Patent Description:
Tracking of objects, such as material, people and/or equipment, locating or moving inside buildings may be used to monitor flow of the objects inside the buildings. Typically, the object tracking is especially important for construction and renovation sites, where a lot of construction material goes into the building and waste material comes out. For example, understanding the material flow better enables better optimization material flow and synchronization of the material flow to people flow. Typically, the object tracking inside the buildings may be based on indoor positioning solutions, e.g. Wi-Fi or Bluetooth based solutions. The monitoring the material flow and especially monitoring the people flow are important aspects from the viewpoint of an operation of elevator systems arranged inside the buildings for conveying objects between floors of the building.

A <CIT> discloses a method of operating an elevator call control system that may include an indoor positioning system.

An objective of the invention is to present an elevator system and a method for tracking objects. Another objective of the invention is that the elevator system and the method for tracking objects enable monitoring flow of objects inside a building.

The objectives of the invention are reached by an elevator system and a method as defined by the respective independent claims.

According to a first aspect, an elevator system having an object tracking functionality is provided, wherein the elevator system comprises: at least one elevator shaft along which at least one elevator car is configured to travel between a plurality of floors; at least one elevator interface device on each floor (106a-106n) comprising one receiver device of the plurality of receiver devices (110a-110n), wherein the plurality of receiver devices (110a-110n) form a wireless mesh network (<NUM>); a computing unit; at least one gateway device for providing connection between the wireless mesh network and the computing unit; and one or more tag devices, each attached to an object, wherein each of the plurality of receiver devices is configured to: monitor advertisement signals transmitted by the one or more tag devices within an operational range of said receiver device, wherein each advertisement signal comprises an identifier for identifying the tag device transmitting said advertisement signal; and provide device data associated with each detected advertisement signal to the computing unit via the wireless mesh network and the at least one gateway device, wherein the device data comprises signal strength value of the detected advertisement signal and the identifier of the detected advertisement signal, wherein the computing unit is configured to define a location of the object based on the provided device data associated with the tag device attached to said object. The computing unit may be configured to define the location of the object based on the signal strength values comprised in the device data provided by at least three receiver devices.

In a further embodiment, the computing unit may be configured to filter the signal strength values before defining the location of the object.

The device data may further comprise a time stamp indicating a detection time of the advertisement signal, wherein the computing unit may further be configured to define the location of the object at specific one or more instants of time and/or during a specific period of time.

The one or more tag devices may each further comprise one or more sensor devices configured to provide environmental related information about the environment of said tag device, wherein the device data may further comprise the environmental related information.

Each receiver device may be powered by an elevator control bus.

The computing unit may be an elevator control unit or an external computing unit connected to the elevator system via the at least one gateway device. The wireless mesh network may be based on a Bluetooth communication protocol.

According to a second aspect, a method for object tracking with an elevator system having an object tracking functionality is provided, wherein the method comprises: monitoring, by each of a plurality of receiver devices, advertisement signals transmitted, by one or more tag devices each attached to an object, within an operational range of said receiver device, wherein, wherein at least one elevator interface device of the elevator system on each floor comprises one receiver device of the plurality of receiver devices, and wherein each advertisement signal comprises an identifier for identifying the tag device transmitting said advertisement signal; providing, by each of the plurality receiver device, device data associated with each detected advertisement signal to a computing unit via a wireless mesh network formed by the plurality of receiver devices and via at least one gateway device, which provides connection between the wireless communication network and the computing unit, wherein the device data comprises signal strength value of the detected advertisement signal and the identifier of the detected advertisement signal; and defining, by the computing unit, a location of the object based on the provided device data associated with the tag device attached to said object.

The defining of the location of the object may comprise defining the location of the object based on the signal strength values comprised in the device data provided by at least three receiver devices.

In a further embodiment, the method may further comprise filtering the signal strength values before defining the location of the object.

The device data may further comprise a time stamp indicating a detection time of the advertisement signal, wherein the method may further comprise defining, by the computing unit, the location of the object at specific one or more instants of time and/or during a specific period of time.

In a further embodiment, the method may further comprise providing, by one or more sensor devices of the one or more tag devices, environmental related information about the environment of said tag device, wherein the device data may further comprise the environmental related information.

The computing unit may be an elevator control unit or an external computing unit connected to the elevator system via the at least one gateway device.

The wireless mesh network may be based on a Bluetooth communication protocol.

<FIG> illustrates schematically an example of an elevator system <NUM> having an object tracking functionality according to the invention. The object tracking functionality of the elevator system <NUM> enables to monitor flow of the objects <NUM> inside a building in which the elevator system <NUM> resides. The flow of the objects <NUM>, e.g. material, is especially important for construction and renovation sites where a lot of construction material goes into the building and waste comes out. Understanding the material flow better enables better optimization and material flow synchronization to people flow. The elevator system <NUM> comprises at least one elevator shaft <NUM> along which at least one elevator car <NUM> is configured to travel between a plurality of floors, i.e. landings, 106a-106n, a plurality of receiver devices 110a-110n forming a wireless mesh network <NUM>, a computing unit <NUM>, at least one gateway device <NUM> for providing connection between the wireless mesh network <NUM> and the computing unit <NUM>, and one or more tag devices <NUM>. The elevator system <NUM> may further comprise one or more other know elevator related entities, e.g. hoisting machine, elevator control unit, at least one elevator interface device, etc..

Each of the plurality of receiver devices 110a-110n forming the wireless mesh network <NUM> may communicate with each other. The wireless mesh network <NUM> may relay messages by receiver device 110a-110n to receiver device 110a-110n until the message reaches the receiver device 110a-110n to which the message is intended. The messages may comprise data, e.g. device data as will be described later. The wireless mesh network <NUM> may be based on a Bluetooth communication protocol, e.g. Bluetooth low energy (BLE) protocol. The plurality of receiver devices 110a-110n may be Bluetooth receiver devices and the one or more tag devices <NUM> may be Bluetooth tag devices. This means that the communication between the plurality of receiver devices 110a-110n each other and the communication between the plurality of receiver devices 110a-110n and the one or more tag devices <NUM> may be based on the Bluetooth communication protocol. The at least one gateway device <NUM> may be part of the wireless mesh network <NUM>, i.e. the at least one gateway device <NUM> may be a Bluetooth gateway device and the communication between the at least one gateway device <NUM> and the plurality of receiver devices 110a-110n forming the wireless mesh network <NUM> may be based on the Bluetooth communication protocol as illustrated in the example of <FIG>. Alternatively, the at least one gateway device <NUM> may be coupled by a wired connection to at least one of the plurality of receiver devices 110a-110n and the communication between the at least one gateway device <NUM> and the wireless mesh network <NUM> via the at least one of the plurality of receiver devices 110a-110n may be based on one or more known wired communication technologies.

At least one elevator interface device of the elevator system <NUM> on each floor 106a-106n comprises one receiver device of the plurality of receiver devices 110a-110b. In other words, each of the plurality of receiver devices 110a-110n is arranged on each floor 106a-106n inside an elevator interface device. The at least one elevator interface device, e.g. a floor operating panel, a landing call panel or a destination operation panel, is capable of generating elevator calls for driving the at least one elevator car. Each receiver device of the plurality of receiver devices 110a-110n may be powered by an elevator control bus. Arranging the plurality of receiver devices 110a-110n inside the elevator interface devices enables that the plurality of receiver devices 110a-110n may be integrated to the elevator interface devices, which are already existing entities of the elevator system <NUM>, which in turn enables cheaper hardware costs and easy and quick installation of the plurality of receiver devices 110a-110n. The integration of the plurality of receiver devices 110a-110n into the elevator interface devices enables that there is no need to have visible receiver devices on walls and/or ceilings of the building, which may reduce vandalism directed to the receiver devices 110a-110n. For sake of clarity the elevator interface devices are not shown in <FIG>. The plurality of receiver devices 110a-110n may also be already existing receiver devices of the elevator system <NUM> configured to receive one or more radio signals transmitted by one or more wireless devices, e.g. wireless elevator call buttons.

Each of the one or more tag devices <NUM> is attached to, i.e. carried by, an object <NUM> to be tracked. The objects <NUM> may e.g. be material, a people, and/or equipment. The one or more tag device <NUM> may also be any device equipped with a wireless transmitter unit, e.g. a Bluetooth transmitter unit. The one or more tag devices <NUM> may also be integrated to a tool; a wearable device; such as a helmet, watch, etc., a mobile terminal device; etc.; carried by people to be tracked. The objects <NUM> to be tracked may locate or move inside the building. Each tag device <NUM> is configured to transmit advertisement signals, i.e. radio signals, at regular intervals, e.g. every few seconds. Each advertisement signal comprises at least an identifier, e.g. a unique ID, for identifying the tag device <NUM> transmitting said advertisement signal.

The computing unit <NUM> may be an elevator control unit or an external computing unit connected to the elevator system <NUM> via the at least one gateway device <NUM> as shown in the example of <FIG>. The external entity herein means an entity that locates separate from elevator system <NUM>. The computing unit <NUM> is communicatively coupled to the at least one gateway device <NUM>. The communication between the computing unit <NUM> and the at least one gateway device <NUM> may be based on one or more known communication technologies, either wired or wireless, e.g. cellular communication technology. The implementation of the computing unit <NUM> may be done as a stand-alone computing entity or as a distributed computing environment between a plurality of stand-alone computing entities, such as a plurality of servers providing distributed computing resource.

The plurality of receiver devices 110a-110n is configured to monitor the advertisement signals transmitted by the one or more tag devices <NUM> within an operational range, i.e. radio range, of said receiver device 110a-110n. The plurality of receiver devices 110a-110n is further configured to provide the device data associated with each detected advertisement signal to the computing unit <NUM> via the wireless mesh network <NUM> and the at least one gateway device <NUM>. In other words, each receiver device of the plurality of receiver devices 110a-110b is configured to provide the device data of each detected advertisement signal first to the at least one gateway device <NUM> via the wireless mesh network <NUM> and the at least one gateway device <NUM> then provides the device data to the computing unit <NUM>. The device data comprises signal strength value of the detected, i.e. received, advertisement signal and the identifier of the detected advertisement signal. The signal strength value may be defined, by the receiving receiver device 110a-110n, based on a Received Signal Strength Indicator (RSSI) value.

The computing unit <NUM> is configured to define, i.e. estimate, a location of the object <NUM> based on the provided device data associated with the tag device <NUM> attached to said object <NUM>. The computing unit <NUM> may be configured to define the location of the object <NUM> to which the tag device <NUM> is attached based on the signal strength values comprised in the device data provided by at least three receiver devices 110a-110n of the plurality of receiver devices 110a-110n. In other words, at least three receiver devices 110a-110n receives the advertisement signal transmitted by the tag device <NUM> attached to the object <NUM> and the at least three receiver devices 110a-110n provides to the computing unit <NUM> via the wireless mesh network <NUM> and the at least one gateway device <NUM> the device data comprising the received signal strength value of said advertisement signal from the tag device <NUM> attached to the object <NUM>. The computing unit <NUM> may be configured to define the location of the object <NUM> to which the tag device <NUM> is attached based on the signal strength values of said advertisement signal from the tag device <NUM> provided by the at least three receiver devices 110a-110n.

The signal strength value of the advertisement signal attenuates relative to distance, if there are no obstacles, e.g. walls, ceilings, floors, and/or people, on a signal path of the advertisement signal. However, the obstacles on the signal path may cause additional attenuation to the signal strength value. Alternatively or in addition, reflections of the signal may have an effect on the signal strength value. Alternatively or in addition, a position of an antenna of the tag device <NUM> may cause variation to the signal strength value.

According to an exemplifying embodiment of the invention, the computing unit <NUM> may be configured to compare the signal strength values of the advertisement signal from the tag device <NUM> received by the at least three receiver devices 110a-110n to define the location of the tag device <NUM>, i.e. the floor 106a-106n where the tag device <NUM> locates. This enables that the attenuation caused by the stationary obstacles e.g. walls, ceilings, and/or floors, on the signal path may be taken into account in the definition of the location of the object <NUM>. This enables that location of the object <NUM> to which the tag device <NUM> is attached may be defined with the accuracy of the floor 106a-106n, i.e. the floor 106a-106n, where the object <NUM> locates may be defined. For example, in the example of <FIG>, the receiver device 110d at the floor 106d receives an advertisement signal transmitted by the tag device <NUM> with -<NUM> dBm signal strength, the receiver 110n at the floor 106n does not receive the advertisement signal transmitted by the tag device <NUM>, the receiver device 110c at the floor 106c receives the advertisement signal transmitted by the tag device <NUM> with -<NUM> dBm signal strength, and the receiver device 110b at the floor 106b receives the advertisement signal transmitted by the tag device <NUM> with -<NUM> dBm signal strength. Based on the above information, i.e. device data received from the receiver devices 110b-110n, the computing unit <NUM> may define that the tag <NUM> attached to the object <NUM> locates at the floor 106c.

Alternatively or in addition, according to an exemplifying embodiment of the invention, the computing unit <NUM> may be configured to apply one or more intelligent algorithms, e.g. one or more machine learning algorithms, preferably together with historical device data gathered from the plurality of receiver devices 110a-110n over a longer period of time in order to define the location of the object <NUM> to which the tag device <NUM> is attached. The historical device data may be used as a training data to train the one or more intelligent algorithms. This improves the accuracy of the definition of the location of the tag device <NUM>, which in turn enables that the location of the object <NUM> to which the tag device <NUM> is attached may be defined more accurately in addition to the definition of the floor 106a-106n, where the object <NUM> locates, e.g. more accurate location of the object <NUM> on said floor 106a-106n may be defined.

Alternatively or in addition, according to an exemplifying embodiment of the invention, the computing unit <NUM> may first be configured to define, i.e. estimate, an estimate distance between the tag device <NUM> attached to said object <NUM> and each receiver device 110a-110n from which the device data associated with the tag device <NUM> attached to said object <NUM> is provided based on the signal strength value comprised in the device data. The computing unit <NUM> may then be configured to define the location of the object <NUM> based on the defined estimate distances between the tag device <NUM> attached to said object <NUM> and at least three receiver devices 110a-110n from which the device data associated with the tag device <NUM> attached to said object <NUM> is provided. The computing unit <NUM> may use triangulation to define the location of the object <NUM> based on the defined distances between the tag device <NUM> attached to said object <NUM> and at least three receiver devices 110a-110n.

Alternatively or in addition, according to an exemplifying embodiment of the invention, the computing unit <NUM> may be configured to filter the received signal strength values before defining the location of the object <NUM> to reduce the variation of the signal strength value caused by movement of the tag device <NUM> attached to the object <NUM>, the position of the antenna of the tag device <NUM>, and/or moving obstacles, e.g. people. The filtering may for example be, but is not limited to, Kalman filtering.

According to an exemplifying embodiment of the invention, the device data may further comprise a time stamp indicating a detection time of the advertisement signal. This enables that the computing unit <NUM> may further be configured to define the location of the object <NUM> at specific one or more instants of time and/or during a specific period of time based on the time stamps comprised in the device data. This provides further information for monitoring the flow of the objects <NUM> inside the building in which the elevator system <NUM> resides.

Alternatively or in addition, according to an exemplifying embodiment of the invention, the one or more tag devices <NUM> may each further comprise one or more sensor devices configured to provide environmental related information, e.g. temperature, humidity, etc., about the environment of said tag device <NUM>. The device data may further comprise the environmental related information. This provides further information for monitoring the flow of the objects <NUM> inside the building in which the elevator system <NUM> resides.

Next an example of the method for object tracking with the elevator system <NUM> having the object tracking functionality according to the invention is described by referring to <FIG> schematically illustrates the invention as a flow chart.

At a step <NUM>, each of the plurality of receiver devices 110a-110n monitors the advertisement signals transmitted by the one or more tag devices <NUM> within an operational range, i.e. radio range, of said receiver device 110a-110n. Each tag device <NUM> transmits advertisement signals, i.e. radio signals, at regular intervals, e.g. every few seconds. Each advertisement signal comprises an identifier for identifying the tag device <NUM> transmitting said advertisement signal.

At a step <NUM>, each of the plurality of receiver devices 110a-110n further provides device data associated with each detected advertisement signal to the computing unit <NUM> via the wireless mesh network <NUM> and the at least one gateway device <NUM>. In other words, each receiver device of the plurality of receiver device 110a-110b provides the device data of each detected advertisement signal first to the at least one gateway device <NUM> via the wireless mesh network <NUM> and the at least one gateway device <NUM> then provides the device data to the computing unit <NUM>. The device data comprises signal strength value of the detected, i.e. received, advertisement signal and the identifier of the detected advertisement signal. The signal strength value may be defined, by the receiving receiver device 110a-110n, based on a Received Signal Strength Indicator (RSSI) value. The computing unit <NUM> receives the device data from the plurality of receiver devices.

At a step <NUM>, the computing unit defines, i.e. estimates, a location of the object <NUM> based on the provided device data associated with the tag device <NUM> attached to said object <NUM>. The computing unit <NUM> may define the location of the object <NUM> to which the tag device <NUM> is attached based on the signal strength values comprised in the device data provided by at least three receiver devices 110a-110n of the plurality of receiver devices 110a-110n. In other words, at least three receiver devices 110a-110n receives the advertisement signal transmitted by the tag device <NUM> attached to the object <NUM> and the at least three receiver devices 110a-110n provides to the computing unit <NUM> via the wireless mesh network <NUM> and the at least one gateway device <NUM> the device data comprising the received signal strength value of said advertisement signal from the tag device <NUM> attached to the object <NUM>. The computing unit <NUM> may define the location of the object <NUM> to which the tag device <NUM> is attached based on the signal strength values of said advertisement signal from the tag device <NUM> provided by the at least three receiver devices 110a-110n.

According to an exemplifying embodiment of the invention, at the step <NUM> the computing unit <NUM> may compare the signal strength values of the advertisement signal from the tag device <NUM> received by the at least three receiver devices 110a-110n to define the location of the tag device <NUM>, i.e. the floor 106a-106n where the tag device <NUM> locates. This enables that the attenuation caused by the stationary obstacles e.g. walls, ceilings, and/or floors, on the signal path may be taken into account in the definition of the location of the object <NUM>. This enables that location of the object <NUM> to which the tag device <NUM> is attached may be defined with the accuracy of the floor 106a-106n, i.e. the floor 106a-106n, where the object <NUM> locates may be defined.

Alternatively or in addition, according to an exemplifying embodiment of the invention, at the step <NUM> the computing unit <NUM> may apply one or more intelligent algorithms, e.g. one or more machine learning algorithms, preferably together with historical device data gathered from the plurality of receiver devices 110a-110n over a longer period of time in order to define the location of the object <NUM> to which the tag device <NUM> is attached. The historical device data may be used as a training data to train the one or more intelligent algorithms. This improves the accuracy of the definition of the location of the tag device <NUM>, which in turn enables that the location of the object <NUM> to which the tag device <NUM> is attached may be defined more accurately in addition to the definition of the floor 106a-106n, where the object <NUM> locates, e.g. more accurate location of the object <NUM> on said floor 106a-106n may be defined.

Alternatively or in addition, according to an exemplifying embodiment of the invention, at the step <NUM> the computing unit <NUM> may first define, i.e. estimate, an estimate distance between the tag device <NUM> attached to said object <NUM> and each receiver device 110a-110n from which the device data associated with the tag device <NUM> attached to said object <NUM> is provided based on the signal strength value comprised in the device data. The computing unit <NUM> may then define the location of the object <NUM> based on the defined estimate distances between the tag device <NUM> attached to said object <NUM> and at least three receiver devices 110a-110n from which the device data associated with the tag device <NUM> attached to said object <NUM> is provided. The computing unit <NUM> may use triangulation to define the location of the object <NUM> based on the defined distances between the tag device <NUM> attached to said object <NUM> and at least three receiver devices 110a-110n.

Alternatively or in addition, according to an exemplifying embodiment of the invention, at the step <NUM> the computing unit <NUM> may filter the received signal strength values before defining the location of the object <NUM> to reduce the variation of the signal strength value caused by movement of the tag device <NUM> attached to the object <NUM>, the position of the antenna of the tag device <NUM>, and/or moving obstacles, e.g. people. The filtering may for example be, but is not limited to, Kalman filtering.

According to an exemplifying embodiment of the invention, the device data may further comprise a time stamp indicating a detection time of the advertisement signal. This enables that the computing unit <NUM> may further define at the step <NUM> the location of the object <NUM> at specific one or more instants of time and/or during a specific period of time based on the time stamps comprised in the device data. This provides further information for monitoring the flow of the objects <NUM> inside the building in which the elevator system <NUM> resides.

Alternatively or in addition, according to an exemplifying embodiment of the invention, one or more sensor devices of the one or more tag devices <NUM> may provide environmental related information, e.g. temperature, humidity, etc., about the environment of said tag device <NUM>. The device data may further comprise the environmental related information. This provides further information for monitoring the flow of the objects <NUM> inside the building in which the elevator system <NUM> resides.

<FIG> schematically illustrates an example of components of the computing unit <NUM> according to the invention. The computing unit <NUM> may comprise a processing unit <NUM> comprising one or more processors, a memory unit <NUM> comprising one or more memories, a communication unit <NUM> comprising one or more communication devices, and possibly a user interface (UI) unit <NUM>. The memory unit <NUM> may store portions of computer program code <NUM> and any other data, and the processing unit <NUM> may cause the computing unit <NUM> to operate as described by executing at least some portions of the computer program code <NUM> stored in the memory unit <NUM>. The communication unit <NUM> may be based on at least one known communication technologies, either wired or wireless, in order to exchange pieces of information as described earlier. The communication unit <NUM> provides an interface for communication with any external unit, such as the at least one gateway device <NUM>, database and/or any external entities or systems. The communication unit <NUM> may comprise one or more communication devices, e.g. radio transceiver, antenna, etc. The user interface <NUM> may comprise I/O devices, such as buttons, keyboard, touch screen, microphone, loudspeaker, display and so on, for receiving input and outputting information. The computer program <NUM> may be stored in a non-statutory tangible computer readable medium, e.g. an USB stick or a CD-ROM disc.

Claim 1:
An elevator system (<NUM>) having an object tracking functionality, the elevator system (<NUM>) comprising:
at least one elevator shaft (<NUM>) along which at least one elevator car (<NUM>) is configured to travel between a plurality of floors (106a-106n),
at least one elevator interface device on each floor (106a-106n) comprising one receiver device of a plurality of receiver devices (110a-110n), wherein the plurality of receiver devices (110a-110n) form a wireless mesh network (<NUM>),
a computing unit (<NUM>),
at least one gateway device (<NUM>) for providing connection between the wireless mesh network (<NUM>) and the computing unit (<NUM>), and
one or more tag devices (<NUM>), each attached to an object (<NUM>),
wherein each of the plurality of receiver devices (110a-110n) is configured to:
monitor advertisement signals transmitted by the one or more tag devices (<NUM>) within an operational range of said receiver device (110a-110n), wherein each advertisement signal comprises an identifier for identifying the tag device (<NUM>) transmitting said advertisement signal, and
provide device data associated with each detected advertisement signal to the computing unit (<NUM>) via the wireless mesh network (<NUM>) and the at least one gateway device (<NUM>), wherein the device data comprises signal strength value of the detected advertisement signal and the identifier of the detected advertisement signal,
wherein the computing unit (<NUM>) is configured to define a location of the object (<NUM>) based on the provided device data associated with the tag device (<NUM>) attached to said object (<NUM>).