POD communicator32in turn is connected to a DC block66, which in turn is connected to the Commtrac antenna68in a first explosion proof enclosure70to power the Commtrac antenna68. In addition, a first RSS 232 level shifter72is in communication with the POD communicator32through which messages are sent to and received from the Commtrac antenna68in regard to communication with the miners. It should be noted that Commtrac is an example of a mesh network generally that can be used with the present invention.

A second RS-232 level shifter74of the controller12is in communication with the Ultra Receive Antenna30in a second explosion proof enclosure76through which messages are received from the surface. The downlink portion where signals are transmitted from the surface to the Ultra Receive antenna30and the Ultra Receive board64was purchased from Ultra Electronics Maritime Systems, Inc. in Nova Scotia, Canada.

Each explosion proof container is attached to the controller12through an MSHA approved cable. This cabling is required by MSHA for intrinsic safety reasons and is well known in the art.

As mentioned above, CommTrac is a well-known standalone communications and tracking system that operates by having nodes that are positioned ideally on the ceiling of a mine. These nodes form a self-healing wireless network that is used as a backbone for transmitting data to the surface. Data is received by each node and is transmitted to the next “hop” or node until it reaches the surface. The nodes are organized in a tree structure so each node knows exactly what node it must send data to in order for it to reach the surface. Each node positioned on the ceiling will send a status update once every 5 minutes to report battery life and the state of the network as that node sees it. The miners carry personal devices, otherwise called here personnel communicators28that transmit their location once per second by receiving the signal strength of all the nodes around them. This data is sent to the surface where their position is determined by having the server run an algorithm. The server can determine the location because it knows the geographical location of every node in the network. The miner's personal communicator28can also send text messages through this network as well as receive them.

When the system10is activated by the switch46, then the node having the controller12turns into the Gateway of the CommTrac network or the root of the tree. This root is normally on the surface, but since that communication is assumed to be cut-off, the node with the controller12will become this Gateway. All data will flow to the controller12of the system10, but it will essentially only care about responses to the questions asked from the surface. When a message is sent from the surface, it is sent through the downlink portion16of the system10to the controller12, and then out the CommTrac network and downstream through the network until it reaches all of the miners. This is when each miner will respond with the 1, 2, or 3 colors. These messages are received by the Gateway and passed to the controller12just as they would in a surface server. But now the controller12filters for the responses and accumulates them. Once all of the responses are received, a frequency/tone that corresponds to a number of responses is sent to the surface by the controller12.

Before the switch46is thrown, the CommTrac node that would become the Gateway is only used to relay data to the surface Gateway and operates like any other node of the CommTrac network. It will not pass any data it receives to the controller12in the system10. After the switch46is thrown, this node becomes the Gateway (endpoint for the data) so the CommTrac network will reconfigure itself to relay all data to the new Gateway. Once the CommTrac node that has now become the gateway in the system10receives any data, it will be passed to the controller12in the system10. When the switch46is thrown, the controller12will re-program the CommTrac node parameters to tell it to become a gateway for the CommTrac network.

The switch46may be a lever physically located on the explosion proof enclosure20, also called the Through the Earth (TTE) box. Until that switch46is thrown, the CommTrac node used in the system10just acts like any other node in the CommTrac network. Once the switch46is activated, then this node converts itself to a CommTrac gateway that causes the other underground nodes to reconfigure to send data to it. By the switch46being thrown indicates the CommTrac underground network has lost communication with the surface or doesn't exist. Miners would typically only want to use the system10if they had too because CommTrac communication had been destroyed.

In reconfiguration, the following occurs. The nodes are always searching for a parent to connect to and send data. This parent is decided by selecting the least number of hops to the root of the tree (the Gateway). Once the node with the controller12becomes the root/Gateway, all of the nodes will automatically reconfigure to send data to it because it will now be broadcasting in its beacon that it has the least number of hops.