Patent Application
20080258963
The present invention relates to a low-cost, extremely-intuitive visual aide for fire fighters and the like. More particularly, the invention relates to the use of a fixed directional antenna at the safe exit point and a compass aided direction estimator adapted to receive a signal from the directional antenna and guide the user to the safe exit.
There are a number of devices currently available for firefighters, first responders and others entering a facility when it is in need of an emergency response such as from a fire, explosion, leaking gas or other hazardous materials. The devices include global positioning units, radio and RF communication components and other sophisticated technology. However, there remains a need to provide a low-cost, extremely-intuitive visual aide for such personnel to direct themselves toward a safe exit point in a building during an emergency.
The goal of any such device would be to get the personnel to a safe exit when there is no time for sophisticated technology to function. One such device adds to the traditional use of fire alarms to alert building occupants to a fire. A fire alarm alone is not designed to guide people out of a fire.
One product that modifies the fire alarm system is sold by Honeywell International Inc. under the trade name ExitPoint™ which uses directional sound technology to mark paths to safety. Varying tones and intensities from the devices, which are placed along escape routes, help lead occupants toward exits. Directional sound clearly communicates the location of exits using broadband noise. Exitpoint™ incorporates four different field selectable sound pulse patterns. The patterns consist of broadband noise, which makes it possible to locate where the sound is coming from. The four pulse patterns are used to create a pathway out of the building and mark its perimeter exits. The sound pattern becomes faster as the building occupant approaches the perimeter exit. Additional tone pulses can be added to the patterns to alert occupants that they are approaching a stairway and need to proceed either up or down.
There is still a need for a simple, economic device and method that would lead or guide persons at risk in a facility to a safe exit so that each person so under peril would have his or her own directions to the safe exit.
It would be of advantage in the art if a unit could be carried by a firefighter, first responder and the like that would point to a safe exit based on information carrying signals that can be simply and reliably converted into exit directions.
Yet another advantage would be if a device and method could be provided that would display an indication of the direction a user should take to a safe exit.
It would be another advance in the art if a device and method could be provided that would adjust or compensate for signals that are reflected, to further aid the user to move to a safe exit.
Other advantages will appear hereinafter.
It has now been discovered that the above and other advantages of the present invention may be obtained in the following manner. Specifically, the present invention provides a direction finding device for finding the direction to an exit for a person in a facility. The invention includes one or more safe exits in a facility having a source transmitting an electromagnetic beam having direction information with respect to a compass direction. A receiver unit carried by a person in the facility receives the beam from the source and determines the direction of arrival of the beam with respect to the compass direction. In the display a direction is shown for the person to move toward the exit, such as by illuminating an arrow pointing to the safe exit.
The beam containing the direction information may be any electro-magnetic wave or beam, and preferably is selected from the group consisting of an RF beam, an ultrasound beam and combinations there of.
The source beam may be an omni-directional beam and the receiver unit may use an antenna array for selectively receiving the omni-directional beam to determine the angle at which the beam is received. Alternatively the source can be an antenna array sending a plurality of beams, each of which contains specific information of its direction with respect to the compass direction and the receiver includes a single antenna to determine which of the plurality of beams is the received beam.
When the source is an antenna array and the receiver unit includes an antenna array for selectively receiving the beam, the means for determining the direction of the received beam is used to determine a direction corrected for any difference between the information direction and the received direction.
For a more complete understanding of the invention, reference is hereby made to the drawings, wherein like numbers refer to like elements, and in which:
The invention is directly related to providing directions for exit in times of emergency or danger in the facility, such as from fire, smoke, pollution, and other events which are unsafe. Firefighters, first responders, emergency medical technicians and the like may enter a facility during an emergency and when that emergency escalates, those personnel need to evacuate as quickly as possible, even under circumstances of significantly reduced vision. Specifically the user is provided with direction information that identifies the coordinates of the beam with respect to north and east, for example, and the display of the direction is also shown in relation to the same coordinates.
As shown in
As seen in
Even if the person 17 turns left or right, or rotates, the arrow in display 27 will continue to point to exit 13 in response to signal 15, because the signal 15 and the arrow in display 27 are both identified by coordinates that are based on the compass direction.
Signal 15 may be generated by transmitter 11 in several ways. The transmitter may employ an omni-directional antenna to transmit beacons, in all 360°, and the antenna 21 of receiver 19 may be an antenna array adapted to receive many signals and identify the one signal that comes directly into the antenna array. This embodiment may lose some accuracy when the signal 15 is not in direct line of sight from the transmitter 11 to the receiver 19, but, rather, has bounced off walls or other objects.
Alternatively, transmitter 11 may use directional antennas at exit 13 to transmit one beacon at a time with the appropriate direction information for that direction. Antenna 21 of receiver 19 could then be an omni-directional antenna so the controller used the data in signal 15 to determine the direction for display 27 to show. However, this embodiment does not provide for the person 17 to verify that the signal with the highest RSSI value is the direct LOS signal. In
In a preferred embodiment, both the transmitter 11 and antenna 21 are antenna arrays and send receive a plurality of beacons, each with the correct coordinates with respect to the compass. Controller 21 is programmed to compare the angle of arrival with the advertised angle in the data in signal 15b. If they are the same angle, person 17 knows that display 27 is indicating a direct path to exit 13. If they are not the same, person 17 therefore knows that the angle is a reflected signal and the controller 21, with or without indicating to person 17 that it has done so, will display a direction based on the adjustment to the compass coordinates for the signal. Person 17 goes in the direction of receipt until receiver 19 has received a direct line of sight signal.
While particular embodiments of the present invention have been illustrated and described, it is not intended to limit the invention, except as defined by the following claims.
