Patent Publication Number: US-11657692-B1

Title: Smoke detector

Description:
TECHNICAL FIELD 
     The present disclosure relates to a smoke detector, and methods of operating a smoke detector. 
     BACKGROUND 
     Smoke detectors can be implemented in indoor environments (e.g., buildings) or outdoor environments to detect smoke. For instance, a smoke detector can be mounted at a point in a room of a building to detect smoke in the room. Smoke detection can minimize risk by alerting users and/or components of a fire control system of a fire event occurring in the environment. 
     A Light Detection and Ranging (LiDAR) smoke detector is an example of a smoke detector. A LiDAR smoke detector can utilize optical systems, such as laser beam emitters and light receivers, to detect smoke in an environment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a top view of an area that includes a smoke detector in accordance with one or more embodiments of the present disclosure. 
         FIG.  2    is a top view of an area that includes a smoke detector in accordance with one or more embodiments of the present disclosure. 
         FIG.  3    is a block diagram of a smoke detector in accordance with one or more embodiments of the present disclosure. 
         FIG.  4    is an example method of operating a smoke detector in accordance with one or more embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     A smoke detector, and methods of operating a smoke detector, are described herein. In some examples, one or more embodiments include a laser emitter configured to emit a laser beam that illuminates an object in an area, a light receiver configured to receive light reflected from the illuminated object, and a controller configured to determine, based on the light reflected from the illuminated object, an amount of space in the area that is blocked from a field of view of the smoke detector by the object, and provide an indication responsive to the determined amount of space being above a threshold amount of space. 
     Smoke detectors may use laser beam emitters in conjunction with light receivers to detect smoke. For example, a smoke detector may use Light Detection and Ranging (LiDAR) technology to detect smoke. For instance, when a laser beam is emitted in an indoor environment, it may encounter a substance or material and light may be reflected and/or scattered to the light receiver. If no substance or material is present in the path of the laser, the light will instead reflect and/or scatter off a wall of the indoor environment and back to the light receiver. The smoke detector can determine the difference between a received light signal that has been reflected and/or scattered off a wall or light reflected off another substance or material, because the intensity of the received light signal will be considerably greater if it has been reflected and/or scattered off a wall as opposed to reflecting and/or scattering off a substance such as smoke. Additionally, a light signal that has passed through smoke will be slightly attenuated. 
     As such, by rotating a laser beam emitter and light receiver of a smoke detector and emitting pulses of light from the laser beam emitter, an indoor environment can be scanned to detect smoke. For example, the smoke detector may be positioned in a corner of an area (e.g., a room) and rotated from zero to ninety degrees to scan the entire room for smoke. By recording the alignment, position, and orientation of the smoke detection system at the time that the smoke is detected, the approximate location of the smoke in the room can also be determined. 
     In some instances, however, the indoor environment (e.g., room) may include additional fixed features (e.g., objects), such as, for instance, pillars, lighting features (e.g., fixtures), signs, and/or ladders, among others, that may also reflect and/or scatter the light from the emitted laser beam. Such objects may act to partially obstruct (e.g., block) the field of view of the smoke detector, and thus may prevent the detector from being able to detect smoke in the space (e.g., portion) of the room blocked by the object. Depending on the size of the object blocking the detector, and/or the position of the object in the room relative to the detector, the amount of space in the room in which smoke would be unable to be detected by the detector may exceed the amount allowed by the smoke detector operational requirements and/or fire codes of the local jurisdiction. 
     A smoke detector in accordance with the present disclosure, however, can identify such obstructions, and determine whether such obstructions would result in a violation of the applicable smoke detector operational requirements and/or fire codes. As such, during commissioning (e.g., installation) of the smoke detector, the installer can quickly determine whether the installation of the detector is successful, or whether the detector needs to be moved to a different location in the room. Further, after the smoke detector has been successfully commissioned and is in operation, the detector can continue to identify the presence of any newly introduced obstructions, determine whether they would result in a violation, and provide an indication (e.g., notification) of any violation to the building supervisor or other appropriate party. 
     Further, in order for a rotating smoke detector (e.g., a smoke detector with a rotating laser beam emitter and light receiver) to effectively detect smoke, the laser beam needs to be maintained on the smoke for a sufficient amount of time (e.g., the dwell time) for the detector (e.g., the light receiver of the detector) to make a valid measurement. As such, the scan of the room can not be too quick. However, the full scan of the entire room needs to be completed by the detector in as short of a time as possible in order to ensure that smoke that is present in any portion of the room can be detected in a timely manner (e.g., within 60 seconds), as may be required by the smoke detector operational requirements and/or fire codes of the local jurisdiction. 
     A smoke detector in accordance with the present disclosure, however, can reduce (e.g., minimize) its total scan time, while still maintaining a sufficient dwell time, by adjusting its rotation speed based on the different portions of the room it is scanning. For example, the intensity of the light signal received by the light receiver from a smoke plume or wall of the room, and therefore the dwell time of the smoke detector, is inversely proportional to the square of the distance between the light receiver and the smoke plume or wall. As such, the smoke detector can determine which walls of the room are closer to the detector and which walls of the room are further away from the detector, and adjust its rotation speed such that its rotation speed (e.g., scan) is quicker for portions of the room in which the wall is closer to the detector and slower for portions of the room in which the wall is further away from the detector. 
     In the following detailed description, reference is made to the accompanying drawings that form a part hereof. The drawings show by way of illustration how one or more embodiments of the disclosure may be practiced. 
     These embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice one or more embodiments of this disclosure. It is to be understood that other embodiments may be utilized and that process, electrical, and/or structural changes may be made without departing from the scope of the present disclosure. 
     As will be appreciated, elements shown in the various embodiments herein can be added, exchanged, combined, and/or eliminated so as to provide a number of additional embodiments of the present disclosure. The proportion and the relative scale of the elements provided in the figures are intended to illustrate the embodiments of the present disclosure and should not be taken in a limiting sense. 
     The figures herein follow a numbering convention in which the first digit or digits correspond to the drawing figure number and the remaining digits identify an element or component in the drawing. Similar elements or components between different figures may be identified by the use of similar digits. For example,  102  may reference element “02” in  FIG.  1   , and a similar element may be referenced as  202  in  FIG.  2   . 
     As used herein, “a”, “an”, or “a number of” something can refer to one or more such things, while “a plurality of” something can refer to more than one such things. For example, “a number of components” can refer to one or more components, while “a plurality of components” can refer to more than one component. 
       FIG.  1    is a top view of an area  100  that includes a smoke detector  102  in accordance with one or more embodiments of the present disclosure. Smoke detector  102  can be, for example, a Light Detection and Ranging (LiDAR) smoke detector, as will be further described herein. Area  100  can be an area of an indoor environment. For instance, area  100  can be a room of a facility (e.g., a building). 
     Smoke detector  102  can be part of (e.g., a component of) a fire control system of the facility. As described herein, a fire control system may be any system designed to detect and/or provide a notification of fire events occurring in a facility. For example, a fire control system may include smoke detection apparatuses and/or devices (e.g., detector  102 ) that can sense a fire occurring in the facility, alarms (e.g., speakers, strobes, etc.) that can provide a notification of the fire to the occupants of the facility, fans and/or dampers that can perform smoke control operations (e.g., pressurizing, purging, exhausting, etc.) during the fire, and/or sprinklers that can provide water to extinguish the fire, among other components. A fire control system may also include a control unit such as a physical fire control panel (e.g., box) installed in the facility that can be used by a user to directly control the operation of the components of the fire control system. In some embodiments, the fire control system can include a non-physical control unit or a control unit located remotely from the facility. 
     As shown in  FIG.  1   , area  100  includes a plurality of walls: a first (e.g., north) wall  104 - 1 , a second (e.g., east) wall  104 - 2 , a third (e.g., south) wall  104 - 3 , and a fourth (e.g., west) wall  104 - 4 . It is noted that embodiments of the present disclosure are not limited to the layout or the shape of area  100  illustrated in  FIG.  1   . 
     As shown in  FIG.  1   , smoke detector  102  (e.g., a laser emitter of smoke detector  102 , as will be further described herein) can emit a beam (e.g., a laser beam)  106  across area  100 . As used herein, the terms “light” or “beam” can include any type of light beam, such as a laser. These terms can also include pulses of light. For example, beam  106  can be a pulsed laser beam (e.g., comprise a plurality of pulses). 
     Smoke detector  102  can rotate beam  106  (e.g., a rotation mechanism of smoke detector  102  can rotate the laser emitter of smoke detector  102 , as will be further described herein), such that beam  106  periodically scans across area  100  and illuminates different portions of area  100  (e.g., different portions of the walls of the room), as represented by arrow  112  illustrated in  FIG.  1   . A “scan” of the beam  106  can refer to a rotation of the beam such that the beam begins at an initial angular position and ends at a terminal angular position. As an example, a scan can include the beam moving from an angle substantially parallel to, or past substantially parallel to, wall  104 - 4  (e.g., from an angle of 90 degrees or greater than 90 degrees) to, or past, an angle substantially parallel to wall  104 - 3  (e.g., to or past an angle of 0 degrees), and a subsequent scan can include the beam moving from the angle substantially parallel to, or past substantially parallel to, wall  104 - 3  back to the angle substantially parallel to, or past substantially parallel to, wall  104 - 4 . 
     As shown in  FIG.  1   , area  100  can include an object  108 . Object  108  can be a fixed object, such as, for instance, a pillar, lighting feature (e.g., fixture), sign, or ladder, among other examples. Beam  106  can illuminate object  108 , as illustrated in  FIG.  1   . However, object  108  may partially obstruct (e.g., block) the field of view of smoke detector  102 . For instance, object  108  may prevent smoke detector  102  from being able to monitor, and detect smoke in, space  110  of area  100  illustrated in  FIG.  1   . 
     Smoke detector  102  (e.g., a light receiver of smoke detector  102 , as will be further described herein) can receive light reflected from illuminated object  108  and light reflected from the illuminated different portions (e.g., the illuminated portions of walls  104 - 1  and  104 - 2 ) of area  100  as beam  106  scans across area  100 . As used herein, the term “reflected” may be used to refer to light that is not only reflected but may be reflected and/or scattered. For example, the light may be reflected off a surface at an angle of incidence equaling the angle of reflection. Light that is incident on a surface or material can also be scattered in a multitude of directions in accordance with embodiments of the present disclosure. 
     Based on the light reflected from illuminated object  108 , smoke detector  102  (e.g., a controller of smoke detector  102 , as will be further described herein) can determine the amount (e.g., size) of space  110  that is blocked from the field of view of smoke detector  102  by object  108 . For instance, smoke detector  102  can measure and/or analyze the intensity of the light reflected from illuminated object  108  to determine the size of space  110 . Smoke detector  102  can make the determination of the size of space  110  automatically (e.g., without input from a user), or responsive to input from a user, such as the installer of smoke detector  102 . 
     For example, smoke detector  102  (e.g., the controller of smoke detector  102 ) can determine the shape (e.g., the outline shape) of area  100  based on the light (e.g., the intensity of the light) reflected from the illuminated different portions of area  100 , and the location (e.g., the radial coordinates) of object  108  in area  100  based on the light (e.g., the intensity of the light) reflected from illuminated object  108 . Smoke detector  102  can then determine (e.g., calculate) the size of space  110  based on the determined shape of area  100  and the determined location of object  108  in area  100 . Smoke detector  102  can determine the location of object  108  in area  100  based on the alignment of smoke detector  102  (e.g., the alignment of the laser emitter of the detector) when emitting the beam  106  (e.g., the laser pulse) that illuminates object  108 , and the amount of time for smoke detector  102  to receive the light reflected from illuminated object  108  (e.g., the time of flight of the laser pulse that illuminates object  108 ). 
     Smoke detector  102  (e.g., the controller of smoke detector  102 ) can determine whether the amount (e.g., size) of space  110  that is blocked from the field of view of smoke detector  102  by object  108  is above a threshold amount of space (e.g., a threshold size). The threshold amount of space can be pre-defined, or set by a user (e.g., the installer) of smoke detector  102 , and can be determined (e.g., defined or set) based on the smoke detector operational requirements and/or fire codes of the local jurisdiction of area  100 . For instance, the threshold amount of space can be the maximum amount of unmonitored space allowed in area  100  by the smoke detector operational requirements and/or fire codes of the local jurisdiction. 
     Smoke detector  102  (e.g., the controller of smoke detector  102 ) can provide an indication (e.g., trigger an alert and/or fault condition) responsive to determining the size of space  110  is above the threshold amount of space. For example, smoke detector  102  can provide the indication to an additional device, such as, for instance, a mobile device or other computing device of the installer and/or a supervisor of the facility, via a text message or the internet or other network associated with the fire control system of area  100 . In some embodiments, smoke detector  102  can also provide (e.g., to the additional device) a different indication, such as, for instance, an authorization and/or approval, responsive to determining the size of space  110  is not above the threshold amount of space. 
     Although not shown in  FIG.  1    for simplicity and so as not to obscure embodiments of the present disclosure, in some instances area  100  may include an additional object that may block the field of view of smoke detector  102 . For instance, the additional object may be a new object that is introduced to area  100  after smoke detector  102  has been commissioned and/or installed. In such an instance, beam  106  can illuminate the additional object, and smoke detector  102  can receive the light reflected from the illuminated additional object, determine the amount of space in area  100  that is blocked from its field of view by the additional object based on the reflected light, and provide an indication responsive to the determined amount of space being above the threshold amount of space, in a manner analogous to that described for object  108 . 
       FIG.  2    is a top view of an area  200  that includes a smoke detector  202  in accordance with one or more embodiments of the present disclosure. Smoke detector  202  and area  200  can be, for example, analogous to smoke detector  102  and area  200 , respectively, previously described in connection with  FIG.  1   . For example, smoke detector  202  can be part of a fire control system of a facility that includes area  200 , and area  200  can include a plurality of walls  204 - 1 ,  204 - 2 ,  204 - 3 ,  204 - 4  analogous to walls  104 - 1 ,  104 - 2 ,  104 - 3 ,  104 - 4 , respectively, described in connection with  FIG.  1   . 
     Further, smoke detector  202  can emit a beam  206  across area  200 , and rotate beam  206  such that beam  206  periodically scans across area  200  and illuminates different portions of area  200 , as represented by arrow  212 , in a manner analogous to that previously described in connection with  FIG.  1   . Smoke detector  202  can receive light reflected from the illuminated different portions (e.g., the illuminated portions of walls  204 - 4 ,  204 - 1  and  204 - 2 ) of area  200  as beam  206  scans across area  200 , in a manner analogous to that previously described in connection with  FIG.  1   . 
     Based on the light reflected from the illuminated different portions of area  200 , smoke detector  202  (e.g., the controller of smoke detector  202 ) can adjust the speed at which beam  206  rotates (e.g., the speed at which the rotation mechanism of the detector rotates the laser emitter of the detector). For instance, smoke detector  202  can measure and/or analyze the intensity of the light reflected from the illuminated different portions of area  200  to determine the adjustment to the speed at which beam  206  rotates. 
     For example, smoke detector  202  (e.g., the controller of smoke detector  202 ) can determine the distance of each of the different portions of area  200  (e.g., the illuminated portions of walls  204 - 4 ,  204 - 1  and  204 - 2 ) from smoke detector  202  based on the light reflected from the illuminated different portions of area  200  (e.g., the greater the intensity of the light reflected from a portion of area  200 , the shorter the distance of that portion of area  200  from the detector), and adjust the speed at which beam  206  rotates based on these determined distances. For instance, smoke detector  202  can adjust the speed at which beam  206  rotates such that the amount of time for which beam  206  illuminates each respective different portion of area  200  is directly proportional to the determined distance of that respective portion from smoke detector  202 . As such, the rotation speed of beam  206  can be quicker through those portions of area  200  that are closer to smoke detector  202  and slower through those portions of area  200  that are further away from smoke detector  202 . 
     In such a manner (e.g., by adjusting the rotational speed of beam  206 ), smoke detector  202  can adjust the amount of time for which beam  206  illuminates (e.g., the dwell time for) each respective different portion of area  200 . For example, smoke detector  202  can adjust the rotational speed of beam  206  through the different portions of area  200  such that the beam rotates through each respective portion of area  200  at a speed sufficient (e.g., slow enough) to detect smoke in that respective portion, but also sufficient to illuminate each of the different portions of area  200  (e.g., fast enough to complete the scan of area  200 ) within a particular amount of time. The particular amount of time can be pre-defined, or set by a user (e.g., the installer) of smoke detector  202 , and can be determined (e.g., defined or set) based on the smoke detector operational requirements and/or fire codes of the local jurisdiction of area  200 . For instance, the particular amount of time can be the maximum amount of time allowed to complete the scan of area  200  by the smoke detector operational requirements and/or fire codes of the local jurisdiction. As an example, the particular amount of time can be 60 seconds. 
       FIG.  3    is a block diagram of a smoke detector  302  in accordance with one or more embodiments of the present disclosure. Smoke detector  302  can be, for example, smoke detector  102  and/or  202  previously described in connection with  FIGS.  1  and  2   , respectively. 
     As shown in  FIG.  3   , smoke detector  302  can include a laser emitter  322 . Laser emitter  322  can be any device, system, or apparatus configured to emit light, such as a laser beam. For example, laser emitter  322  can emit a laser beam that illuminates an object in an area and/or different portions of the area, as previously described herein. The light emitted can be pulses, such as pulses of lasers. In some embodiments, laser emitter  322  can be LiDAR transmitter. In some embodiments, laser emitter  322  can be a laser diode. 
     As shown in  FIG.  3   , smoke detector  302  can include a light receiver  324 . Light receiver  324  can be or include a sensor, detector, lens, or combination thereof configured to receive light and/or to convert light into a form that is readable by an instrument. For example, light receiver  324  can receive light reflected from an illuminated object in an area and/or illuminated portions of the area, as previously described herein. In some embodiments, light receiver  324  can be a LiDAR receiver or an electro-optical sensor. In some embodiments, light receiver  324  can include a clock and/or processing resources. The light receiver  324  can be configured to measure the time taken for a pulse of light to travel from laser emitter  322 , reflect and/or scatter off an object, substance, or material, and travel back to the light receiver. 
     As shown in  FIG.  3   , smoke detector  302  can include a rotation mechanism  326  that can rotate laser emitter  322 . For example, rotation mechanism  326  can rotate laser emitter  322  such that the laser beam emitted by laser emitter  322  periodically scans across an area to illuminate different portions of the area, as previously described herein. Rotation mechanism  326  can be mechanical and/or electrical. It may be configured to rotate the laser emitter  322  at a particular speed and/or over a given range. For example, if smoke detector  302  is positioned in a corner of an area (e.g., room), rotation mechanism  326  may alternately rotate laser emitter  322  from 0 degrees to 90 degrees and from 90 degrees to 0 degrees. As such, if the laser emitter  322  emits pulses periodically while being rotated by rotation mechanism  326 , smoke detector  302  can scan the entire area for smoke. In some embodiments, rotation mechanism  326  can rotates the light receiver  324  and the laser emitter  322  together. For instance, rotation mechanism  326  can be a rotary platform or table driven by a motor. 
     As shown in  FIG.  3   , smoke detector  302  can include a controller  328  having a processor  330  and a memory  332 . Memory  332  can be any type of storage medium that can be accessed by processor  330  to perform various examples of the present disclosure. For example, memory  332  can be a non-transitory computer readable medium having computer readable instructions (e.g., computer program instructions) stored thereon that are executable by processor  330  to operate smoke detector  302  in accordance with the present disclosure. That is, processor  330  can execute the executable instructions stored in memory  332  to operate smoke detector  302  in accordance with the present disclosure. 
     Memory  332  can be volatile or nonvolatile memory. Memory  332  can also be removable (e.g., portable) memory, or non-removable (e.g., internal) memory. For example, the memory can be random access memory (RAM) (e.g., dynamic random access memory (DRAM), resistive random access memory (RRAM), and/or phase change random access memory (PCRAM)), read-only memory (ROM) (e.g., electrically erasable programmable read-only memory (EEPROM) and/or compact-disk read-only memory (CD-ROM)), flash memory, a laser disk, a digital versatile disk (DVD) or other optical disk storage, and/or a magnetic medium such as magnetic cassettes, tapes, or disks, among other types of memory. Further, memory  332  can be located internal to smoke detector  302 , or located internal to another computing resource (e.g., enabling computer readable instructions to be downloaded over the Internet or another wired or wireless connection). 
       FIG.  4    is an example method  440  of operating a smoke detector in accordance with one or more embodiments of the present disclosure. The smoke detector can be, for example, smoke detector  102 ,  202 , and/or  302  previously described in connection with  FIGS.  1 ,  2 , and  3   , respectively. The method can be performed and/or executed by, for example, controller  328  previously described in connection with  FIG.  3   . 
     At block  442 , method  440  includes rotating a laser emitter of the smoke detector such that a laser beam emitted by the laser emitter illuminates an object in an area and different portions of the area. The laser emitter can be, for instance, laser emitter  322  previously described in connection with  FIG.  3   , and the laser beam emitted by the laser emitter can be, for instance, laser beam  106  and/or  206  previously described in connection with  FIGS.  1  and  2   , respectively. The laser emitter can be rotated using, for instance, rotation mechanism  326  previously described in connection with  FIG.  3   . The area can be, for instance, area  100  and/or  200  previously described in connection with  FIGS.  1  and  2   , respectively, the object can be, for instance, object  108  previously described in connection with  FIG.  1   , and the different portions of the area can comprise, for instance, different walls of the area, as previously described in connection with  FIGS.  1  and  2   . 
     At block  444 , method  440  includes determining, based on light reflected from the illuminated object, an amount of space in the area blocked from a field of view of the smoke detector by the object. The amount of space blocked from the field of view of the smoke detector can correspond to, for instance, space  110  previously described in connection with  FIG.  1   , and can be determined, for instance, based on the intensity of the light reflected from the illuminated object, as previously described in connection with  FIG.  1   . 
     At block  446 , method  440  includes providing an indication responsive to the determined amount of space being above a threshold amount of space. The threshold amount of space can be, for instance, defined or set based on the smoke detector operational requirements and/or fire codes of the local jurisdiction of the area, as previously described in connection with  FIG.  1   . The indication can be provided, for instance, to an additional device, as previously described in connection with  FIG.  1   . 
     At block  448 , method  440  includes adjusting a speed of the rotation of the laser emitter based on light reflected from the illuminated different portions of the area. For instance, the speed of the rotation of the laser emitter can be adjusted based on the intensity of the light reflected from the illuminated different portions of the area, as previously described in connection with  FIG.  2   , and can be adjusted by adjusting the speed at which the rotation mechanism of the detector rotates the laser emitter of the detector, as previously described herein. 
     Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art will appreciate that any arrangement calculated to achieve the same techniques can be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments of the disclosure. 
     It is to be understood that the above description has been made in an illustrative fashion, and not a restrictive one. Combination of the above embodiments, and other embodiments not specifically described herein will be apparent to those of skill in the art upon reviewing the above description. 
     The scope of the various embodiments of the disclosure includes any other applications in which the above structures and methods are used. Therefore, the scope of various embodiments of the disclosure should be determined with reference to the appended claims, along with the full range of equivalents to which such claims are entitled. 
     In the foregoing Detailed Description, various features are grouped together in example embodiments illustrated in the figures for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the embodiments of the disclosure require more features than are expressly recited in each claim. 
     Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.