Abstract:
Open-chamber smoke detector and detection method. An elecromagnetic emitter emits radiation, a sensor receives the signal after it has travelled through the monitored area and analyses it to determine whether smoke is present by comparison with a reference signal representative of a smoke plume. An alarm condition is signaled when an evolution in the obtained data corresponds to the reference profile within a threshold amount.

Description:
BACKGROUND 
       [0001]    Smoke detectors, such as commercial smoke detectors, use infrared light scattering or ionization-based techniques inside a small plastic and metallic chamber with inlets of controlled dimensions to prevent entry of unwanted particles. However, some unwanted airborne particles do make their way into the chamber, causing false alarms. Over time, these particles may also collect at the inlets of the sensor chamber, making it more difficult for smoke particles to diffuse into the chamber. 
         [0002]    Smoke detectors are subject to a minimum threshold level of cleanliness. Below this level, maintenance is required. Such maintenance may be mandated by code, regulations, or standards, such as those provided by the National Fire Protection Association (NFPA). Another issue with existing commercial smoke detectors is the time to detection. For smoke detection to occur, the smoke particles have to travel to the detector from the source and enter the sensor chamber. The amount of time this takes is dictated by a variety of factors, such as the flow dynamics of the particles, the fire energy, and the size of the room being monitored. 
       BRIEF SUMMARY 
       [0003]    In one embodiment, a method for monitoring an area includes receiving, by at least one sensor, a first plurality of signals and processing the first plurality of signals to obtain data. The obtained data is compared to a profile corresponding to an evolution of a smoke plume. Based on the comparison, an alarm condition is signaled when an evolution in the obtained data corresponds to the profile within a threshold amount. 
         [0004]    Additionally or alternatively, in this or other embodiments a second plurality of signals is emitted by the at least one sensor. The processing of the first plurality of signals is based on the emitted second plurality of signals. 
         [0005]    Additionally or alternatively, in this or other embodiments the second plurality of signals includes infrared (IR) light. 
         [0006]    Additionally or alternatively, in this or other embodiments the second plurality of signals includes electromagnetic (EM) fields. 
         [0007]    Additionally or alternatively, in this or other embodiments the EM fields are non-optical fields. 
         [0008]    Additionally or alternatively, in this or other embodiments the first plurality of signals is based on a temperature of one or more entities located in the area. 
         [0009]    Additionally or alternatively, in this or other embodiments the at least one sensor does not include a chamber. 
         [0010]    Additionally or alternatively, in this or other embodiments a component of the at least one sensor is tuned to discriminate between the smoke plume and an object. 
         [0011]    In another embodiment, an apparatus includes memory having instructions stored thereon that, when executed, cause the apparatus to receive a first plurality of signals, process the first plurality of signals to obtain data, compare the obtained data to a profile corresponding to an evolution of a smoke plume, and based on the comparison, signal an alarm condition when an evolution in the obtained data corresponds to the profile within a threshold amount. 
         [0012]    Additionally or alternatively, in this or other embodiments the instructions, when executed, cause the apparatus to emit a second plurality of signals. The processing of the first plurality of signals is based on the emitted second plurality of signals. 
         [0013]    Additionally or alternatively, in this or other embodiments the apparatus includes at least one light emitting diode (LED) configured to emit second plurality of signals as infrared (IR) light, and wherein the apparatus includes at least one photodiode configured to receive the first plurality of signals. 
         [0014]    Additionally or alternatively, in this or other embodiments the second plurality of signals includes electromagnetic (EM) fields. 
         [0015]    Additionally or alternatively, in this or other embodiments the EM fields adhere to Wi-Fi® standards. 
         [0016]    Additionally or alternatively, in this or other embodiments the first plurality of signals is based on a temperature of the smoke plume. 
         [0017]    Additionally or alternatively, in this or other embodiments the instructions are executed by at least one logic device. 
         [0018]    Additionally or alternatively, in this or other embodiments the instructions are executed by a plurality of logic devices arranged as a pipeline. 
         [0019]    Additional embodiments are described below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The present disclosure is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements. 
           [0021]      FIG. 1  is a diagram illustrating an exemplary system for detecting smoke via the use of infrared light and time of flight data; 
           [0022]      FIG. 2  is a diagram illustrating an exemplary system for detecting smoke via the use of infrared light and time of flight data; 
           [0023]      FIG. 3  is a diagram illustrating an exemplary system for detecting smoke via the use of an electromagnetic field; 
           [0024]      FIG. 4  is a diagram illustrating an exemplary system for detecting smoke via the use of a pyrometer sensor; 
           [0025]      FIG. 5  illustrates a flow chart of an exemplary method; and 
           [0026]      FIG. 6  illustrates an exemplary system for detecting smoke. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    It is noted that various connections are set forth between elements in the following description and in the drawings (the contents of which are included in this disclosure by way of reference). It is noted that these connections in general may be direct or indirect and that this specification is not intended to be limiting in this respect. In this respect, a coupling between entities may refer to either a direct or an indirect connection. 
         [0028]    Exemplary embodiments of apparatuses, systems, and methods are described that provide alternatives to detecting smoke based on light scattering or absorption within a physically defined chamber. Embodiments may include one or more emitters that may emit one or more signals, and one or more detectors that may be configured to detect the existence or location of smoke or smoke plumes based on the emitted signal(s). In some embodiments, the emitters and detectors may be operative based on infrared (IR) light and/or electromagnetic (EM) fields. In some embodiments, the EM fields may include non-optical fields or those fields that are outside of a range of (visible) light. 
         [0029]    In some embodiments, a sensor may monitor for changes in thermal gradients located within the sensor&#39;s range. Temperature data may be analyzed, potentially based on one or more parameters (e.g., spatial, temporal, temperature) to detect the existence or location of smoke or smoke plumes. 
         [0030]    Referring now to  FIG. 1 , a system  100  in accordance with one or more embodiments is shown. The system  100  may include one or more sensors  102 . In the embodiment shown in  FIG. 1 , the sensor  102  is mounted to a ceiling of an area that is monitored. The area may correspond to a room, such as a room on the order of a few square meters. 
         [0031]    The sensor  102  may include one or more emitters that may project beam(s) of IR light into the area. The emitters may include a light emitting diode (LED). The sensor  102  may include one or more detectors that measure and track the location of smoke or smoke plumes based on the emitted IR light. In some embodiments, the detection of smoke may be based on a time of flight of photons. The detectors may include a photodiode to convert received light into a current or voltage. 
         [0032]    In some embodiments, the emitter(s) and/or detector(s) may be fixed in terms of their configuration. For example, the emitters may be configured to emit light at a fixed angle. The detectors may be configured to receive light (e.g., scattered light), potentially as a function of the emitted light, at a fixed angle or position. 
         [0033]    The detectors may be configured to detect scattered light as a function of color, wavelength, or frequency. For example, the detector may be tuned in accordance with a wavelength and frequency, such that smoke may be detected. The tuning may be used to provide an ability to distinguish smoke from other entities or objects, such as bugs and other ubiquitous particles. The tuning may be a function of the wavelength of IR light projected by the emitter(s). Accordingly, a multi-wavelength analysis algorithm may be provided in some embodiments. 
         [0034]    In some embodiments, the sensor  102  may include electronic or software filters that may discriminate between ambient light modulation and real smoke-induced signals. The filtration may reject signals caused by ambient light and may allow signals caused by smoke scattering or obscuration to pass. Measured signals may be conditioned and processed, at which point an alarm condition may be signaled if the measured or detected smoke exceeds a threshold. 
         [0035]    Referring to  FIG. 2 , a system  200  in accordance with one or more embodiments is shown. The system  200  may include one or more sensors  202 . In the embodiment shown in  FIG. 2 , the sensor  202  is mounted to a wall of an area (e.g., a room) that is monitored. The sensor  202  may perform functions similar to those described above with respect to the sensor  102 , and may include components or devices similar to those described with respect to the sensor  102 . Accordingly, a complete (re)description of the sensor  202  is omitted for the sake of brevity. 
         [0036]    Referring to  FIG. 3 , a system  300  in accordance with one or more embodiments is shown. The system  300  may include one or more sensors  302 . In the embodiment shown in  FIG. 3 , the sensor  302  is mounted to a ceiling of an area (e.g., a room) that is monitored. 
         [0037]    The sensor  302  may use projected EM fields to extend the sensing range beyond that of a traditional smoke chamber. The projected EM field may register disturbances due to sufficiently dense smoke plumes in motion that enter the EM field&#39;s sensitivity region. Based on advances in low-power Wi-Fi® technology for motion detection at longer ranges (even behind walls), Wi-Fi® technology may also be used for the detection of dense plumes in motion at reduced ranges. While the embodiment described herein utilizes Wi-Fi® technology, it is to be appreciated that the use of Blue-Tooth® or other wireless communication technologies are contemplated within the scope of the present disclosure. 
         [0038]    One or multiple EM emitters may project into a confined area or space. Smoke plumes in motion may be detected by one or multiple EM detectors in conjunction with the emitter(s). The emitter(s) and/or the detector(s) may be included in the sensor  302 . 
         [0039]    The sensor  302  may include electronic or software filters and algorithms which enable the sensor  302  to discriminate between solid objects (e.g., bugs) and real smoke plume-induced signals. Measured signals may be conditioned and processed, at which point an alarm condition may be signaled if the measured or detected smoke exceeds a threshold. 
         [0040]    In an embodiment, the sensor  302  includes two emitters and one detector. During a calibration task or background task, the two emitters may emit EM fields that interfere with one another such that a reference signal level in the detector is established. In some embodiments, the reference signal level may be selected such that it corresponds to a zero or null value. Next, when objects or smoke plumes are present in the area being monitored, the signal(s) detected by the detector may be different from the reference signal level. In this manner, a comparison may be made between the reference signal level and subsequent detected signals to determine whether a smoke plume is present. This arrangement does not require a direct line of sight between emitter and receiver, which may be located within the same housing. 
         [0041]    Referring to  FIG. 4 , a system  400  in accordance with one or more embodiments is shown. The system  400  may include one or more sensors  402 . In the embodiment shown in  FIG. 4 , the sensor  402  is mounted to a ceiling of an area (e.g., a room) that is monitored. 
         [0042]    The sensor  402  may include a multi-element pyrometer to detect characteristic spatial, temporal, and temperature signatures of smoke plumes. A detection range may extend beyond that of a traditional smoke point detector. A single sensor  402  may monitor an area or space for changes in the thermal gradients within the sensor  402 &#39;s range. 
         [0043]    An algorithm may be executed by the sensor  402  to analyze temperature data over time to determine if the data is indicative of a smoke plume. The number of elements or pixels included in the pyrometer may be selected so as compare detected data to smoke plume profiles or characteristics. The algorithm may discriminate various observed signal responses from the sensor  402  (such as smoke plumes, people, dust plumes, etc.) by comparing characteristics of smoke plumes with those of nuisance sources. Measured signals may be conditioned and processed, at which point an alarm condition may be signaled if the measured or detected smoke exceeds a threshold. 
         [0044]    Turning now to  FIG. 5 , a flow chart of a method  500  is shown. The method  500  may be operative in connection with one or more environments, systems, devices, or components, such as those described herein. The method  500  may be used to determine the existence or likelihood of the existence of smoke or fire in an area that is actively being monitored, such as a room on the order of a few square meters. 
         [0045]    In block  502 , one or more signals may be emitted. For example, the emitted signals may take the form of IR light or EM fields. As part of block  502 , the area may be characterized, potentially as part of a background or calibration task. 
         [0046]    In block  504 , one or more signals may be received. The received signals may be based on the signal(s) emitted in block  502 . The received signals may be based on, or include, IR light or EM fields. The received signals may be based on a temperature associated with an entity, such as an object or smoke plume. 
         [0047]    In block  506 , the received signals of block  504  may be processed to obtain data. The processing may include applying a filter or filtering algorithm to the signals or data. 
         [0048]    In block  508 , the data may be examined to see if, over time, the data aligns with a characteristic profile of how smoke or a smoke plume tends to expand or evolve. If the data aligns with a smoke or smoke plume profile within a threshold amount, an alarm condition may be signaled or provided. A location of smoke in terms of a distance and an angle relative to a reference direction may be provided as part of block  508 . 
         [0049]    In some embodiments, one or more of the blocks or operations (or a portion thereof) of the method  500  may be optional. In some embodiments, the blocks may execute in an order or sequence different from what is shown in  FIG. 5 . In some embodiments, one or more additional blocks or operations not shown may be included. 
         [0050]    Turning now to  FIG. 6 , a system  600  in accordance with one or more embodiments is shown. The system  600  may be associated with a detector, such as a smoke detector. 
         [0051]    The system  600  is shown as including a memory  602 . The memory  602  may store executable instructions. The executable instructions may be stored or organized in any manner and at any level of abstraction, such as in connection with one or more applications, processes, routines, methods, etc. As an example, at least a portion of the instructions are shown in  FIG. 6  as being associated with a first program  604   a  and a second program  604   b.    
         [0052]    The instructions stored in the memory  602  may be executed by one or more logic devices  606 , e.g., a processor, a programmable logic device (PLD) a field programmable gate array (FPGA), etc. 
         [0053]    In terms of the use of the logic devices  606 , in some embodiments the logic devices  606  may be organized or arranged as a pipeline. For example, in some instances it may be desirable to have an overall time resolution of 1 nanosecond, corresponding to a frequency of 1 GHz. In order to use a low-cost FPGA with a time resolution of 8 nanoseconds, eight such samplers of an FPGA may be arranged in a pipeline, where each sampler may perform a portion (e.g., one-eighth) of the overall work. The metrics provided are illustrative, and any time resolution or number of devices or FPGAs may be used in a given embodiment. 
         [0054]    The logic device  606  may be coupled to one or more input/output (I/O) devices  608 . In some embodiments, the I/O device(s)  608  may include one or more of a keyboard or keypad, a touchscreen or touch panel, a display device, a microphone, a speaker, a mouse, a button, a remote control, a joystick, a printer, a communications transmitter/receiver, a fire panel, etc. The I/O device(s)  608  may be configured to provide an interface to allow a user to interact with the system  600 . 
         [0055]    The memory  602  may store data  616 . The data  616  may be based on an emission or reception of one or more signals. For example, the system  600  may include an emitter or transmission unit (TU)  624  that may emit or transmit one or more signals and a reception unit (RU)  632  that may receive one or more signals. The data  616  may be indicative of an environment in which the system  600  is located. The data  616  may be processed by the logic device  606  to determine the existence or location of smoke within an area being monitored by the system  600 . 
         [0056]    The system  600  is illustrative. In some embodiments, one or more of the entities may be optional. In some embodiments, additional entities not shown may be included. For example, in some embodiments the system  600  may be associated with one or more networks. In some embodiments, the entities may be arranged or organized in a manner different from what is shown in  FIG. 6 . 
         [0057]    Embodiments of the disclosure may actively monitor an area. For example, rather than waiting for smoke to reach the proximity of a detector unit or smoke chamber as in conventional systems, aspects of the disclosure may provide for a detector unit that proactively attempts to determine whether smoke is present in an area being monitored by sending light into a protected area. Thus, a time needed to detect the presence of smoke can be reduced, as the impact of smoke transport dynamics on time to alarm are reduced. Furthermore, enhanced accuracy may be obtained in terms of determining a location of a smoke plume within an area that is being monitored. 
         [0058]    In accordance with embodiments of the disclosure, a sensor or detector unit might not include a chamber, thereby reducing maintenance and installation costs. 
         [0059]    As described herein, in some embodiments various functions or acts may take place at a given location and/or in connection with the operation of one or more apparatuses, systems, or devices. For example, in some embodiments, a portion of a given function or act may be performed at a first device or location, and the remainder of the function or act may be performed at one or more additional devices or locations. 
         [0060]    Embodiments may be implemented using one or more technologies. In some embodiments, an apparatus or system may include one or more processors and memory storing instructions that, when executed by the one or more processors, cause the apparatus or system to perform one or more methodological acts as described herein. Various mechanical components known to those of skill in the art may be used in some embodiments. 
         [0061]    Embodiments may be implemented as one or more apparatuses, systems, and/or methods. In some embodiments, instructions may be stored on one or more computer-readable media, such as a transitory and/or non-transitory computer-readable medium. The instructions, when executed, may cause an entity (e.g., an apparatus or system) to perform one or more methodological acts as described herein. Aspects of the disclosure have been described in terms of illustrative embodiments thereof. Numerous other embodiments, modifications and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure. For example, one of ordinary skill in the art will appreciate that the steps described in conjunction with the illustrative figures may be performed in other than the recited order, and that one or more steps illustrated may be optional.