Occupant counting device

Abstract

A sensor may be configured to determine the number of people who have entered or exited a space. The sensor may include a pyroelectric infrared (PIR) detection circuit capable of generating different output signal patterns in response to people entering or exiting the space. The sensor may determine whether a person has entered or exited the space based on the output signal pattern. The sensor may include a thermopile array, a radar detection circuit, or a visible light sensing circuit. The thermopile array, radar detection circuit, or visible light sensing circuit is capable of detecting the position and / or movement of people within an area monitored by the sensor, and determining whether a person has entered or left the space based on the detected movement. The occupant count of the space may then be determined accordingly by the sensor or by a system controller.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 722,555, filed on August 24, 2018, and U.S. Provisional Patent Application No. 62 / 783,525, filed on December 21, 2018, the disclosures of which are incorporated herein by reference in their entireties. Background Art

[0003] In order to manage a user environment, such as a residence or office building, it may be desirable to have the ability to estimate the number of people occupying the user environment at a given time. Knowing the number of people in the environment can improve occupant-driven control measures, such as energy control, air quality control, room allocation and / or scheduling, etc. Prior art occupant counting methods and devices have poor accuracy and / or high cost, and often cause privacy issues. Summary of the invention

[0004] Sensor devices for determining a count of occupants (e.g., occupant counts) in a space are described herein. The sensor devices are installed near the space to detect movement (e.g., movement of occupants) adjacent to the devices. For example, the sensor devices may be installed in doorways and / or entrances to the space to detect occupants entering and / or exiting the space.

[0005] The control circuit can maintain an occupant count for the space by increasing the count when it is determined that a person has entered the space and decreasing the count when it is determined that a person has exited the space. The sensor device may also include a communication circuit that can be used to send a signal (e.g., a digital message) indicating the occupant count. The signal can be sent to a system controller or another device with similar occupant counting capabilities. The sensor device may reset the occupant count to zero after sending the signal, for example, to prevent the propagation of any erroneous counts. The system controller may be configured to receive occupant count data (e.g., entry / exit count data) from the sensor device and maintain an occupant count for the space. For example, the system controller may be configured to receive occupant count data from multiple sensor devices and maintain a total occupant count for the space.

[0006] The system controller may also be configured to obtain information about the occupancy status of the space from the occupancy sensor. The system controller may compare the occupant count reported by the sensor device with the occupancy status indicated by the occupancy sensor and resolve any mismatches between the two pieces of information. For example, if the occupant count reported by the sensor device is greater than zero, but the occupancy sensor indicates that the space is not occupied, the system controller may reset the occupant count to zero.

[0007] The sensor device may include a detection circuit (such as a pyroelectric infrared (PIR) detection circuit) and a control circuit. The PIR detection circuit may include a plurality of PIR elements connected in an anti-series configuration. The PIR elements may respond to the movement of a person in a detection area, and the PIR detection circuit may generate an output signal having different patterns corresponding to different directions of movement. The control circuit may collect a plurality of samples from the output of the PIR detection circuit in response to the detected movement of the person. From the plurality of samples, the control circuit may identify a first sample and a second sample having opposite polarities and amplitudes above a certain threshold. Based on the patterns exhibited by the plurality of samples, such as the order in which the first sample signal and the second sample signal are generated, the control circuit may determine whether the person has entered the space or has exited the space.

[0008] The sensor device may include a thermopile array (e.g., a plurality of thermosensitive elements arranged in an N×N array). The thermosensitive element may respond to thermal energy in a two-dimensional region and may generate a signal representing a thermal map or a two-dimensional (2D) thermal image of the region. The control circuit may receive a signal from the thermopile array, determine the position of the energy emitting object in the 2D region by processing the signal, and further determine the movement of the energy emitting object through multiple zones of the region. Based on these movements, the control circuit may determine whether the energy emitting object has entered the space or has left the region. The sensor device may include a radar sensing circuit, a visible light sensing circuit, and / or a time-of-flight sensing circuit (e.g., instead of or in addition to a thermopile array). The radar sensing circuit, the visible light sensing circuit, and / or the time-of-flight sensing circuit may function in a manner similar to a thermopile array, at least in terms of having the ability to determine the position and / or movement of an object in an area monitored by the radar sensing circuit, the visible light sensing circuit, or the time-of-flight sensing circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a simplified diagram of an exemplary load control system including one or more occupant counting devices and occupancy sensors.

[0010] Figure 2 is a perspective view of an exemplary occupant counting sensor as described herein.

[0011] Figure 3A is a block diagram of an example occupant counting sensor as described herein.

[0012] Figure 3B Exemplary waveforms of output signals of an exemplary occupant counting sensor are shown as people enter and exit a space monitored by the occupant counting sensor.

[0013] Figure 4 is a flow chart of an exemplary occupant counting procedure.

[0014] Figure 5 is an example diagram illustrating an occupant counting sensor configured to detect occupants in a space based on the movement of the occupants in a two-dimensional area.

[0015] Figure 6 Yes Figure 5 Block diagram of an exemplary occupant counting sensor described in .

[0016] Fig. 7A is an example state diagram for determining the movement of an occupant when the occupant enters a space.

[0017] Figure 7B is an example state diagram for determining the movement of an occupant when the occupant leaves a space.

[0018] Figure 8 is a communication sequence diagram depicting an exemplary message flow in a system including two occupant counting sensors and a system controller.

[0019] Fig. 9 is a flow chart of an example procedure for resetting an occupancy counting sensor.

[0020] Fig.10 is a flow chart of an exemplary occupant counting reception procedure.

[0021] Fig.11 is an exemplary block diagram of a system controller configured to receive occupant counting information transmitted by an occupant counting sensor. DETAILED DESCRIPTION

[0022] Figure 1 1 is a simplified diagram of an exemplary load control system 100 for controlling the amount of power delivered to one or more electrical loads from an alternating current (AC) power source (not shown). The load control system 100 may be installed in a room 102 of a building. The load control system 100 may include a plurality of control devices configured to communicate with each other via wireless signals (e.g., radio frequency (RF) signals 108). Alternatively or additionally, the load control system 100 may include a wired digital communication link coupled to one or more of the control devices to provide communication between the load control devices. The control devices of the load control system 100 may include a plurality of control source devices (e.g., input devices operable to send digital messages in response to user input, occupancy / vacancy conditions, changes in measured light intensity, etc.) and a plurality of control target devices (e.g., load control devices operable to receive digital messages and control corresponding electrical loads in response to the received digital messages). A single control device of the load control system 100 may operate as both a control source device and a control target device.

[0023] The control source device may be configured to send a digital message directly to the control target device. In addition, the load control system 100 may include a system controller 110 (e.g., a central processor or a load controller) operable to communicate digital messages to and from control devices (e.g., the control source device and / or the control target device). For example, the system controller 110 may be configured to receive a digital message from the control source device and, in response to the digital message received from the control source device, send a digital message to the control target device. The control source device and the control target device and the system controller 110 may be configured to communicate using a proprietary RF protocol (e.g., Protocol) to send and receive RF signals 108. Other RF protocols may also be used to send the RF signal 108, such as a standard protocol (e.g., one of WIFI, ZIGBEE, Z-WAVE, KNX-RF, ENOCEAN RADIO protocols), or a different proprietary protocol.

[0024] The load control system 100 may include one or more load control devices, such as a dimmer switch 120 for controlling a lighting load 122. The dimmer switch 120 may be adapted to be wall mounted in a standard electrical wall box. The dimmer switch 120 may include a countertop or plug-in load control device. The dimmer switch 120 may include a toggle actuator (e.g., a push button) and an intensity adjustment actuator (e.g., a rocker switch). Actuation (e.g., continuous actuation) of the toggle actuator may toggle (e.g., turn off and on) the lighting load 122. Actuation of the upper or lower portion of the intensity adjustment actuator may increase or decrease the amount of power delivered to the lighting load 122, respectively, and thus increase or decrease the intensity of the receiving lighting load within a range of minimum intensity (e.g., about 1%) to maximum intensity (e.g., about 100%). The dimmer switch 120 may include a plurality of visual indicators (e.g., light emitting diodes (LEDs)) that may be arranged in a linear array and illuminated to provide feedback of the intensity of the lighting load 122. Examples of wall-mounted dimmer switches are described in more detail in U.S. Patent No. 5,248,919, entitled “LIGHTING CONTROLDEVICE,” issued on September 28, 1993, and U.S. Patent No. 9,676,696, entitled “WIRELESS LOAD CONTROL DEVICE,” issued on June 13, 2017, the entire disclosures of which are incorporated herein by reference.

[0025] The dimmer switch 120 may be configured to wirelessly receive digital messages (e.g., from the system controller 110) via the RF signal 108, and control the lighting load 122 in response to the received digital messages. Examples of dimmer switches operable to send and receive digital messages are described in greater detail in commonly assigned U.S. Patent Application Publication No. 2009 / 0206983, entitled “COMMUNICATION PROTOCOL FOR RADIOR-FREQUENCY LOAD CONTROL SYSTEM,” published on August 20, 2009, the entire disclosure of which is incorporated herein by reference.

[0026] The load control system 100 may include one or more remotely located load control devices, such as a light emitting diode (LED) driver 130 for driving an LED light source 132 (e.g., an LED light engine). For example, the LED driver 130 may be remotely located in or adjacent to a lighting fixture of the LED light source 132. The LED driver 130 may be configured to receive a digital message via the RF signal 108 (e.g., from the system controller 110) and control the LED light source 132 in response to the received digital message. The LED driver 130 may be configured to adjust the color temperature of the LED light source 132 in response to the received digital message. An example of an LED driver configured to control the color temperature of an LED light source is described in more detail in commonly assigned U.S. Patent No. 9,538,603, entitled “SYSTEMS AND METHODS FOR CONTROLLING COLOR TEMPERATURE,” issued on January 3, 2017, the entire disclosure of which is incorporated herein by reference. The load control system 100 may also include other types of remotely located load control devices, such as electronic dimming ballasts for driving fluorescent lamps.

[0027] The load control system 100 may include one or more daylight control devices, such as motorized window treatments 150 (such as motorized cellular shades) for controlling the amount of daylight entering the room 102. Each motorized window treatment 150 may include a window treatment fabric 152 suspended from a head rail 154 in front of a corresponding window 104. Each motorized window treatment 150 may also include a motor drive unit (not shown) located inside the head rail 154 for raising and lowering the window treatment fabric 152 to control the amount of daylight entering the room 102. The motor drive units of the motorized window treatments 150 may be configured to receive digital messages via the RF signal 108 (e.g., from the system controller 110) and adjust the position of the corresponding window treatment fabric 152 in response to the received digital messages. The load control system 100 may include other types of daylight control devices, such as cellular shades, curtains, Roman shades, Venetian shades, Persian shades, pleated shades, tensioned roller blind systems, electrochromic or smart windows, and / or other suitable daylight control devices. Examples of battery-powered motorized window treatments are described in more detail in U.S. Patent No. 8,950,461, entitled “MOTORIZED WINDOW TREATMENT,” issued on February 10, 2015, and U.S. Patent No. 9,488,000, entitled “INTEGRATED ACCESSIBLE BATTERY COMPARTMENT FOR MOTORIZED WINDOW TREATMENT,” issued on November 8, 2016, the entire disclosures of which are incorporated herein by reference.

[0028] The load control system 100 may include one or more temperature control devices, such as a thermostat 160 for controlling the room temperature in the room 102. The thermostat 160 may be coupled to a heating, ventilation, and air conditioning (HVAC) system 162 via a control link (e.g., an analog control link or a wired digital communication link). The thermostat 160 may be configured to wirelessly communicate digital messages with a controller of the HVAC system 162. The thermostat 160 may include a temperature sensor for measuring the room temperature of the room 102, and may control the HVAC system 162 to adjust the temperature in the room to a set point temperature. The load control system 100 may include one or more wireless temperature sensors (not shown) located in the room 102 for measuring the room temperature. The HVAC system 162 may be configured to turn on and off a compressor for cooling the room 102 and turn on and off a heat source for heating the room in response to a control signal received from the thermostat 160. The HVAC system 162 may be configured to turn on and off a fan of the HVAC system in response to a control signal received from the thermostat 160. Thermostat 160 and / or HVAC system 162 may be configured to control one or more controllable dampers to control airflow in room 102. Thermostat 160 may be configured to receive digital messages via RF signal 108 (e.g., from system controller 110) and adjust heating, ventilation, and cooling in response to the received digital messages.

[0029] The load control system 100 may include one or more other types of load control devices, such as: a screw-in lamp including a dimmer circuit and an incandescent or halogen lamp; a screw-in lamp including a ballast and a compact fluorescent lamp; a screw-in lamp including an LED driver and an LED light source; an electronic switch, a controllable circuit breaker, or other switching device for turning an appliance on and off; a plug-in load control device, a controllable electrical outlet, or a controllable power strip for controlling one or more plug-in loads; a motor control unit for controlling a motor load such as a ceiling fan or exhaust fan; a drive unit for controlling an electric window treatment or projection screen; an electric interior interior or exterior blinds; thermostats for heating and / or cooling systems; temperature controls for controlling the set temperature of HVAC systems; air conditioners; compressors; electric baseboard heater controllers; controllable dampers; variable air volume controllers; fresh air intake controllers; ventilation controllers; hydraulic valves for radiators and radiant heating systems; humidity control units; humidifiers; dehumidifiers; water heaters; boiler controllers; swimming pool pumps; refrigerators; freezers; television or computer monitors; video cameras; audio systems or amplifiers; elevators; power supplies; generators; chargers such as electric vehicle chargers; and alternative energy controllers.

[0030] The load control system 100 may include one or more input devices, such as a remote control 170, an occupancy sensor 180, or an occupant counting device (e.g., an occupant counting sensor 190). The input device may be a fixed or movable input device. The system controller 110 may be configured to send one or more digital messages to a load control device (e.g., a dimmer switch 120, an LED driver 130, an electric window treatment 150, and / or a thermostat 160) in response to a digital message received from the remote control 170, the occupancy sensor 180, and / or the occupant counting sensor 190. The remote control 170, the occupancy sensor 180, and / or the occupant counting sensor 190 may be configured to send a digital message directly to the system controller 110, the dimmer switch 120, the LED driver 130, the electric window treatment 150, and / or the thermostat 160.

[0031] Remote control 170 may be configured to send digital messages to system controller 110 (eg, directly to the system controller) via RF signal 108 in response to actuation of one or more buttons of the remote control. For example, remote control 170 may be battery powered.

[0032] The occupancy sensor 180 may be configured to detect occupancy and vacancy conditions in the room 102. The occupancy sensor 180 may be an infrared sensor (e.g., a passive infrared sensor). The occupancy sensor 180 may be removably mounted to a ceiling or a wall. Figure 1 Only one occupancy sensor is shown in the figure, but those skilled in the art will recognize that the load control system 100 may include more than one occupancy sensor spaced apart for detecting occupancy conditions in different areas of the room 102. The occupancy sensor 180 may include an internal detector, such as a pyroelectric infrared (PIR) detector, an ultrasonic detector, a microwave detector, or any combination thereof. For example, the internal PIR detector may be housed in a housing that includes a lens (e.g., an outward dome-shaped lens) disposed in a front surface of the housing. The internal PIR detector is operable to receive energy (e.g., infrared energy) emitted from an occupant in the space via the lens, thereby sensing an occupancy condition in the space. The occupancy sensor 180 is operable to process the output of the PIR detector to determine whether an occupied condition or a vacant condition is currently occurring in the room 102, for example by comparing the output of the internal detector with a predetermined occupancy voltage threshold.

[0033] The occupancy sensor 180 may send a digital message to the system controller 110 via the RF signal 108 (e.g., using a proprietary protocol described herein) in response to detecting an occupied or vacant condition. The system controller 110 may be configured to send commands to corresponding load control devices to turn on or off corresponding lighting loads (e.g., lighting loads 122 and / or LED light sources 132) in response to receiving an occupied command or a vacant command, respectively. The system controller 110 may be configured to adjust the occupant count submitted by the occupant count sensor 190 (e.g., correct its accuracy) based on the occupied or vacant condition detected by the occupancy sensor 180 (e.g., as described in more detail below). Examples of RF load control systems with occupancy and vacancy sensors are described in more detail in the following patents: U.S. Pat. No. 8,009,042, entitled “RADIO-FREQUENCY LIGHTING CONTROL SYSTEM WITH OCCUPANCY SENSING,” issued on September 3, 2008 and August 30, 2011, jointly assigned; U.S. Pat. No. 8,199,010, entitled “METHOD AND APPARATUS FOR CONFIGURING AWIRELESS SENSOR,” issued on June 12, 2012; and U.S. Pat. No. 8,228,184, entitled “BATTERY-POWERED OCCUPANCY SENSOR,” issued on July 24, 2012, the entire disclosures of which are incorporated herein by reference.

[0034] The occupancy sensor 180 may additionally or alternatively include visible light sensing circuitry, such as a camera and / or image processing circuitry. The camera may be pointed into the room 102 and may be configured to record images of the room 102. The occupancy sensor 180 may be configured to detect occupancy conditions and vacancy conditions using the recorded images of the images. Examples of sensors including visible light sensing circuitry are described in more detail in commonly assigned U.S. Patent Application Publication No. 2017 / 0171941, published on June 15, 2017, and U.S. Patent Application Publication No. 2018 / 0168019, published on June 14, 2018 (both of which are titled "LOAD CONTROL SYSTEM HAVING A VISIBLE LIGHT SENSOR"), the entire disclosures of which are incorporated herein by reference.

[0035] The load control system 100 may include other types of input devices, such as temperature sensors, humidity sensors, radiometers, cloud sensors, shadow sensors, pressure sensors, smoke detectors, carbon monoxide detectors, carbon dioxide detectors, air quality sensors, motion sensors, security sensors, proximity sensors, fixture sensors, partition sensors, keypads, multi-zone control units, slider control units, kinetic or solar powered remote controls, key fobs, cell phones, smart phones, tablet computers, personal digital assistants, personal computers, laptop computers, clocks, audio-visual control devices, security devices, power monitoring devices (e.g., power meters, energy meters, utility sub-meters, utility rate meters, etc.), central control transmitters, residential, commercial or industrial controllers, and / or any combination thereof.

[0036] The system controller 110 can be coupled to a network, such as a wireless or wired local area network (LAN), for example, for access to the Internet. The system controller 110 can be wirelessly connected to the network, for example, using Wi-Fi technology. The system controller 110 can be coupled to the network via a network communication bus (e.g., an Ethernet communication link). The system controller 110 can be configured to communicate with one or more network devices (e.g., a mobile device 140, such as a personal computing device and / or a wearable wireless device) via the network. The mobile device 140 can be located on an occupant 142 (e.g., can be attached to the occupant's body or clothing or can be held by the occupant). The mobile device 140 can be characterized by a unique identifier (e.g., a serial number or address stored in a memory) that uniquely identifies the mobile device 140 and thereby identifies the occupant 142. Examples of personal computing devices can include smart phones (e.g., Smartphone, Smartphone or smartphones), laptops and / or tablet devices (e.g. Handheld computing devices). Examples of wearable wireless devices may include activity tracking devices such as Devices, device, and / or Sony devices), smart watches, smart clothing (e.g. Smart wear, etc.), and / or smart glasses (such as Google In addition, the system controller 110 may be configured to communicate with one or more other control systems (eg, a building management system, a security system, etc.) via a network.

[0037] The mobile device 140 may be configured to send digital messages to the system controller 110, for example, in one or more Internet Protocol packets. For example, the mobile device 140 may be configured to send digital messages to the system controller 110 via a LAN and / or via the Internet. The mobile device 140 may be configured to send digital messages to an external service (e.g., If ThisThen That The mobile device 140 may transmit and receive the RF signal 109 via a Wi-Fi communication link, a Wi-MAX communication link, a Bluetooth communication link, a near field communication (NFC) link, a cellular communication link, a TV white space (TVWS) communication link, or any combination thereof. Alternatively or additionally, the mobile device 190 may be configured to transmit the RF signal according to a proprietary protocol. The load control system 100 may include other types of network devices coupled to the network, such as a desktop personal computer, a television supporting Wi-Fi or wireless communication, or any other suitable device supporting the Internet protocol. Examples of load control systems operable to communicate with mobile and / or network devices on the network are described in more detail in commonly assigned U.S. Patent Application Publication No. 2013 / 0030589, entitled “LOAD CONTROL DEVICE HAVING INTERNET CONNECTIVITY,” published on January 31, 2013, the entire disclosure of which is incorporated herein by reference.

[0038] The system controller 110 may be configured to determine the location of the mobile device 140 and / or the occupant 142. The system controller 110 may be configured to control (e.g., automatically control) the load control device (e.g., dimmer switch 120, LED driver 130, electric window treatment 150, and / or temperature control device 160) in response to determining the location of the mobile device 140 and / or the occupant 142. One or more of the control devices of the load control system 100 may transmit a beacon signal, for example, an RF beacon signal transmitted using a short-range and / or low-power RF technology (such as Bluetooth technology). The load control system 100 may also include at least one beacon transmitting device 144 for transmitting the beacon signal. The mobile device 140 may be configured to receive the beacon signal when it is located near the control device that is currently transmitting the beacon signal. The beacon signal may include a unique identifier that identifies the location of the load control device that transmitted the beacon signal. Since the beacon signal may be transmitted using a short-range and / or low-power technology, the unique identifier may indicate the approximate location of the mobile device 140. The mobile device 140 may be configured to send a unique identifier to the system controller 110, and the system controller 110 may be configured to use the unique identifier (e.g., using data stored in a memory or retrieved via the Internet) to determine the location of the mobile device 140. Examples of load control systems for controlling one or more electrical loads responsive to the location of a mobile device and / or an occupant within a building are described in more detail in commonly assigned U.S. Patent Application Publication No. 2016 / 0056629, published on February 25, 2016, and entitled “LOAD CONTROL SYSTEM RESPONSIVE TO LOCATION OF AN OCCUPANT AND MOBILE DEVICES,” the entire disclosure of which is incorporated herein by reference.

[0039] The operation of the load control system 100 may be programmed and configured using, for example, the mobile device 140 or other network device (e.g., when the mobile device is a personal computing device). The mobile device 140 may execute a graphical user interface (GUI) configuration software for allowing a user to program how the load control system 100 will operate. For example, the configuration software may be run as a PC application or a Web interface. The configuration software and / or the system controller 110 (e.g., via instructions from the configuration software) may generate a load control database that defines the operation of the load control system 100. For example, the load control database may include information about the operational settings of different load control devices (e.g., dimmer switches 120, LED drivers 130, electric window treatments 150, and / or thermostats 160) of the load control system. The load control database may include information about associations between load control devices and input devices (e.g., remote controls 170, occupancy sensors 180, occupancy counting sensors 190, etc.). The load control database may include information about how the load control device responds to inputs received from the input devices. Examples of configuration programs for load control systems are described in more detail in the following patents: commonly assigned U.S. Patent No. 7,391,297, entitled "HANDHELD PROGRAMMER FOR A LIGHTING CONTROL SYSTEM," issued on June 24, 2008; U.S. Patent Application Publication No. 2008 / 0092075, entitled "METHOD OF BUILDING A DATABASE OF A LIGHTING CONTROL SYSTEM," published on April 17, 2008; and U.S. Patent Application Publication No. 2014 / 0265568, entitled "COMMISSIONING LOAD CONTROL SYSTEMS," published on September 18, 2014, the entire contents of which are incorporated herein by reference.

[0040] The occupant counting sensor 190 may be capable of detecting when a person enters or exits the room 102. The occupant counting sensor 190 may include multiple PIR elements (e.g., two PIR detectors). These elements may include pyroelectric materials that are sensitive to heat (e.g., infrared radiation). The elements may be arranged in an anti-series connection so that the responses (e.g., output voltages) of the individual PIR elements to a heat source (e.g., a person entering or exiting the room 102) are opposite in polarity, for example, to eliminate parasitic noise. In addition, the anti-series connection enables identification of which individual PIR element first responds (e.g., first detects a change in infrared energy). These characteristics of the PIR elements may be used to determine the direction of motion associated with a person, and thereby determine whether the person has entered or exited the room 102. For example, when a person enters the room 102, his / her movement may be detected as motion in one direction. When a person exits the room, his / her motion may be determined to be in the opposite direction. Based on the motion (and the resulting entry / exit status of a person), the occupant count sensor 190 may be configured to determine an occupant count and / or a change in occupant count for the room 102 by incrementing the occupant count when a person enters the room and decrementing the occupant count when a person leaves the room.

[0041] The occupant counting sensor 190 may be mounted and oriented to detect energy (e.g., IR energy) emitters moving through a doorway. Figure 1 As shown in FIG. 1 , the occupant counting sensor 190 can be mounted on a corner (e.g., an upper corner) of a doorway 106 leading to the room 102, but other mounting locations are possible. For example, the occupant counting sensor 190 can be mounted on a lower corner of the doorway 106, on the middle side of the doorway, on the left or right side of the doorway, and / or on the inside or outside of the doorway. In addition, the occupant counting sensor 190 can be mounted to a doorframe around the door, inside a doorframe, and / or otherwise mounted to a structure around the door to appropriately detect occupants moving through the doorway 106. In addition, multiple occupant counting sensors can be mounted to various locations of the doorway 106 to improve the accuracy of detecting people entering or exiting the room 102.

[0042] The occupant counting sensor 190 may include a focusing device, such as a lens (e.g., a Fresnel lens), which may be configured to focus IR energy from an occupant onto the PIR elements. The lens may be used for a variety of purposes, including, for example, to enhance the accuracy of motion detection and / or extend the detection range of the occupant counting sensor 190. For example, a Fresnel lens may capture more IR radiation and focus it onto a small spot (e.g., at the PIR elements inside the occupant counting sensor 190), thereby extending the detection range of the occupant counting sensor 190. As the IR source moves, the focal point may move across the PIR elements of the occupant counting sensor 190, and a group of PIR elements of the occupant counting sensor 190 may be exposed to the focal point at one time, thereby triggering the generation of a patterned output signal as described herein.

[0043] like Figure 1 , a first PIR element of the PIR elements of the occupant counting sensor 190 may detect movement in a first area 192, and a second PIR element of the PIR elements may detect movement in a second area 194. For example, the occupant counting sensor 190 may be positioned and / or oriented such that when an occupant enters and / or exits the room 102 through the doorway 106, the first area 192 and the second area 194 pass through the chest of the occupant. When the occupant moves into the room, the first PIR element of the PIR elements may detect movement in the first area 192 before the second PIR element of the PIR elements detects movement in the second area 194. The output signal generated by the PIR element may indicate movement in a particular direction. For example, if the output includes a positive peak followed by a negative peak, the occupant counting sensor 190 may determine that a person has entered the room 102. If the output includes a negative peak followed by a positive peak, the occupant counting sensor 190 may determine that a person has left the room 102. It should be noted that the corresponding pattern corresponding to the entry / exit determination may vary based on the mounting orientation of the occupant counting sensor.

[0044] The occupant counting sensor 190 may include a switch (not shown) that may be manipulated to inform the occupant counting sensor 190 about the orientation of the installation (e.g., whether the occupant counting sensor is installed to the left or right side of the doorway 106 and / or the inside or outside of the doorway). Based on the orientation, the occupant counting sensor 190 may know which particular output signal pattern corresponds to which direction of movement. For example, when the occupant counting sensor 190 is installed in a first orientation, the sensor may associate a positive-negative peak signal pattern with a person entering the room 102. When the occupant counting sensor 190 is installed in a second orientation, the sensor may associate a positive-negative peak signal pattern with a person leaving the room 102.

[0045] The occupant counting sensor 190 may include other types of detection circuitry. For example, the occupant counting sensor 190 may include a thermopile array (such as an N×N array of thermally responsive elements) configured to generate a two-dimensional thermal image of the coverage area of ​​the room 102. The occupant counting sensor 190 may include a radar sensing device that utilizes a transmitting antenna array (e.g., a phased array) and / or a receiving antenna array (e.g., a phased array) to record a radar image of the entry location. The occupant counting sensor 190 may include a visible light sensing device that utilizes a camera pointed at the entry location of the room 102 to record an image of the entry location. The occupant counting sensor 190 may include time-of-flight sensing circuitry capable of providing a three-dimensional image of an area of ​​the room 102. The images generated by these detection circuits may be processed to determine the location and / or movement of occupants in the area of ​​the room 102 in order to determine whether the occupants have entered or exited the room 102. For example, using a heat map (e.g., a 2D thermal image) generated by the thermopile array, the control circuitry of the occupant counting sensor 190 can track the movement of an occupant through multiple zones of the coverage area (e.g., near a doorway) so that the control circuitry can determine, based on the pattern and / or direction of movement, whether the occupant is entering or leaving the room 102. Examples of image-based detection circuitry are described in more detail below.

[0046] In response to determining an occupant count for the room 102 or detecting a change in the occupant count, the occupant count sensor 190 may send one or more digital messages to the system controller 110 via the RF signal 108 (e.g., using a proprietary protocol described herein). The digital message may indicate an occupant count or a change therein. For example, the occupant count sensor 190 may be a one-way transmitter (e.g., may not be configured to receive digital messages) and may be configured to send (e.g., periodically send) a sensor occupant count indicating a change in the occupant count since the last transmission of the occupant count sensor 190. The occupant count sensor 190 may be configured to reset the occupant count stored in a memory at the occupant count sensor after the occupant count sensor sends a change in the occupant count. For example, the sensor occupant count may be positive or negative based on how many occupants have entered or exited the room 102 since the last reset of the occupant count. The system controller 110 may be configured to maintain an occupant count for the room 102 (e.g., a room occupant count). For example, each time the system controller 110 receives a sensor occupant count from an occupant count sensor 190, the system controller 110 may add the sensor occupant count (eg, indicating a change in the occupant count detected by that particular occupant count sensor) to the room occupant count.

[0047] Based on the room occupant count, the system controller 110 can also be configured to determine the occupancy status and / or vacancy status of the room. For example, when the room occupant count is greater than zero, the system controller 110 can determine that the room 102 is occupied, and when the room occupant count reaches zero, the system controller 110 can determine that the room 102 is vacant.

[0048] The system controller 110 may be configured to process the digital message and take various actions based on the digital message and / or other information collected from the load control system 100. For example, the system controller 110 may determine, based on the digital message, a mismatch between a room occupant count determined from a sensor occupant count received in the digital message and an occupancy condition reported by the occupancy sensor 180. For example, an exemplary mismatch may occur when a room occupant count for room 102 determined by the system controller 110 is greater than zero while the occupancy sensor 180 indicates that the room is not occupied. The system controller 110 may be configured to resolve such a mismatch, for example, by resetting the room occupant count maintained by the system controller to zero. Additionally, if the system controller 110 determines, based on the digital messages sent by the first occupant count sensor and the second occupant count sensor, that the occupant count is less than zero, the system controller 110 may reset the occupant count for room 102 to zero.

[0049] The system controller 110 may be configured to collect and / or store room occupant count data over time (e.g., for multiple time periods) and thereby maintain a history (e.g., a historical view) of the occupancy state and / or occupant count of the room. The history may include multiple data points, each corresponding to a room occupant during a particular time period. The system controller 110 may also be configured to correct the history of the occupancy state and / or occupant count of the room 102 in response to resolving a mismatch between the room occupant count determined from the sensor occupant count received from the digital message and the occupancy condition reported by the occupancy sensor 180. For example, if the room occupant count of the room 102 determined by the system controller 110 is greater than zero, and the occupancy sensor 180 indicates that the room is unoccupied, the system controller 110 may reset the room occupant count to zero and update the history of the occupancy state and / or occupant count of the room (e.g., reset one or more data points in the history corresponding to the room occupant count during various time periods to zero).

[0050] In an example, the system controller 110 may be configured to receive occupant counting information from more than one occupant counting sensor associated with the room. For example, in addition to the occupant counting sensor 190, Figure 1The load control system 100 in FIG. 1 may also include one or more additional occupant counting sensors installed adjacent to one or more other doorways of the room 102. These additional occupant counting sensors may be configured to function similarly to the occupant counting sensor 190 and may provide additional information for determining the number of occupants in the room 102. For example, a first occupant counting sensor may be installed near the entrance to the room 102 and a second occupant counting sensor may be installed near the exit of the room. Both sensors are capable of determining the number of people passing through the corresponding doorway during a period of time and reporting the information to the system controller 110.

[0051] The system controller 110 may be configured to receive messages sent by the first occupant count sensor and the second occupant count sensor and aggregate the occupant counts (or changes thereto) indicated in those messages. For example, if the first occupant count sensor indicates that three people entered the room 102 during the time period, and the second occupant count sensor indicates that two people left the room 102 during the same time period, the system controller 110 may determine that the number of people occupying the room 102 is one.

[0052] As described above, the system controller 110 is able to resolve mismatches between information reported by the occupant counting sensors and information collected from other devices in the load control system 100. Using the example provided above, if the system controller 110 determines that there is an occupant in the room 102 based on the digital messages sent by the first occupant counting sensor and the second occupant counting sensor, and determines from the occupancy sensor 180 that the room is unoccupied, the system controller 110 can reset the occupant count for the room 102 to zero.

[0053] The occupant counting sensor 190 may be a two-way wireless device and may be configured to, for example, send and receive digital messages to and from the system controller 110. The occupant counting sensor 190 may be configured to maintain a room occupant count (e.g., in addition to or in lieu of determining a sensor occupant count). For example, the occupant counting sensor 190 may be configured to periodically send a room occupant count (e.g., which indicates to the system controller 110 the number of occupants currently in the room). When the occupant counting sensor 190 is configured to maintain a room occupant count, the system controller may resolve mismatches between information reported by the occupant counting sensor and information collected from other devices in the load control system 100. For example, if the system controller 110 determines that there is an occupant in the room 102, and determines from the occupancy sensor 180 that the room is unoccupied, the system controller 110 may send a digital message to the occupant counting sensor 190 to reset the occupant count of the room 102 to zero.

[0054] The occupant counting sensor 190 may be configured to perform some or all of the functions of the system controller 110. For example, the occupant counting sensor 190 may be capable of receiving information (e.g., digital messages) regarding the occupant count (or changes thereto) or occupancy status of the room 102 from other occupant counting sensors and / or from the occupancy sensor 180. The occupant counting sensor 190 may be configured to process the received information in conjunction with the occupant count determined by the occupant counting sensor 190 itself, and derive a cumulative count of the number of occupants in the room 102. Similar to the system controller 110, the occupant counting sensor 190 may be capable of resolving mismatches between various information received or derived by the occupant counting sensor 190.

[0055] Figure 2 is an exemplary occupant counting sensor 200 (e.g., Figure 1 200). The occupant counting sensor 200 may include a housing 202 for housing circuitry of the occupant counting sensor. The circuitry of the occupant counting sensor 200 may include a plurality of PIR elements (e.g., two PIR elements) that are capable of detecting energy (e.g., IR energy) from energy emitters (e.g., occupants) in a space. The PIR elements may be arranged and / or oriented to detect movement of energy emitters in front of the occupant counting sensor 200 (e.g., to detect a person entering or exiting a room).

[0056] The occupant counting sensor 200 may include a focusing device (such as a Fresnel lens 204) configured to capture energy from an energy emitter moving in front of the lens and focus the captured radiation to a small spot at the PIR element, thereby enhancing the detection range and / or accuracy of the occupant counting sensor 200. The occupant counting sensor 200 may be adjacent to a user space (e.g., Figure 1 2 . For example, the occupant counting sensor 200 may be installed at a corner (e.g., an upper corner) of the doorway and oriented to face the opposite corner of the doorway. The orientation of the occupant counting sensor 200 may be indicated (e.g., signaled), for example, via an orientation actuator 206 of the occupant counting sensor. For example, setting the orientation actuator 206 to a first position may indicate to the occupant counting sensor 200 that the Fresnel lens 204 is installed at the upper left corner of the doorway (e.g., on the inside of the doorway) and pointing in a lower right direction, while setting the orientation actuator 206 to a second position may indicate to the occupant counting sensor 200 that the Fresnel lens 204 is installed at the upper right corner of the doorway (e.g., on the inside of the doorway) and pointing in a lower left direction.

[0057] Figure 3Ais an exemplary occupant counting sensor 300 (e.g., Figure 1 Occupant counting sensor 190 and / or Figure 2 1 and 1 . The occupant counting sensor 200 of FIG. 1 is an exemplary block diagram of an occupant counting sensor 200 of FIG. 1 . The occupant counting sensor 200 may include a detection circuit 310 configured to detect an occupant in a space (e.g., an occupant entering and / or exiting the space). For example, the detection circuit 310 may include a pyroelectric infrared (PIR) detector circuit 312 and an amplifier circuit 314. The PIR detection circuit 312 may include a plurality of PIR elements (e.g., two PIR elements) that are capable of detecting energy (e.g., IR energy) from an energy emitter (e.g., an occupant) in the space and generating a PIR voltage V PIR The occupant counting sensor 300 may include a focusing device (e.g., Figure 2 The focusing device is configured to capture energy of an energy emitter moving in front of the lens and focus the captured radiation onto a PIR element of the PIR detector circuit 312. The amplifier circuit 314 can be coupled to the output of the PIR detector circuit 312 to receive the PIR voltage V PIR The amplifier circuit 314 may be configured to generate a detection voltage V DETECT , the detection voltage can indicate movement of an energy emitter through a doorway (e.g., to detect occupants entering or exiting a room).

[0058] The occupant counting sensor 300 may include a control circuit 315 configured to receive a detection voltage V from the detection circuit 310. DETECT , for detecting occupants entering and exiting the room. The control circuit 315 may include, for example, a microprocessor, a programmable logic device (PLD), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or any suitable processing device. The control circuit 315 may be configured to detect the detection voltage V generated by the detector circuit 310 based on the detection voltage V DETECT To determine occupant counts of people who have entered or exited a room.

[0059] Each PIR element of the PIR detector circuit 312 may be a pyroelectric element that may generate a voltage change across the PIR element in response to temperature changes and / or other environmental changes. The PIR elements of the PIR detector circuit 312 may be arranged in an anti-series connection such that voltage changes across each of the PIR elements due to vibration, temperature changes, and / or other environmental changes will cancel each other out and will not affect the PIR voltage V at the output of the PIR detector circuit 312. PIRDue to the anti-series connection of the PIR elements, the PIR detector circuit 312 can generate responses (e.g., peaks and / or pulses) of opposite polarity when each of the individual PIR elements is exposed to IR energy. This makes it possible to identify which individual PIR element first detected motion (e.g., a change in infrared energy). The characteristics of the PIR elements of the PIR detector circuit 312 can be used to determine the direction of movement of an occupant in front of the occupant counting sensor 300, and thereby determine whether the occupant has entered or exited the room. For example, if the detection voltage V generated by the detection circuit 310 is DETECT If the detection voltage V generated by the detection circuit 310 is positive, followed by a negative polarity, the control circuit 315 can determine that the occupant has passed through the doorway (e.g., entered the room) in the first direction. DETECT comprising a first peak amplitude of negative polarity followed by a second peak amplitude of positive polarity, the control circuit 315 can determine that the occupant has passed through the doorway in the second direction (e.g., exited the room).

[0060] Figure 3B shows the detection voltage V generated by the detection circuit 310 DETECT The amplifier circuit 314 can add a DC offset to the PIR voltage V PIR , so that the detection voltage V DETECT Centered around a midpoint voltage, such as the supply voltage V CC Half (for example, V cc / 2), such as Figure 3A . When one of the PIR elements of the PIR detector circuit 312 is exposed to a change in IR energy, followed by another one of the PIR elements being exposed to a change in IR energy, the detection circuit 310 may generate a signal (e.g., an entry signal or an exit signal). For example, when an IR radiator moves across the occupant counting sensor, a first one of the PIR elements may be exposed to a change in IR energy caused by the movement of the radiator, and then a second one of the PIR elements may be exposed to a change in IR energy. Thus, the output of the PIR detection circuit may exhibit a particular pattern corresponding to the movement of the radiator.

[0061] like Figure 3B As shown in FIG. 1 , a first signal (eg, an entry signal) may be generated when an occupant enters a space monitored by the occupant counting sensor 300. Such a first signal may be generated at a first time point t 1a The maximum peak (eg, positive peak) amplitude V is reached at (eg, when the first PIR element in the PIR elements is exposed to IR energy). MAX1 , then at the second time point t 2aThe minimum peak (eg, negative peak) amplitude V is reached at (eg, when a second PIR element in the PIR elements is exposed to IR energy). MIN1 The same characteristic of the PIR element may result in the generation of a second signal (e.g., an exit signal) when an occupant leaves the space monitored by the occupant counting sensor. Figure 3B As shown in FIG. , the second signal may be at a first time point t 1b t t t t t t t t t t t t t t t t t t t t t t t t t t t t t t 2b A maximum peak (eg, positive peak) amplitude is reached at (eg, when a first one of the PIR elements is exposed to IR energy).

[0062] A specific signal (e.g., a signal pattern) that may be generated by the detector circuit 310 corresponding to an occupant entering or exiting a room (e.g., a detection voltage V DETECT The order of the maximum and minimum peaks of the signal (e.g., the order of the maximum and minimum peaks of the signal) may depend on the orientation of the occupant counting sensor 300. For example, if the occupant counting sensor 300 is positioned adjacent to the upper right corner of a doorway inside a room, a signal (e.g., an entry signal) having a maximum peak (e.g., a positive peak) followed by a minimum peak (e.g., a negative peak) may indicate that an occupant is entering the room, while a signal (e.g., an entry signal) having a minimum peak followed by a maximum peak may indicate that an occupant is exiting the room. If the occupant counting sensor 300 is positioned adjacent to the upper left corner of a doorway inside a room, a signal (e.g., an entry signal) having a minimum peak followed by a maximum peak may indicate that an occupant is entering the room, while a signal (e.g., an entry signal) having a minimum peak followed by a maximum peak may indicate that an occupant is exiting the room.

[0063] The occupant counting sensor 300 may include an actuator that may be responsive to an orientation actuator (e.g., Figure 2 314 can obtain information about the installation orientation of the occupant counting sensor 300 via the orientation switch 316. For example, the orientation switch 316 can be set in response to actuation of the orientation actuator during configuration of the occupant counting sensor 300. For example, the control circuit 315 can be configured to map different output signal patterns of the PIR detector circuit 310 to a determination of an occupant entering or exiting a room. As explained herein, the detection voltage V DETECT Such a signal pattern may include a positive peak followed by a negative peak or a negative peak followed by a positive peak.

[0064] The control circuit 315 can maintain (eg, determine and / or update) an occupant count of the room. In response to detecting motion, the control circuit 315 can obtain a detection voltage V received from the detection circuit 310. DETECT The control circuit 315 may further infer that the room is occupied if the occupant count is greater than zero. When the occupant count drops to zero, the control circuit 315 may further infer that the room has become unoccupied.

[0065] The control circuit 315 may be configured to store the occupant count and / or occupancy status in a memory 318 of the occupant counting sensor 300. The memory 318 may be implemented as an external integrated circuit (IC) coupled to the control circuit 315 or as an internal circuit of the control circuit 315. The control circuit 315 may be configured to save different occupant counts associated with different time periods in the memory 318 so that a historical view of the occupancy status of the room (e.g., a usage history) may be derived.

[0066] The occupant counting sensor 300 may include a communication circuit 320 configured to send and / or receive digital messages via a communication link using a communication protocol. For example, the communication link may include a wireless communication link, and the communication circuit 320 may include an RF transceiver coupled to an antenna. The communication link may include a wired digital communication link, and the communication circuit 320 may include a wired communication circuit. The communication protocol may include a proprietary protocol, such as the ClearConnect protocol. The control circuit 315 may be configured to send and / or receive digital messages via the communication link during normal operation of the occupant counting sensor 300. For example, the control circuit 315 may be configured to send and / or receive digital messages via the communication link to a system controller (e.g., Figure 1 The control circuit 315 can also receive an indication of an occupant count (or a change thereto) determined for the room by another occupant counting sensor (e.g., an occupant counting sensor installed at a different doorway to the room). In the latter case, the occupant counting sensor 300 can perform some or all of the functions of the system controller, as described herein.

[0067] The occupant counting sensor 300 may include a power supply 322 for generating a DC supply voltage V CC, to power the control circuit 315, the memory 318, the communication circuit 320, and other low voltage circuits of the occupant counting sensor 300. The power supply 322 may include a power supply configured to receive an external supply voltage from an external power source (e.g., an AC mains voltage power supply and / or an external DC power supply). In addition, the power supply 322 may include a battery for powering the circuits of the occupant counting sensor 300.

[0068] Figure 4 4 is a simplified flow chart of an exemplary occupant counting procedure 400. At 410, the occupant counting procedure 400 may be executed (e.g., periodically) by a control circuit of an occupant counting sensor (e.g., the control circuit 315 of the occupant counting sensor 300). At 412, the control circuit may determine, for example, based on a detection signal generated by a detection circuit (e.g., the detection circuit 310), whether motion has been detected at a neighboring occupant counting sensor (e.g., if any of the PIR elements detect a change in IR energy). For example, at 412, the control circuit may compare the amplitude of the detection signal to a motion threshold to determine whether motion has been detected. If motion is detected at 412 (e.g., the amplitude of the detection signal is greater than the motion threshold), then at 414 the control circuit may begin sampling the output of the detection circuit for a period of time and / or until a number of samples (e.g., n samples of the output voltage) have been collected / stored. The duration of the sampling period and / or the number of samples to be collected may be preconfigured and stored in a memory of the occupant counting sensor.

[0069] At 416, the control circuit may determine (e.g., identify) a maximum amplitude (e.g., a peak voltage having a positive polarity) and a minimum amplitude (e.g., a peak voltage having a negative polarity) of the collected samples. At 418, the control circuit may determine whether the collected samples represent a valid signal generated in response to an occupant entering or exiting a space monitored by the occupant counting sensor based on the maximum amplitude and the minimum amplitude of the sample signals. The control circuit may determine whether the collected samples represent a valid signal generated in response to an occupant entering or exiting a space monitored by the occupant counting sensor by checking whether the maximum amplitude and the minimum amplitude of the samples have opposite polarities and / or whether the respective absolute values ​​of the maximum amplitude and the minimum amplitude exceed respective maximum and minimum thresholds (e.g., a preconfigured threshold V TH-MAX and V TH-MIN ,like Figure 3B The threshold V TH-MAX and V TH-MIN The absolute values ​​of may be the same or may be different from one another. A continuous output signal, such as an output signal generated in response to an occupant stopping at a doorway and / or a continuous flow of people through a doorway in which the sensor is installed (e.g., a conga dance), may not exhibit the above-described pattern and, therefore, may not generate a response from the control circuit.

[0070] If the control circuit determines that the collected samples represent a valid signal associated with an occupant entering or exiting the space (e.g., the maximum and minimum amplitudes of the samples have opposite polarities (e.g., bipolar), and the absolute values ​​of the maximum and minimum amplitudes exceed the absolute values ​​of corresponding thresholds), then at 420 the control circuit may also determine whether the pattern reflected in the collected samples corresponds to an occupant entering the space or to an occupant exiting the space. As described herein, the corresponding patterns associated with occupants entering and exiting the space may be determined based on the mounting orientation of the occupant counting sensor, which may be indicated to the control circuit via a switching device (e.g., orientation switch 206). Also as described herein, the patterns associated with occupants entering and exiting the space may include a peak positive voltage followed by a peak negative voltage, a peak negative voltage followed by a peak positive voltage, and / or vice versa.

[0071] If the pattern of collected samples indicates that an occupant has entered the space, the control circuit may increment an occupant count (e.g., a sensor occupant count) at 422. Otherwise, the control circuit may decrement the occupant count at 424. After adjusting the occupant count, the control circuit may wait for a blanking period (e.g., having a configurable duration) at 426, and then check again at 428 whether another motion has been detected adjacent to the occupant counting sensor. The blanking period may prevent the control circuit from responding to any residual peaks in the signal generated by the detection circuit due to an occupant entering or exiting the room. If there is motion at 428, the control circuit may repeat the actions described above. If there is no motion at 428, the control circuit may enter a sleep mode at 430 for a preconfigured period of time, or until the control circuit is notified that motion has been detected in its vicinity. The control circuit may then exit procedure 400 at 432.

[0072] When the control circuit determines at 412 that no motion is detected, the control circuit may also enter a sleep mode at 430 .

[0073] Figure 5 An exemplary occupant counting sensor 500 (eg, Figure 1Occupant counting sensor 190) is configured to detect occupants (e.g., people and / or energy emitters) entering or exiting a space (e.g., a room). Occupant counting sensor 500 can be installed near a doorway 502 of the space and therefore have a field of view of doorway 502. For example, occupant counting sensor 500 can be placed near the upper side of doorway 502 (e.g., the upper center section of the doorway), the upper corner or lower corner of doorway 502, the middle section of doorway 502, the left or right side of doorway 502, and / or the inside or outside of doorway 502. Occupant counting sensor 500 can be mounted to doorframe 504 around doorway 502, to the interior of doorframe 504, and / or otherwise mounted to the structure around doorframe 504 to appropriately detect occupants moving through doorway 502. Additionally, although Figure 5 Only one occupant counting sensor is shown in FIG, but multiple such sensors may be installed at various locations near doorway 502 to improve the accuracy of detecting persons entering or exiting the space.

[0074] The occupant counting sensor 500 may include a detection circuit (not shown) configured to detect one or more occupants (e.g., energy emitters) in a coverage area (e.g., an area near a doorway 502) and generate one or more signals indicating the location of the one or more occupants in the coverage area. The detection circuit may be configured to generate an occupant map, for example, a two-dimensional (2D) map or image indicating the location of the occupants. The occupant map may also include a three-dimensional (3D) map or image. For example, the detection circuit may include a thermopile array, such as an N×N array of thermal response elements. The detection circuit may include an array of microbolometers (e.g., an N×N array of thermal response elements) or another suitable type of thermal camera or detector. The thermal response elements may be sensitive to thermal energy levels at various points in the coverage area 501 and may be operable to convert thermal energy into electrical signals indicating thermal energy levels in the coverage area. Thus, the output of the thermopile array may represent an occupant map (e.g., a 2D thermal image or thermal map) of the coverage area 501, wherein each thermal response element of the thermopile array corresponds to a pixel in the thermal map. As a heat generating object (e.g., a person or occupant) moves in and out of the coverage area 501 and / or moves through the coverage area 501, the output of the thermopile array (e.g., a 2D thermal image) can indicate changes (or lack of changes) in the thermal energy level at various points of the coverage area. Thus, the output can be used to determine the location of the heat generating object in the coverage area 501. The detection circuitry can also include radar sensing circuitry, visible light sensing circuitry (e.g., a camera), and / or time of flight sensing circuitry (e.g., as described in more detail below).

[0075] The occupant counting sensor 500 may also include a control circuit (not shown) coupled to the detection circuit (e.g., a thermopile array) and configured to receive an output signal of the detection circuit (e.g., an occupant map). The control circuit may include, for example, a microprocessor, a programmable logic device (PLD), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or any suitable processing device. The control circuit may be configured to process the output signal of the detection circuit (e.g., an occupant map) and determine the location and / or movement of a person in the coverage area 501 based on the processed output signal. For example, the occupant map may be used to monitor the coverage area 501 near a doorway 502. The coverage area 501 may include multiple zones. A first zone (e.g., Figure 5 Zone A 508 shown in FIG. 504 may correspond to an area outside of doorway 502 (eg, outside of a space or room), a second zone (eg, Figure 5 Zone B 510 shown in FIG. 5 ) may correspond to all or a portion of doorway 502, and a third zone (e.g., Figure 5 Zone C 512 shown in the figure may correspond to an area on the inside of the doorway 502 (e.g., the interior of a space or room). The control circuit may detect the position and / or movement of a person relative to the multiple zones 508-512 in response to receiving an output signal from the detection circuit (e.g., an occupant map), and determine whether the person has entered or exited the space based on the detected position and / or movement of the person. For example, if the control circuit determines that a person has moved through multiple zones in a first order (e.g., from zone A 508 through zone B 510 to zone C 512) based on the output signal of the detection circuit (e.g., an occupant map), the control circuit may also determine that the person has entered the space. Similarly, if the control circuit determines that a person has moved through multiple zones in a second order (e.g., from zone C 512 through zone B 510 to zone A 508) based on the output signal of the detection circuit (e.g., an occupant map), the control circuit may also determine that the person has left the space.

[0076] The control circuitry may determine an occupant count of the space in response to determining that a person has entered or exited the space. For example, the control circuitry may increase the occupant count of the space based on a determination that a person has entered the space, and may decrease the occupant count based on a determination that a person has left the space.

[0077] The occupant counting sensor 500 may be configured to send one or more digital messages to a system controller (e.g., system controller 110) via an RF signal (e.g., using a proprietary protocol described herein) in response to determining an occupant count of a space. The digital message may indicate an occupant count or a change therein. For example, the occupant counting sensor 500 may be a one-way transmitter (e.g., may not be configured to receive digital messages) and may be configured to periodically send a sensor occupant count indicating a change in the number of occupants since the last transmission from the occupant counting sensor 500. The occupant counting sensor 500 may be configured to reset the occupant count stored in a memory at the occupant counting sensor after the occupant counting sensor sends a change in the occupant count. For example, the sensor occupant count may be positive or negative based on how many occupants have entered or exited the space since the last reset of the occupant count. The system controller may be configured to maintain a central occupant count of the space. For example, the system controller may add a sensor occupant count (e.g., indicating a change in the occupant count of the space) to the central occupant count in response to receiving a sensor occupant count from the occupant counting sensor 500.

[0078] The occupant counting sensor 500 may include a switch (not shown) that may be manipulated to inform the occupant counting sensor 500 of the orientation and / or location of the installation (e.g., whether the occupant counting sensor is installed to the center of the doorway 502, on the left or right side of the doorway 502, and / or on the inside or outside of the doorway 502). Based on the orientation, the occupant counting sensor 500 may know which particular output signal corresponds to which direction of movement. For example, when the occupant counting sensor 500 is installed in a first orientation, the sensor may associate a first output signal pattern with a person entering through the doorway 502. When the occupant counting sensor 500 is installed in a second orientation, the sensor may associate a second output signal pattern with a person leaving through the doorway 502.

[0079] Figure 6 is an exemplary occupant counting sensor 600 (e.g., Figure 5 6 is an exemplary block diagram of an occupant counting sensor 500). The occupant counting sensor 600 may include a detection circuit 610 and a control circuit 615. The detection circuit 610 may be configured to generate an occupant map, for example, a two-dimensional (2D) map or image indicating the locations of occupants. The occupant map may also include a three-dimensional (3D) map or image. For example, the detection circuit 610 may include a thermopile array 612 (e.g., N×N thermally responsive elements, where N may equal 8). The thermally responsive elements may be capable of detecting occupants from a coverage area (e.g., Figure 5501) and generates one or more signals representing an occupant map (e.g., a 2D thermal image or a thermal map) of the area. Each thermal response element can correspond to a pixel in the occupant map (e.g., a 2D thermal image), and the signal generated by the thermal response element can represent the thermal energy level at the corresponding point of the coverage area. Therefore, the output of the detection circuit 610 can be used to determine the location of the occupant (e.g., energy emitter) in the coverage area (e.g., because the thermal energy level at the location of the energy emitter may be different from the thermal energy level at other locations of the coverage area).

[0080] The control circuit 615 may be configured to receive the signals generated by the detection circuit 610 and determine the XY coordinates of an occupant map (e.g., a 2D thermal image) or an occupant (e.g., an energy emitter) in the area covered by the detection circuit 610. The control circuit 615 may include an occupant map processing unit 630 (e.g., a software module for processing an occupant map), an occupant tracking filter 632 (e.g., a software module implementing a Kalman tracking filter), and / or a control unit 634 (e.g., a control software module). The control circuit 615 may include a microprocessor, a programmable logic device (PLD), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or any suitable processing device that may be configured to perform the functions of the occupant map processing unit 630, the occupant tracking filter 632, and / or the control unit 634. Although shown as including all three of the occupant map processing unit 630, the occupant tracking filter 632, and / or the control unit 634, the control circuit may also include a subset of these components.

[0081] The occupant map processing unit 630 may be configured to receive input from the detection circuit 610 and output an occupant map or preliminary coordinates of an occupant in the area covered by the occupant counting sensor 600. The input received from the detection circuit 610 may represent, for example, a plurality of pixels of an occupant map of the covered area (e.g., a 2D thermal image), and the occupant map processing unit 630 may identify which one or more pixels of the occupant map represent (e.g., are covered by) an occupant (e.g., an energy emitter). For example, the identification may be performed by comparing the thermal energy level at each pixel of the 2D thermal image generated by the detection circuit 610 with a predetermined threshold, and determining that the pixel is covered by an energy emitter if the thermal energy level at the pixel exceeds the predetermined threshold.

[0082] Upon identifying one or more pixels of the occupant map representing an occupant, the occupant map processing unit 630 may also determine the XY coordinates of the occupant. For example, if the occupant occupies only one of the pixels of the occupant map, the occupant map processing unit 630 may determine the XY coordinates of the occupant based on the position of the pixel in the occupant map. If the energy emitter occupies multiple pixels of the occupant map, the occupant map processing unit 630 may determine the XY coordinates of the occupant based on the centroid of the multiple pixels (e.g., based on the center pixel of the multiple pixels).

[0083] The XY coordinates determined by the occupant map processing unit 630 may deviate from the actual coordinates of an occupant in the occupant map or coverage area covered by the detection circuit 610 (e.g., due to errors introduced when measuring thermal energy levels). Such deviations may be reduced or eliminated by further processing the XY coordinates determined by the occupant map processing unit 630 using a filter (e.g., occupant tracking filter 632) and obtaining improved XY coordinates of the occupant at the output of the filter.

[0084] The XY coordinates of the occupant (e.g., improved XY coordinates) can be provided to the control unit 634 and used to determine the movement of the occupant in the area covered by the detection circuit 610. As described herein, the coverage area of ​​the detection circuit 610 can include multiple zones (e.g., Figure 5 508-512 shown in FIG. 5 ). These zones may correspond to, for example, areas near an entrance or exit of a space. Thus, by tracking the movement of occupants in these zones, the control unit 634 may determine whether an occupant has entered or exited the space. For example, the control unit 634 may use a state machine to track occupants moving through zones of the coverage area. The control unit 634 may be configured to track multiple occupants within the coverage area. For example, the control unit 634 may use a separate state machine for each of the multiple occupants in the coverage area.

[0085] When tracking an occupant entering a space, the control unit 634 may initially determine, based on the occupant's XY coordinates, that the occupant has entered a first zone (e.g., Figure 5 In response to detecting an occupant in the zone, the control unit 634 may assign an identifier (e.g., a tracking number) to the occupant. Subsequently, the control unit 634 may determine that the occupant has moved from the first zone through the second zone (e.g., Figure 5 510) into a third zone (eg, Figure 5In response to detecting that an occupant enters a first zone, moves through the zones, and exits a last zone, the control unit 634 may determine that the occupant has entered the space.

[0086] Similarly, after initially detecting the occupant, the control unit 634 may later determine, based on the occupant's XY coordinates and the identifier assigned to the occupant, that the occupant has moved from the third zone through the second zone into the first zone. In this case, the control unit 634 may determine that the occupant has left the space and may disassociate the occupant from the identifier assigned to the occupant.

[0087] In some cases, the control unit 634 may lose track of the occupant or determine that the tracked occupant has shown a lack of movement (e.g., no movement for a preconfigured duration). In response, the control unit 634 may mark the occupant as a stalled occupant (e.g., in a stalled state) and may disassociate the occupant from the identifier previously assigned to the occupant. Subsequently, if the control unit 634 detects the occupant again (e.g., when the occupant enters zone A, zone B, or zone C), or if the control unit 634 determines that the occupant has resumed movement, the control unit 634 may assign a new identifier to the occupant and begin tracking the occupant again.

[0088] The occupant counting sensor 600 can more accurately detect when an occupant enters or leaves a space by tracking the occupant's movement through multiple zones of a two-dimensional area and determining whether the occupant has entered or exited the space based on the tracked movement. Using these techniques, the occupant counting sensor 600 can avoid erroneously determining the entry or exit status of an occupant relative to a particular space. For example, if an occupant lingers at a doorway of the space (e.g., if an occupant enters Figure 5 B zone shown in FIG but not leaving), the control unit 634 may not make a determination regarding the occupant's entry or exit status until further movement of the occupant is detected (e.g., until the occupant moves into Figure 5 A zone or C zone shown in ).

[0089] The control unit 634 may maintain an occupant count for the space that the control unit is configured to monitor. If the control unit 634 determines that an occupant has entered the space, the control circuit 634 may increase the occupant count accordingly. If the control unit 634 determines that an occupant has left the space, the control circuit 634 may decrease the occupant count accordingly. If the occupant count is greater than zero, the control unit 634 may additionally infer that the space is occupied. When the occupant count drops to zero, the control unit 634 may infer that the space has become unoccupied.

[0090] The occupant counting sensor 600 may include an orientation switch 616. The orientation switch 616 may be manipulated to inform the occupant counting sensor 600 about the orientation of the installation (e.g., whether the occupant counting sensor is installed to the center of the doorway 502, on the left or right side of the doorway 502, and / or inside or outside the doorway 502). Based on the orientation, the occupant counting sensor 600 may know how to interpret the signals (e.g., 2D thermal images) received from the detection circuit 610 in order to determine the location (e.g., XY coordinates) and / or movement of the occupant.

[0091] The occupant counting sensor 600 may include a memory 618 configured to store XY coordinates of an occupant provided by the occupant map processing unit 630 and / or the occupant tracking filter 632. As described herein, the memory 618 may also be configured to store information about one or more zones of the coverage area (e.g., boundary information). The memory 618 may also be configured to store an identifier of the occupant (e.g., a tracking number) and a state of the state machine (e.g., which zone(s) of the coverage area the occupant is in) and / or an XY coordinate associated with the tracking number. As described herein, the control unit 634 may use the stored information to track the movement of the occupant and / or determine the entry / exit state of the occupant. When the occupant exits the coverage area, the tracking number and the associated state machine state (e.g., XY coordinates) may be deleted from the memory 618. The memory 618 may also be configured to store occupant counts and / or occupancy states of the space. For example, the control unit 634 may be configured to save different occupant counts associated with different time periods in the memory 618 so that a historical view of the occupancy status of the space (e.g., a usage history) may be derived. Additionally, operating parameters of the occupant counting sensor 600 may also be stored in the memory 618. For example, the control unit 634 may be configured to store thresholds for determining whether a pixel in the occupant map corresponds to an occupant in the memory 618. The memory 618 may be implemented as an external integrated circuit (IC) coupled to the control circuit 615 or as an internal circuit of the control circuit 615.

[0092] The occupant counting sensor 600 may include a communication circuit 620 configured to send and / or receive digital messages via a communication link using a communication protocol. For example, the communication link may include a wireless communication link, and the communication circuit 620 may include an RF transceiver coupled to an antenna. The communication link may include a wired digital communication link, and the communication circuit 620 may include a wired communication circuit. The communication protocol may include a proprietary protocol, such as the ClearConnect protocol. The control circuit 615 may be configured to send and / or receive digital messages via the communication link during normal operation of the occupant counting sensor 600. For example, the control circuit 615 may be configured to use the communication circuit 620 to send and / or receive digital messages to a system controller (e.g., Figure 1 The control circuit 615 can also receive an indication of an occupant count (or a change thereto) for the space as determined by another occupant counting sensor (e.g., an occupant counting sensor installed at a different doorway to the space). In the latter case, the occupant counting sensor 600 can perform some or all of the functions of the system controller, as described herein.

[0093] The occupant counting sensor 600 may include a power supply 622 for generating a DC supply voltage V CC , to power the detection circuit 610, the control circuit 615, the memory 618, the communication circuit 620, and other low voltage circuits of the occupant counting sensor 600. The power supply 622 may include a power supply configured to receive an external supply voltage from an external power source (e.g., an AC mains voltage power supply and / or an external DC power supply). In addition, the power supply 622 may include a battery for powering the circuits of the occupant counting sensor 600.

[0094] The detection circuit 610 may also include a radar sensing circuit, a visible light sensing circuit, and / or a time of flight sensing circuit. For example, when the detection circuit 610 includes a radar sensing circuit, the occupant map processing unit 630 of the control circuit 615 may include a radar detection software module. The radar sensing circuit may include: a transmitting antenna array (e.g., a phased array) coupled to the control circuit 615 (e.g., a radar detection software module) via a radar transmitter circuit; and / or a receiving antenna array (e.g., a phased array) coupled to the control circuit 615 (e.g., a radar detection software module) via a radar receiver circuit. In addition, when the detection circuit 610 includes a visible light sensing circuit, the occupant map processing unit 620 of the control circuit 615 may include an image processing software module. The visible light sensing circuit may include a camera configured to record an image of a space, and the image of the space may be received by the image processing software module of the control circuit 615.

[0095] Fig. 7A is an occupant counting sensor (e.g., Figure 5 Occupant counting sensor 500 and / or Figure 6 An exemplary state diagram of an occupant counting sensor 600 of the present invention may be used to determine the movement of an occupant (e.g., an energy emitter). The occupant counting sensor may use a separate state machine to track each occupant in the coverage area. The occupant counting sensor may be in an idle state before detecting an occupant that may enter the space (e.g., when there are no occupants in the coverage area). An occupant may enter a first zone (e.g., zone A) of an area monitored by the occupant counting sensor. Such entry may be detected by an occupant counting sensor (e.g., as described herein), and the occupant counting sensor may assign an identifier (e.g., a tracking number) to the detected occupant. The occupant counting sensor may save the identifier, the state of the state machine (e.g., the zone of the coverage area in which the occupant is located), and / or the location (e.g., XY coordinates) of the occupant in a memory (e.g., memory 618) of the occupant counting sensor. When the occupant moves from the first zone to the second zone (e.g., zone B), the occupant counting sensor may track (e.g., record) the movement (e.g., using an occupant tracking filter 632), for example, based on updated coordinates of the occupant and / or the identifier assigned to the occupant. The occupant counting sensor may similarly track the movement of the occupant as the occupant moves from the second zone to the third zone (e.g., zone C). When the occupant exits the third zone, the occupant detection sensor may no longer detect the occupant of the coverage area. In response to detecting the movement of the occupant through the first zone, the second zone, and the third zone (e.g., in the particular order) and then exiting the third zone, the occupant counting sensor may determine that the occupant has entered the space. Therefore, the occupant counting sensor may increase the occupant count of the space to reflect that the occupant has entered the space. The occupant counting sensor may then disassociate the occupant from the identifier previously assigned to the occupant (e.g., the occupant counting sensor may destroy the identifier assigned to the occupant) and eliminate the instance of the state machine. The occupant counting sensor may then re-enter the idle state.

[0096] While in any of the first, second, or third zones, the occupant may become stationary (e.g., exhibiting a lack of movement and / or lingering in a doorway) or undetectable (e.g., the occupant has exited a coverage area monitored by the occupant counting sensor). In those situations, the occupant counting sensor may deem the occupant to have entered a quiescent state or a stationary state, and thus, the occupant counting sensor may disassociate the occupant from an identifier previously assigned to the occupant (e.g., the occupant counting sensor may destroy the identifier assigned to the occupant) and eliminate the instance of the state machine. Additionally, the occupant counting sensor may determine that the occupant has moved backwards, e.g., from the third zone to the second zone, or from the second zone to the first zone.

[0097] Figure 7B is an occupant counting sensor (e.g., Figure 5 Occupant counting sensor 500 and / or Figure 6 An exemplary state diagram of an occupant counting sensor 600 of the present invention can be used to determine the movement of an occupant. The occupant counting sensor can use a separate state machine to track each occupant in the coverage area. As described above, the occupant counting sensor can be in an idle state before detecting an occupant that may enter the space. The occupant can be detected by the occupant counting sensor in the third zone (e.g., zone C). In response to the detection, the occupant counting sensor can assign an identifier to the occupant. The occupant counting sensor can save the identifier, the state of the state machine (e.g., the zone of the coverage area), and / or the location of the occupant in a memory (e.g., memory 618) of the occupant counting sensor (e.g., XY coordinates). When the occupant moves from the third zone to the second zone (e.g., zone B), the occupant counting sensor can track (e.g., record) the movement (e.g., using occupant tracking filter 632), for example, based on the occupant's updated coordinates and / or the identifier assigned to the occupant. When the occupant moves from the second zone to the first zone (e.g., zone A), the occupant counting sensor can similarly track the movement of the occupant. When the occupant exits the first zone, the occupant detection sensor may no longer detect the occupant in the coverage area. In response to detecting the movement of the occupant through the third zone, the second zone, and the first zone (e.g., in the particular order) and then exiting the first zone, the occupant counting sensor can determine that the occupant has left the space. Therefore, the occupant counting sensor can reduce the occupant count maintained for the space. The occupant counting sensor can then disassociate the occupant from the identifier previously assigned to the occupant (e.g., the occupant counting sensor can destroy the identifier assigned to the occupant) and eliminate the instance of the state machine. The occupant counting sensor can then re-enter the idle state.

[0098] While in any of the first, second, or third zones, the occupant may become stationary (e.g., exhibiting a lack of movement and / or lingering in a doorway) or undetectable (e.g., the occupant has exited the coverage area monitored by the occupant counting sensor). In that case, the occupant counting sensor may deem the occupant to have entered a quiescent state or a stationary state, and thus, the occupant counting sensor may destroy the identifier assigned to the occupant and eliminate the instance of the state machine. Additionally, the occupant counting sensor may determine that the occupant has moved backwards, e.g., from the first zone to the second zone, or from the second zone to the third zone.

[0099] Although described herein as including a thermopile array, an occupant counting sensor (e.g., occupant counting sensor 500 or occupant counting sensor 600) may alternatively or additionally include a radar sensing circuit. Such radar sensing circuitry may in turn include: a radar detection processor; a transmit antenna array (e.g., a phased array) coupled to the radar detection processor (e.g., via a radar transmitter circuit); and / or a receive antenna array (e.g., a phased array) coupled to the radar detection processor (e.g., via a radar receiver circuit). The radar sensing circuitry may be implemented using modulated continuous wave radar technology or other types of radar technology, such as pulse radar, continuous wave radar, side aperture radar, phased array radar, monostatic radar, multistatic radar, etc. The radar detection processor may be configured to transmit a radar signal (e.g., a chirp) via a transmit antenna array and receive reflected signals via a receive antenna array. The radar signal may be a frequency modulated continuous waveform (FMCW) that increases in frequency over a period of time. The radar sensing circuitry may be configured to process the reflected signal (eg, compared to the transmitted radar signal) to determine a Doppler shift of the reflected signal and data about an occupant of the space, such as a distance to the occupant, a direction of movement of the occupant, and / or an acceleration of the occupant.

[0100] The radar detection processor can be configured to use a transmitting antenna array and a receiving antenna array to measure the angle at which a moving object (e.g., an occupant) can be detected. The radar detection processor can be configured to measure various detection angles and determine data about the moving object at each detection angle. The radar detection processor can send a radar signal at each detection angle and receive a reflected signal for processing. The radar detection processor can be configured to construct a map (e.g., a two-dimensional or three-dimensional map) of the moving objects in the area monitored by the radar sensing circuit based on the data about the moving object determined at each detection angle. The map can be constructed in a manner similar to the thermal map or 2D thermal image described in conjunction with the thermopile array, at least in terms of how the map can be used to determine the position (e.g., XY coordinates) of the moving object in the map or the area covered by the map. Such a map can be used to determine the entry / exit status of the moving object and / or the number of occupants in the monitored area. Therefore, the above-described technology for tracking a moving object through multiple zones to determine the entry, exit, or standstill status of the moving object (e.g., as Fig. 7A and Figure 7B ) may be equally applicable to an occupant counting sensor including a radar sensing circuit. For example, when the occupant counting sensor includes a radar sensing circuit, the occupant tracking filter may be implemented as an extended Kalman tracking filter.

[0101] The occupant counting sensors described herein (e.g., occupant counting sensor 500 or occupant counting sensor 600) may include a visible light sensing device that utilizes a camera pointed at an area of ​​interest in a space to record images of the area. These images may contain information about one or more characteristics of the area (such as the movement of objects in the area). The images may be processed (e.g., a thermal map similar to the 2D thermal images described above) to determine occupancy status and / or occupant counts of the area. Thus, the techniques described above regarding tracking a moving object through multiple zones to determine entry, exit, or stasis states of the moving object (e.g., as Fig. 7A and Figure 7B ) may be equally applicable to occupant counting sensors including visible light sensing devices. Examples of visible light sensing devices are described in more detail in commonly assigned U.S. Patent Application Publication No. 2017 / 0171941, published on June 15, 2017, and U.S. Patent Application Publication No. 2018 / 0168019, published on June 14, 2018 (both entitled “LOAD CONTROL SYSTEM HAVING A VISIBLE LIGHT SENSOR”), the entire disclosures of which are incorporated herein by reference.

[0102] Additionally, the occupant counting sensors described herein (e.g., occupant counting sensor 500 or occupant counting sensor 600) may include time-of-flight sensing circuitry. In addition to providing XY coordinates, the time-of-flight sensing circuitry may also provide a Z coordinate of an occupant in the coverage area (e.g., the Z coordinate may indicate a distance from the occupant counting sensor to the occupant). The XYZ coordinates of the occupant may indicate the location of the occupant in the coverage area, and thus may be used to track the movement of the occupant in a manner similar to that described herein. Thus, the techniques described above regarding tracking a moving object through multiple zones in order to determine an entry, exit, or standstill state of the moving object (e.g., as described herein) may be used to track the movement of the occupant in the coverage area. Fig. 7A and Figure 7B ) may be equally applicable to an occupant counting sensor including a time-of-flight sensing circuit.

[0103] The accuracy of the occupant counting sensors described herein may be affected by many factors. For example, multiple people walking side by side through a doorway, walking through a doorway right behind each other, or standing in a doorway may confuse the occupant counting sensor. The occupant counting sensor may also suffer from false tripping interference caused by one or more components of the occupant counting sensor. To prevent and / or reduce the effects of these factors over time, for example, to prevent any false counts from persisting or propagating to different time periods, the occupant counting sensor can be configured to periodically reset its occupant counter.

[0104] In an example, an occupant counting sensor may be configured to reset an occupant count maintained by the sensor (e.g., a sensor occupant count) when sending the count to another device (e.g., to a system controller), when persisting the count to a memory, etc. For example, the system controller may maintain a room occupant count in response to receiving a sensor occupant count from an occupant counting sensor.

[0105] Resetting the occupant count can allow the occupant counting sensor to effectively only report changes in the number of occupants in the space. To illustrate, an occupant counting sensor may falsely count five people entering a room when in fact only four people entered that room. By being able to reset the occupant count to zero and effectively only determine / report changes in the number of occupants in the room, the occupant counting sensor can still correctly determine / report the number of people leaving the room after one or more factors that caused the false count are removed or corrected.

[0106] As described herein, an occupant counting sensor (e.g., occupant counting sensor 190, occupant counting sensor 200, occupant counting sensor 300, occupant counting sensor 500, and / or occupant counting sensor 600) may report occupant counts or changes thereto to another device. Such other device may be a system controller (e.g., system controller 110), another occupant counting sensor (e.g., that performs some or all of the functions of the system controller), etc. The receiving device may be configured to maintain occupant counts (e.g., room occupant counts) for one or more user spaces and adjust these counts based on information received from the sending sensors.

[0107] Figure 8 8 is a communication sequence diagram depicting an exemplary message flow (e.g., a digital message flow) in a system 800, the system 800 including two occupant counting sensors 810, 812 (e.g., occupant counting sensors 190, 300, 500, 600) and a system controller (e.g., system controller 110). For example, the occupant counting sensors 810, 812 can be installed at different doorways and / or entrances to a room to detect occupants entering and / or exiting the room. The system controller 814 can maintain a room occupant count in response to the two occupant counting sensors 810, 812. The occupant counting sensors 810, 812 can each send (e.g., periodically send) a corresponding sensor occupant count to the system controller 814, wherein the corresponding sensor occupant count can indicate a change in the room occupant count since the last time the sensor occupant count was sent.

[0108] For example, at 820, the first occupant count sensor 810 may detect an occupant entering the room and may send a sensor occupant count of positive 1 to the system controller 814 at 822. At 824, the first occupant count sensor 810 may reset its sensor occupant count to zero (e.g., after sending the sensor occupant count at 822). After receiving the sensor occupant count sent at 822, the system controller 814 may increment the room occupant count by 1 at 826. At 828 and at 830, the second occupant count sensor 812 may detect an occupant entering the room. At 832, the second occupant count sensor 812 may send a sensor occupant count of positive 2 to the system controller 814 and reset its sensor occupant count to zero at 834. After receiving the sensor occupant count sent at 832, the system controller 814 may increment the room occupant count by 2 at 836.

[0109] At 838, the first occupant counting sensor 810 may detect an occupant exiting the room, at 840, an occupant entering the room, and at 842, an occupant exiting the room. At 844, the first occupant counting sensor 810 may transmit a sensor occupant count of negative 1, and reset its occupant count to zero at 846. After receiving the sensor occupant count transmitted at 844, the system controller 814 may subtract 1 from the room occupant count at 848. At 850 and 852, the second occupant counting sensor 812 may detect an occupant entering the room, and at 854, an occupant exiting the room. At 856, the second occupant counting sensor 812 may transmit a sensor occupant count of positive 1, and reset its occupant count to zero at 858. After receiving the sensor occupant count transmitted at 856, the system controller 814 may increment the room occupant count by 1 at 860.

[0110] Fig. 9 A flow chart of an example procedure 900 for sending and resetting a sensor occupant count at an occupant counting sensor is shown. At 910, the procedure 900 may be performed (e.g., periodically) by a control circuit of an occupant counting sensor (e.g., the control circuit 315 of the occupant counting sensor 300 and / or the control circuit 615 of the occupant counting sensor 600). At 912, before the procedure 900 exits, the control circuit may send the occupant count maintained by the occupant counting sensor to another device (e.g., a system controller, another occupant counting sensor, another device of a load control system to which the sensor belongs, etc.). After sending, at 914 the control circuit may reset the occupant count to zero so that the occupant count may be restarted.

[0111] Fig.10 A flow chart of an exemplary occupant counting receiving procedure 1000 is shown. At 1010, the exemplary receiving procedure 1000 may be performed by a receiving device, such as a system controller (e.g., system controller 110), a control circuit of another occupant counting sensor (e.g., control circuit 315 of occupant counting sensor 300 and / or control circuit 615 of occupant counting sensor 600), etc. At 1012, the receiving device may receive occupant counting information (e.g., sensor occupant count) related to the number of people occupying a particular user space, or changes thereto, from an occupant counting sensor (e.g., occupant counting sensor 200 or occupant counting sensor 600). The occupant counting information may be included in one or more digital messages and sent to the receiving device via a wired or wireless communication link, for example, as described herein.

[0112] The receiving device may maintain an overall occupant count (e.g., a room occupant count) for the user space, and may additionally maintain historical room occupant data for the user space. The historical room occupant data may, for example, include respective room occupant counts associated with various points in time (e.g., various time periods). In response to receiving occupant count information from an occupant counting sensor, at 1014, the receiving device may adjust a total occupant counter for the user space based on the received information. For example, when a positive occupant count is received from the occupant counting sensor, the receiving device may increase the total occupant count, and when a negative occupant count is received from the occupant counting sensor, the receiving device may decrease the total occupant count. The receiving device may also maintain a total occupant counter when the occupant count from the occupant counting sensor is zero.

[0113] The receiving device may be able to correct any erroneous counts of occupants based on other information obtained by the receiving device. For example, at 1015, the receiving device may determine whether the room occupant count is less than zero. If the determination at 1015 is that the room occupant count is less than zero, the receiving device may determine that there is an error in the count and may correct the error. For example, at 1020, the receiving device may update the historical room occupant count data for the user space by adding the value of the erroneous count to each relevant data point (e.g., each occupant count associated with the corresponding time period). Additionally, at 1022, the receiving device may zero the total occupant counter by resetting the total occupant counter to zero. The receiving device may then exit procedure 1000 at 1024.

[0114] At 1016, the receiving device may determine whether the user space is occupied based on information received from an occupancy sensor (e.g., occupancy sensor 180) installed in the user space. If it is determined at 1016 that the user space is not occupied, but it is determined at 1018 that the total occupant counter of the user space is greater than zero, the receiving device may determine that there is an error in the count and may correct the error. For example, at 1020, the receiving device may update the historical room occupant count data for the user space by subtracting the value of the erroneous count from each relevant data point (e.g., each occupant count associated with the corresponding time period). In addition, at 1022, the receiving device may zero the total occupant counter by resetting the total occupant counter to zero. The receiving device may then exit procedure 1000 at 1024.

[0115] If it is determined at 1016 that the user space is occupied, and it is determined at 1018 that the total occupant counter of the user space is greater than zero, the receiving device can determine that the count is not erroneous, and can exit the procedure 1000 at 1024. And once it is determined at 1012 that no occupant count is received, the receiving device can also exit the procedure 1000.

[0116] As described herein, a receiving device may be configured to receive occupant counting information from more than one occupant counting sensor (e.g., when a user space has multiple doorways, each of which is monitored by a sensor). In those cases, the receiving device may be able to integrate the occupant counting information received from the multiple sensors and adjust the total occupant counter of the user space accordingly.

[0117] Fig.11 1 is a block diagram illustrating an example system controller 1100 (such as the system controller 111 described herein) that may be configured to execute the program 1000. The system controller 1100 may include a control circuit 1102 for controlling the functions of the system controller 1100, including executing the program 1000. The control circuit 1102 may include one or more general purpose processors, special purpose processors, conventional processors, digital signal processors (DSPs), microprocessors, integrated circuits, programmable logic devices (PLDs), application specific integrated circuits (ASICs), etc. The control circuit 1102 may perform signal encoding, data processing, image processing, power control, input / output processing, or any other function that enables the system controller 1100 to perform the functions described herein. The control circuit 1102 may store information in and / or retrieve information from a memory 1104. The memory 1104 may include non-removable memory and / or removable memory. The non-removable memory may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of non-removable memory. The removable memory may include a Subscriber Identity Module (SIM) card, a memory stick, a memory card, or any other type of removable memory.

[0118] The system controller 1100 may include a communication circuit 1106 for sending and / or receiving information. The communication circuit 1106 may perform wireless and / or wired communications. The system controller 1100 may also or alternatively include a communication circuit 1108 for sending and / or receiving information. The communication circuit 1108 may perform wireless and / or wired communications. The communication circuits 1106 and 1108 may communicate with the control circuit 1102. The communication circuits 1106 and 1108 may include an RF transceiver or other communication module capable of performing wireless communications via an antenna. The communication circuit 1106 and the communication circuit 1108 may be capable of performing communications via the same communication channel or different communication channels. For example, the communication circuit 1106 may be capable of communicating via a wireless communication channel (e.g., Near Field Communication (NFC), Threads, cellular, etc.) (e.g., with a network device, through a network, etc.), and the communication circuit 1108 may be able to communicate via another wireless communication channel (e.g., or proprietary communication channels such as CLEAR CONNECT TM ) (e.g., communicating with control devices and / or other devices in a load control system).

[0119] The control circuit 1102 may communicate with an LED indicator 1112 for providing an indication to the user. The control circuit 1102 may communicate with an actuator 1114 (e.g., one or more buttons) that may be actuated by the user to communicate the user selection to the control circuit 1102. For example, the actuator 1114 may be actuated to place the control circuit 1102 in an association mode and / or to communicate an association message from the system controller 1100.

[0120] Each of the modules within the system controller 1100 may be powered by a power supply 1116. For example, the power supply 1116 may include an AC power supply or a DC power supply. The power supply 1116 may generate a supply voltage V CC , used to power the modules within the system controller 1100.

[0121] Although features and elements are described herein in specific combinations, each feature or element may be used alone or in any combination with other features and elements. For example, the functions described herein may be described as being performed by a control device such as a remote control device or a lighting device, but may also be similarly performed by a hub device or a network device. The methods described herein may be implemented in a computer program, software, or firmware contained in a computer-readable medium executed by a computer or processor. Examples of computer-readable media include electronic signals (sent via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), removable disks, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)).

Claims

1. A device configured to detect an occupant entering or exiting a space, the device comprising: A detection circuit is configured as follows: detecting the occupant in a coverage area of ​​the space and generating one or more signals indicative of the occupant's location in the coverage area; as well as generating an occupant map indicating the locations of the occupants; as well as A control circuit configured to: receiving the one or more signals from the detection circuit; determining the location of the occupant based on coordinates of the occupant in the occupant map; determining movement of the occupant through a plurality of zones of the coverage area based on the determined location of the occupant, wherein the plurality of zones include a first zone, a second zone, and a third zone, the first zone including an area outside the space and adjacent to an entry location of the space, the second zone including an area at the entry location, and the third zone including an area inside the space and adjacent to the entry location; determining that the occupant has entered the space in response to determining that the occupant has moved from the first zone through the second zone to the third zone; as well as The occupant is determined to have exited the space in response to determining that the occupant has moved from the third zone through the second zone to the first zone.

2. The apparatus of claim 1, wherein the control circuit comprises a Kalman tracking filter, the control circuit being configured to determine the coordinates of the occupant using the Kalman tracking filter.

3. The apparatus of claim 2, wherein the control circuit is configured to determine preliminary coordinates of the occupant in the occupant map based on the one or more signals received from the detection circuit, and to adjust the preliminary coordinates using the Kalman tracking filter.

4. The apparatus of claim 1, wherein the detection circuit comprises a thermopile array having a plurality of thermal sensing elements.

5. The apparatus of claim 4, wherein the occupant map comprises a two-dimensional (2D) thermal image of the coverage area, and wherein the location of the occupant in the coverage area is indicated in the thermal image.

6. The apparatus of claim 1, wherein the detection circuit comprises a visible light sensing circuit having a camera.

7. The apparatus of claim 6, wherein the occupant map comprises a two-dimensional (2D) image of the coverage area, and wherein the locations of the occupants in the coverage area are indicated in the image.

8. The apparatus of claim 1, wherein the detection circuit comprises radar sensing circuitry.

9. The apparatus of claim 8, wherein the occupant map comprises a two-dimensional (2D) occupant map of the coverage area, and wherein the locations of the occupants in the coverage area relative to the plurality of zones are indicated in the occupant map.

10. The apparatus of claim 1, wherein the control circuit is further configured to determine that the occupant has entered a quiescent state based on a lack of movement of the occupant or in response to a loss of detection of the occupant.

11. The apparatus of claim 10, wherein the control circuit is configured to determine that the occupant has entered the quiescent state based on a lack of movement of the occupant during a preconfigured time period.

12. The apparatus of claim 11, wherein the control circuit is configured to assign an identifier to the occupant in response to detecting that the occupant has entered one of the plurality of zones from the standstill state, and the control circuit is further configured to use the identifier to track the movement of the occupant through the plurality of zones.

13. The apparatus of claim 12, wherein the control circuit is configured to disassociate the occupant from the identifier in response to detecting that the occupant has moved from one of the plurality of zones to the standstill state.

14. The apparatus of claim 1, wherein the control circuit is further configured to maintain an occupant count for the space, the control circuit being configured to increase the occupant count in response to determining that the occupant has entered the space and to decrease the occupant count in response to determining that the occupant has exited the space.

15. The apparatus of claim 14, further comprising a communication circuit, wherein the control circuit is configured to send a message indicative of the occupant count via the communication circuit.

16. The apparatus of claim 15, wherein the control circuit is further configured to reset the occupant count to zero after the message is sent.

17. The apparatus of claim 15, wherein the message is sent to a controller external to the apparatus.

18. The apparatus of claim 14, further comprising a communication circuit configured to receive a signal from an occupancy sensor indicating an occupancy condition of the space.

19. The apparatus of claim 18, wherein the control circuit is further configured to set the occupant count to zero when the signal received from the occupancy sensor indicates that the space is unoccupied.

20. The apparatus of claim 14, wherein the control circuit is further configured to maintain historical data indicative of respective occupant counts of the space during various time periods.

21. An occupant detection device, comprising: detection circuitry configured to detect occupants in a coverage area of ​​a space and generate an occupant map indicating locations of the occupants in the coverage area; as well as A control circuit configured to: determining the location of the occupant based on coordinates of the occupant in the occupant map; determining movement of the occupant through a plurality of zones in the coverage area based on the determined location of the occupant; determining a count of the number of occupants in the space based on the movement of the occupants in the coverage area, wherein the plurality of zones include a first zone, a second zone, and a third zone, the first zone including an area outside the space and adjacent to an entry location of the space, the second zone including an area at the entry location, and the third zone including an area inside the space and adjacent to the entry location; determining that the occupant has entered the space in response to determining that the occupant has moved from the first zone through the second zone to the third zone, and determining that the occupant has exited the space in response to determining that the occupant has moved from the third zone through the second zone to the first zone; as well as incrementing the count of the number of occupants in the space when the movement of the occupant indicates that the occupant has moved from a first zone through a second zone to a third zone to enter the space; as well as The count of the number of occupants in the space is decremented when the movement of the occupant indicates that the occupant has moved from the third zone through the second zone to the first zone to exit the space.

22. The occupant detection device of claim 21, wherein the detection circuit comprises a thermopile array and the occupant map comprises a two-dimensional (2D) thermal image of the coverage area.

23. The occupant detection device of claim 22, wherein the thermopile array comprises a plurality of thermal sensitive elements.

24. The occupant detection device of claim 21, wherein the control circuit includes a Kalman tracking filter, the control circuit being configured to use the Kalman tracking filter to determine the coordinates of the occupant in the map.

25. The occupant detection apparatus of claim 21, wherein the control circuit is further configured to determine that the occupant has entered a quiescent state based on a lack of movement of the occupant in the coverage area or in response to a loss of detection of the occupant in the coverage area.

26. The occupant detection device of claim 25, wherein the control circuit is configured to maintain the count of the number of occupants unchanged in response to determining that the occupant has entered the quiescent state.

27. The occupant detection device of claim 21, wherein the detection circuitry includes a visible light sensing circuitry having a camera for generating an occupant map.

28. The occupant detection device of claim 21, wherein the detection circuit comprises radar sensing circuitry.

29. The occupant detection device of claim 21, further comprising a communication circuit, wherein the control circuit is configured to transmit a message indicative of the count of the number of occupants via the communication circuit.

30. The occupant detection device of claim 29, wherein the control circuit is further configured to reset the count of the number of occupants to zero after the message is sent.

31. The occupant detection device of claim 21, further comprising a communication circuit configured to receive a signal from an occupancy sensor indicating an occupancy condition of the space.

32. The occupant detection device of claim 31, wherein the control circuit is further configured to set the count of the number of occupants to zero when the signal received from the occupancy sensor indicates that the space is unoccupied.

33. The occupant detection device of claim 21, wherein the control circuit is further configured to maintain historical data indicative of the count of the number of occupants during various time periods.

34. A method of detecting an occupant entering or exiting a space, the method comprising: receiving one or more signals from a detection circuit; generating an occupant map indicating locations of the occupants; determining the location of the occupant based on coordinates of the occupant in the occupant map; determining movement of the occupant through a plurality of zones of a coverage area based on the determined location of the occupant, wherein the plurality of zones include a first zone, a second zone, and a third zone, the first zone including an area outside the space and adjacent to an entry location of the space, the second zone including an area at the entry location, and the third zone including an area inside the space and adjacent to the entry location; determining that the occupant has entered the space in response to determining that the occupant has moved from the first zone through the second zone to the third zone; as well as The occupant is determined to have exited the space in response to determining that the occupant has moved from the third zone through the second zone to the first zone.

35. The method of claim 34, further comprising: The coordinates of the occupant are determined using a Kalman tracking filter.

36. The method of claim 35, further comprising: determining preliminary coordinates of the occupant in the occupant map based on the one or more signals; as well as The preliminary coordinates are adjusted using the Kalman tracking filter.

37. The method of claim 34, wherein the occupant map comprises a two-dimensional (2D) thermal image of the coverage area generated by a thermopile array having a plurality of thermal elements, and wherein the location of the occupant in the coverage area is indicated in the thermal image.

38. A method as claimed in claim 34, wherein the one or more signals are generated by detection circuits, and the occupant map includes a two-dimensional (2D) image of the coverage area generated by a visible light sensing circuit having a camera, and wherein the position of the occupant in the coverage area is indicated in the image.

39. A method as claimed in claim 34, wherein the one or more signals are generated by detection circuitry, and the occupant map comprises a two-dimensional (2D) occupant map of the coverage area generated by radar sensing circuitry, and wherein the positions of the occupants in the coverage area relative to the multiple zones are indicated in the occupant map.

40. The method of claim 34, further comprising: A determination is made that the occupant has entered a standstill state based on a lack of movement of the occupant or in response to a loss of detection of the occupant.

41. The method of claim 40, further comprising: A determination is made that the occupant has entered the standstill state based on a lack of movement of the occupant during a preconfigured time period.

42. The method of claim 41, further comprising: assigning an identifier to the occupant in response to detecting that the occupant has entered one of the plurality of zones from the standstill state; as well as The movement of the occupant through the plurality of zones is tracked using the identifier.

43. The method of claim 42, further comprising: The occupant is disassociated from the identifier in response to detecting that the occupant has moved from one of the plurality of zones to the standstill state.

44. The method of claim 34, further comprising: maintaining an occupant count of said space; incrementing the occupant count in response to determining that the occupant has entered the space; as well as The occupant count is decremented in response to determining that the occupant has exited the space.

45. The method of claim 44, further comprising: A message indicative of the occupant count is sent via the communication circuit.

46. ​​The method of claim 45, further comprising: After the message is sent, the occupant count is reset to zero.

47. The method of claim 45, further comprising: The message is sent to an external controller.

48. The method of claim 44, further comprising: A signal is received from an occupancy sensor indicative of an occupancy condition of the space.

49. The method of claim 48, further comprising: The occupant count is set to zero when the signal received from the occupancy sensor indicates that the space is unoccupied.

50. The method of claim 44, further comprising: Historical data is maintained indicating corresponding occupant counts of the space during various time periods.

Images