A networked system having a control device and a plurality of controlled devices, as well as a device and method used by the system

Abstract

A networked system has a first device that sends commands to one or more other devices. These other devices suppress their own status reporting if they are able to comply with the command. Thus, network status data is maintained based on the commands unless the status reports indicate that the command could not be complied with or that a state change was made in response to the command from the first device.

Description

Technical Field

[0001] The present invention relates to a networked system having a control device and a plurality of controlled devices. The present invention also relates to devices and methods used by the system.

Background Art

[0002] The present invention is generally interested in networks of devices, but in particular has a specific application to networked lighting systems.

[0003] In the professional lighting market, there is a shift towards connected lighting systems that enable the implementation of all kinds of new features. These new features include, for example, remote scheduling, energy monitoring, sensor-based lighting control, asset management, etc.

[0004] To reduce the amount of wiring in installations, local area wireless communication is rapidly spreading as a means of transmitting lighting commands to each node and evaluating the state of each luminaire.

[0005] Examples of such wireless network protocols currently widely used include various proprietary network implementations built on top of the IEEE 802.15.4, 802.15.1 or 802.11* standards, and open standards such as ZigBee®, Thread, BLE Mesh, Wi-Fi®.

[0006] In some cases, these systems can consist of many wireless nodes and careful network design is necessary to avoid messages being lost due to collisions between network packets.

[0007] Since packet collisions cannot be completely avoided, most of these network protocols have a retry mechanism for cases where a packet does not reach its destination (and / or the acknowledgment response does not return to the command issuer).

[0008] Often, the network is very large (in terms of distance) so that the central controller cannot reach all nodes directly. Therefore, some network protocols implement a mechanism to send messages via other nodes. In this way, a remote node can also be reached via one or more "hops".

[0009] Messages that require many hops need to be resent many times by network packets to reach the destination node, resulting in extra traffic on the network.

[0010] This leads to a situation where sending commands from the central controller to many nodes (or receiving information from many nodes by the central controller) requires a clever way to avoid packet collisions.

[0011] US2018 / 0027631 A1 relates to a monitor lighting control device that receives a status change event message including (i) a status change event, such as an event reported by an occupancy sensor or an on / off switch, (ii) an identifier of a member lighting control device that detected the event, and (iii) a control group identifier of a lighting control group including the monitor lighting control device and members of the lighting control device. The monitor lighting control device sends an acknowledgment response to the member lighting control device and then sends a multicast message including the status change event to the lighting control group. To process multiple simultaneous group / zone status change requests, when the monitor lighting control device receives a new status change, it checks whether the change is in progress. If so, it cancels the status change and executes the new status change.

[0012] US2019 / 008024 A1 relates to a method of pairing an access device and a lighting fixture. For this purpose, the access device broadcasts a first command, and in response, the lighting fixture transmits first information including its own lighting fixture identifier and radio wave intensity to the access device. The access device transfers its own identifier and a part of the first information to the lighting controller. When it is determined that a predetermined lighting fixture has transmitted the first information only to one access device, the lighting controller pairs the predetermined lighting fixture and the one access device. When it is determined that a predetermined lighting fixture has transmitted the first information to a plurality of access devices, the lighting controller determines to pair the access device with the strongest radio wave intensity among the plurality of access devices and the predetermined lighting fixture.

[0013] When transmitting a lighting control command, broadcasting is an efficient way to send control messages to a large number of nodes. Broadcast messages can be received simultaneously by many nodes, and if each node repeats the message several times, the possibility of missing the command becomes low enough to be acceptable. Depending on the size and density of the network, the number of repetitions can be configured (in some networks) to suppress the "network storm" that occurs during broadcasting. Without such suppression, each node typically retransmits the message once, which means that one broadcast message in a network of 200 nodes can result in 200 RF transmissions if such suppression is not applied.

[0014] Therefore, it is possible to easily transmit commands from the central controller to the lighting control nodes even in a network consisting of a large number of nodes. However, in the reverse case, difficulties arise. For example, when it is desired to check the status (on / off state, dimming state, color point, energy consumption, error state) of each network device, for example, a lighting fixture, unicast messages must be sent from the central controller to each node, and a response containing the requested data must be sent back towards the controller. If a node is outside the direct communication range from the controller, as a result, a large number of network messages will go up and down. When the network size is large (in terms of distance), this means that the status of each node can only be queried at large intervals, which may not be sufficient for current applications. Summary of the Invention Problems to be Solved by the Invention

[0015] The present invention is directed, in particular, to the problem of minimizing traffic related to status reporting of nodes in response to changes in the state of the nodes, which occurs when there is a large network having a control device (which may be a central controller or simply a device that performs a control role at that time). Means for Solving the Problems

[0016] The present invention is defined by the claims.

[0017] According to an example according to one aspect of the present invention, a first device that executes a control function, a status monitoring device, a plurality of controlled devices, a networked system comprising: The first device is configured to send a control command to the device to be controlled, and the device to be controlled is configured to send a status report message to the status monitoring device. Each device to be controlled includes a device-to-be-controlled receiver for receiving a control command, a device-to-be-controlled transmitter, and a device-to-be-controlled processor. The device-to-be-controlled processor receives a control command for changing the device state from the first device or from another source of the command. If the device to be controlled can adhere to the control command, it changes the device state in response to the control command. determines whether the control command was transmitted from the first device. If the control command was transmitted from the first device and was adhered to, it suppresses the transmission of the status report message to the status monitoring device, and if the control command was not transmitted from the first device, it sends a status report message to the status monitoring device. A device to be controlled is provided that is configured as such.

[0018] Note that the first device may be co-located with the status monitoring device in a centralized unit. That is, the centralized unit may issue control commands and monitor the status of the devices on the network. The centralized unit may be, for example, a network controller.

[0019] The controlled device of this networked system sends a status report message when it changes its state in response to a received command or other events such as switching on the main power supply and / or the local control unit. This is known as attribute reporting. However, when the controlled device correctly changes its state in response to a command from the first device, no status update is given. This reduces the amount of status reporting, thereby reducing data traffic.

[0020] The controlled device processor further, if the control command is sent from the first device and not complied with, sends a status report message, or suppresses the sending of a status report message only if the control command was not complied with but was not complied with by a margin below a threshold, and sends a status report message otherwise. may be configured as such.

[0021] Even if the command is sent from the first device, if the command could not be complied with, a status report message is sent. For example, the controlled device may not have the capability to comply with (partially or fully) the control command. Thus, the status report is sent to ensure that the status monitoring device is aware that the command was not (partially or fully) followed. If the command was not complied with but is a trivial discrepancy (e.g., rounding error or quantization error or a predetermined threshold, etc.), the status report may be suppressed.

[0022] For example, the first device includes a first device transmitter for transmitting control commands and a first device processor for controlling the first device transmitter. The status monitoring device includes a monitoring device receiver for receiving status report messages, a memory for storing network status data, and a monitoring device processor configured to maintain the network status data based on the control commands and the received status report messages.

[0023] If the first (control) device and the status monitoring device are not collocated in one unit, the status monitoring device needs to know what control commands are being transmitted by sniffing the commands (e.g., Zigbee) sent to the device under control or by receiving the control commands (via Zigbee or out-of-band). Thus, the status monitoring device can update the network status data even when reports are not received from the device under control. This knowledge is all based on the control commands.

[0024] The status monitoring device assumes that the commands (from the first device) are complied with, and thus the status monitoring device updates network status data, e.g., a table, until the status report message indicates otherwise. The status report message overrides the assumed value. This can speed up the update of the status report data, which would otherwise require polling with associated delays.

[0025] The monitoring device processor is configured to populate the network status data with static values and a transition function indicating the temporal transition of the values, and the device under control processor may be configured to generate a status report message indicating the static values and optionally also the transition function.

[0026] This measure avoids the need for repeated reporting of state changes that follow a known evolution over time ("dead reckoning"). The state report may be provided, for example, at the end of a time transition (if no command is being transmitted from the first device). An alternative or additional example is to extend the reporting mechanism with a report that shows not only the current value, but also the transition end value and the (remaining) transition time.

[0027] The state report may, for example, include the identification of a transient function if the function is not yet known to the state monitoring device (e.g., not set by the state monitoring device). For example, if the controlled device processor is implementing a dimming curve known to the state monitoring device, it may be sufficient for the controlled device processor to report the current state, whereby the monitoring device processor will be able to determine the function being followed.

[0028] The first device processor or the state monitoring device may be configured to periodically poll the controlled device for state checks. The results of the polling (even if transmitted from the first device) will need to be sent to the state monitoring device.

[0029] Thus, the controlled device can not only report immediately in response to a state change, but also report periodically based on periodic polling. Polling provides, for example, a safety net against missing a reporting message.

[0030] For example, an overrule bit or flag may be used to enable and disable the approach of the present invention so that instead conventional attribute reporting can be used to avoid a mismatch between the actual state and the managed state.

[0031] The system includes a networked lighting system, the device to be controlled includes lighting fixtures, and the control commands may include on / off commands, brightness level commands, color temperature commands, color setting commands, and one or more of the above.

[0032] This is one preferred application of a networked system. There are also other applications such as heating, ventilation, and air conditioning systems (HVAC), traffic lighting systems, systems including a network of sensor nodes, etc.

[0033] The present invention also relates to a device to be controlled for use in a network and controlled by a first device of the network that executes a control function, the device to be controlled including a device-to-be-controlled receiver for receiving control commands from the first device, a device-to-be-controlled transmitter, and a device-to-be-controlled processor, the device-to-be-controlled processor receives control commands for changing the device state from the first device or from another source of control commands, when the device to be controlled can comply with the control commands, changes the device state in response to the control commands, determines whether the control commands are transmitted from the first device, when the control commands are transmitted from the first device and are complied with, suppresses the transmission of a status report message to a status monitoring device, and when the control commands are not transmitted from the first device, transmits a status report message to a status monitoring device, and is configured as such to provide a device to be controlled.

[0034] This controlled device suppresses status report messages when they are not required, because the status is already known (e.g., indicated) by the device that would send the status report message. When the control device is collocated with a status monitoring device, e.g., in a central unit, the status monitoring function of the central unit knows the control commands from the control function of the central unit through some internal interface. Otherwise, the status monitoring device needs to know the control commands.

[0035] For example, the controlled device processor may further send a status report message if the control command is sent from a first device and not complied with, or suppress sending the status report message only if the control command sent from the first device is not complied with but is not complied with by a margin below a threshold, and send the status report message otherwise. It is configured as such.

[0036] In this way, the status report message may also be suppressed when the status is sufficiently close to the state expected by the first device.

[0037] The present invention also provides a control and monitoring device for a networked system, the control and monitoring device being a first device of the networked system that executes a control function, the first device including a first device transmitter for transmitting a control command to a controlled device of the network, a state monitoring device of the networked system that is collocated with the first device for monitoring a state change of the controlled device of the networked system, the state monitoring device including a monitoring device receiver for receiving a state report message, a monitoring device processor, and a memory for storing network state data, the monitoring device receiver being configured to receive, from the controlled device, a state report message indicating that the controlled device has changed its state in response to a control command not transmitted by the first device, or that the controlled device has not complied with a control command transmitted by the first device, the monitoring device processor being configured to adapt the network state data of the controlled device based on the control command transmitted to the controlled device by the first device, assuming compliance by the controlled device, when the control command is transmitted to the controlled device by the first device, to adapt the network state data of the controlled device according to the received state report message when the state report message indicates that the control command transmitted to the controlled device by the first device could not be complied with by the controlled device, and to adapt the network state data of the controlled device according to the received state report message when the state report message indicates that the controlled device has changed its state in response to a control command not transmitted by the first device, so as to maintain the network state data.

[0038] The control and monitoring device is, for example, an illumination system controller.

[0039] The present invention also relates to a network control method for a controlled device for use in a networked system including a first device that executes a control function, a state monitoring device, and a plurality of controlled devices, wherein the first device is configured to send a control command to the controlled device, the controlled device is configured to send a status report message to the state monitoring device, and the method comprises, at the controlled device, receiving a control command for changing the device state; changing the device state in response to the control command if the controlled device can comply with the control command; determining whether the control command was sent from the first device; if the control command was sent from the first device and was complied with, suppressing the transmission of the status report message to the state monitoring device; if the control command was not sent from the first device, sending a status report message to the state monitoring device. A method is provided that includes the above steps.

[0040] This defines a method implemented by the controlled device in which the status report message is suppressed to reduce the amount of data traffic.

[0041] The present invention also relates to a network control method for a control and monitoring device for use in a networked system, wherein the lighting system controller includes a first device that transmits a control command to a controlled device of the network, and a status monitoring device collocated with the first device, and the method includes: the first device transmitting a control command to a controlled device of the network; the status monitoring device storing network status data; receiving the control command transmitted to the controlled device; maintaining the network status data based on the control command; receiving a network status report message; and updating the network status data based on the received network status report message, wherein maintaining includes adapting the network status data of the controlled device based on the control command transmitted to the controlled device, assuming compliance by the controlled device, when the control command is transmitted to the controlled device by the first device, and updating includes adapting the network status data of the controlled device according to the received status report message when the status report message indicates that the control command transmitted by the first device could not be complied with by the controlled device, and adapting the network status data of the controlled device according to the received status report message when the status report message indicates that the controlled device has changed its state in response to a control command not transmitted by the first device, and provides a method.

[0042] This defines a method implemented by a control and monitoring device that transmits and thus receives status report messages only in certain situations in order to reduce data traffic volume. Network status data is updated by default according to control commands, and when the network status is updated, a status report message is received. Updates are made for both control commands and subsequent incoming status report messages. Thus, network status data is maintained based on control commands regardless of whether a status report message is received, and if a status report message is received, the network status data may be (further) updated.

[0043] In these methods as well, the networked system is a lighting system, the device to be controlled is a lighting fixture, and the control commands are on / off commands, brightness level commands, color temperature commands, color setting commands, and may include one or more of these.

[0044] In these methods, a first (commanding) device is collocated with a status monitoring device in a single unit or device such as a network controller, thus representing a control and monitoring device.

[0045] The present invention also provides a computer program including computer program code means configured to implement the above method when the computer program is executed on a computer.

[0046] The present invention also provides a data carrier carrying the computer program.

[0047] These and other aspects of the present invention will become apparent and be elucidated with reference to the embodiments described below.

Brief Description of the Drawings

[0048] For a better understanding of the present invention and to more clearly show how the present invention can be implemented, by way of example only, the accompanying drawings are referred to.

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0049] The present invention will be described with reference to the drawings.

[0050] It should be understood that the detailed description and specific examples are illustrative of exemplary embodiments of the apparatus, system and method, but are for illustrative purposes only and are not intended to limit the scope of the present invention. These and other features, aspects and advantages of the apparatus, system and method of the present invention will be better understood from the following description, the appended claims and the accompanying drawings. It should be understood that the drawings are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the drawings to indicate the same or similar parts.

[0051] The present invention provides a networked system having a first device that sends commands to one or more other devices. These other devices suppress reporting of their status if they can comply with the commands. Thus, network state data is maintained based on the commands unless the status report indicates that the command could not be complied with or that a state change was made without responding to the command from the first device.

[0052] The present invention provides a modification to the conventional attribute reporting scheme. Zigbee (registered trademark) defines attribute reporting in which devices are configured to report changes in attributes. This is used, for example, in sensors where a light level sensor is instructed to report the last measured value when there is a change exceeding a set amount or periodically (e.g., every 5 minutes). To prevent network overload when values change rapidly, limits may be provided on the reporting frequency, for example, no more than once every 5 seconds.

[0053] In the case of lighting, the relevant attributes may be the on / off state, brightness, color, etc., which would be composed of a set of similar parameters.

[0054] When a network controller sends commands (e.g., "switch on", "increase brightness to 75%", etc.) to set one or more of these parameters, and the lighting fixtures are configured with conventional attribute reporting, the lighting fixtures all respond to the network controller and report that they have actually executed this change.

[0055] This is effective for the controller to confirm that each device has actually received (and processed) the command, but it results in a large number of network messages. Also, the fact that all lighting fixtures may try to send such reporting messages simultaneously places stress on the communication algorithm (CSMA-CD). Thus, when many lighting fixtures are involved, it may happen that not all reports are actually delivered. In this case, the controller may erroneously assume that these lighting fixtures did not receive the control message, even though in fact some of the lighting fixtures received the control message but their reports did not arrive. A scheduling mechanism may be used to solve this problem.

[0056] In existing lighting systems, instead, it is known that a network controller periodically polls lighting fixtures to determine their status. The main purpose is to maintain a view of the status in a database of all lighting fixtures in the network. This may be used by a reporting application to represent the current state of the lights, or by the controller itself (e.g., rules that trigger only when there are specific user commands and specific lighting fixture settings). This polling is executed in a round-robin phase (e.g., polling one lighting fixture every 2 seconds). Thus, in a large-scale system (e.g., 60 lighting fixtures), this takes 120 seconds for a full cycle, and the delay from a change in the lighting fixture to its reflection in the database is on average 60 seconds.

[0057] Part of this delay is addressed by directly storing the result of a specific command (e.g., when sending a scene recall) in the database and assuming that the lighting fixture will operate accordingly. In this case, the main purpose of polling is to track light transitions not triggered by the network controller itself, such as on / off of the main power supply, control by Bluetooth Low Energy or the proxy approach used in commercial lighting networks, other Zigbee® controllers that can send lighting fixture commands not recognized by the network controller, control by sensors, switches, devices that send scheduled commands (e.g., turning on lights at sunset or near sunset), etc. In the case of the proxy approach, a device such as a smartphone can connect to one of the lights (which is the proxy) via Bluetooth Low Energy®, BLE, and the control command is transmitted from the proxy to other lights (controlled devices) via Zigbee®.

[0058] In addition, there are lighting control commands sent by the network controller that are not reflected in the database due to their transient nature. A typical example of this is the "entertainment" (streaming) function in which the network controller repeatedly sends commands to change the light intensity and / or color to a large number of luminaires at high speed (e.g., 10 times per second). It is not important to update such changes in the database because they are invalidated immediately afterwards (by the next command sent).

[0059] Regarding the sources of all these lighting changes, the latency due to the polling cycle is not resolved.

[0060] Using attribute reporting instead of (or in addition to) polling can address some of these issues. For example, in the case of attribute reporting, all luminaires immediately send all changes to the network controller. Thus, the database can be updated immediately. Generally, the network is designed such that message transmission is highly reliable. Therefore, reporting all light state changes can be considered a waste of valuable resources (network bandwidth) for messages for which the network controller already knows that the luminaire has changed its state (because the network controller instructed the luminaire to do so). This applies to most of the state changes of luminaires in a networked lighting system (most changes are instructed by the network controller).

[0061] Thus, the present invention may be considered to provide an adaptation to attribute reporting.

[0062] FIG. 1 shows a networked system 10 that includes a first device 12 that executes a control function. This may be a central network controller, but equally all devices on the network are the same and one may execute an instructing function at a particular instant.

[0063] There are a plurality of controlled devices 14, 16, 18.

[0064] The first device 12 sends a control command to the controlled device, and the controlled device returns a status report message to the first device.

[0065] This example is based on the device that sends the command being the same as the device that receives the status report for simplicity of explanation. However, there may be a separate status monitoring device that receives the status report message. Thus, there may be a separate first device (that can send commands) and a separate status monitoring device (that monitors the network status). Also, the status monitoring device will receive the control command so as to know the control command that was sent. Some system adaptation may be required so that these messages are not filtered. For example, the system may be configured to interpret all network traffic that it can hear to infer the status of lighting fixtures. In the case of Zigbee broadcast / multicast / groupcast, messages are always received (at the physical level). In the case of unicast, messages are not always received at the physical level.

[0066] Communication between the control function and the monitoring function may be outside the band (e.g., an Ethernet (registered trademark) or Wi-Fi (registered trademark) network within a building), or may be via a cloud connection. When such out-of-band communication is used, if its latency is large, the control command may arrive at the status monitoring device (at short time intervals) after the status report message from the controlled device has arrived. In this case, since the status report message from the controlled device is likely to represent the status better, it may be better to ignore the out-of-band control command.

[0067] In this example, the first device and the status monitoring device are the same device. In particular, both are an integral part of the network controller.

[0068] Each controlled device includes a controlled device transceiver 20 having a controlled device receiver and a controlled device transmitter for receiving control commands, and a controlled device processor 22.

[0069] The controlled device has a functional unit such as a lighting unit. In this case, each controlled device is a lighting fixture in a lighting fixture network, and the first device is a lighting system controller (which may be known as a bridge in, for example, a Philips (registered trademark) Hue (registered trademark) lighting system in some cases).

[0070] Thus, this example is based on a networked lighting system. In this case, the control command is an on / off command, a brightness level command, a color temperature command, a color setting command, and includes one or more of the above.

[0071] This is one preferred application of a networked system. There are also other applications such as home automation, heating, ventilation and air conditioning systems (HVAC), traffic lighting systems, systems including a network of sensor nodes, etc.

[0072] The detailed operation of the system will be described with reference to an example of lighting.

[0073] Each controlled device processor 22 receives a control command for changing the device state from the first device 12 or from another source of the command, and this other source may be another one of the devices, an external source of the command, or even a direct user interaction with the device.

[0074] If the controlled device can comply with the command, the controlled device processor changes the device state in response to the control command (for example, changes the brightness, color, or other output characteristics).

[0075] The controlled device processor determines whether the control command was sent from the first device 12. In the situation where the control function and the monitoring function are separated, of course, it is determined that it comes from the control device rather than the monitoring device.

[0076] If the control command is sent from the first device and is complied with, the transmission of the status report message to the first device (or the status monitoring device if it is a separate device) is suppressed. This is a modification to the conventional attribute reporting approach.

[0077] If the control command is not sent from the first device, the status report message is sent to the first device (or the status monitoring device if it is a separate device).

[0078] In this way, when the device under control changes its state in response to a received command that did not come from the first device, or to other events such as switching on the main power supply and / or the local control unit, it sends a status report message. If the device under control correctly changes its state in response to a command from the first device, no status update is given. This reduces the amount of status reporting, thereby reducing data traffic.

[0079] The device under control processor 22 may further be configured to send a status report message if a control command is sent from the first device and not complied with. However, if the control command is not complied with by a margin below the threshold, the sending of the status report message is suppressed while still maintaining an accurate overview of the state of the device under control.

[0080] In this case, if the command is sent from the first device, there are the following options. - The control command was complied with: The status report message is suppressed. - The control command was nearly complied with, i.e., the state was changed within the threshold margin of the control command: The status report message is suppressed. - The control command was not even generally complied with, i.e., the state was not changed or the state was changed beyond the threshold margin of the control command: The status report message is sent.

[0081] If the command is not sent from the first device, a status report message is sent.

[0082] If the control command is not sent from the first device, a status report message is sent.

[0083] In this way, even if the command is sent from the first device, if the command cannot be complied with, a status report message is sent. For example, the controlled device may not have the capability to comply with the control command (partially or entirely). In this way, the status report is sent to ensure that the first device (or the status monitoring device) is aware that the command has not been (partially or entirely) followed. For example, the command may be for setting an unsupported color temperature (e.g., 5000K). In this case, the closest available color temperature (e.g., 4000K) is set and the set value is reported. If the command is not complied with but is a minor discrepancy (e.g., rounding error or quantization error, etc.), the status report may be suppressed.

[0084] The controlled device can determine whether a control command (e.g., for changing light) is sent from the first device by comparing the network address of the source of the control command with the network address of the destination of the attribute report message when the first device is also the source.

[0085] As described above, in some network configurations, this may not apply because the report collector is a different device from the source of the command. One or more sources of the command may be associated with the status monitoring device so that the status monitoring device can receive updates in-band or out-of-band (i.e., recognize the control commands that have been sent or will be sent). This option may be implemented by having one or more additional parameters in the attribute reporting configuration. Alternatively, the controlled device may be instructed (e.g., by some manufacturer-specific command) not to send an attribute report when receiving control commands from one or more addresses. All control commands may be "known" to the monitoring function, and there may be multiple controllers, in which case multiple addresses may be used.

[0086] Thus, one of the basic options is that the command does not report when it comes from a network device that is also the destination of the reporting message. Another option is that the command does not report when it comes from a network device that matches a specific network address.

[0087] The first device 12 includes a first device controller transceiver 26 (which has a first device transmitter for sending control commands and a first device receiver for receiving status report messages), and a memory 28 for storing network state data. The first device processor 30 is used to control the transmitter. The first device processor maintains a network state message based on the control command and the received status report message.

[0088] In an example where the first device is also a status monitoring device, the first device assumes that its commands are being obeyed and updates the network state data (e.g., a table) until a status report message indicates otherwise. Thus, the status report message overrides the assumed value. This can speed up the update of the status report data, which would otherwise require polling with associated delays.

[0089] The network state data can be any data structure or database for storing the network state, and can take the form of a single table, multiple tables, a list, a linked list, etc.

[0090] Even if the first device (the command originator) and the status monitoring device (the reporting collector) are the same device, there can be situations where attribute reporting is still useful. For example, the first device may send a command to set a lighting fixture to a color temperature of 2000K. However, the device only supports 2200 - 5000K due to the capabilities of the LEDs provided in the device. In this case, this will be processed to the nearest possible value (2200K), and in this case, it is necessary and useful to report the actual value (2200K). Because otherwise, the status monitoring device will think that the lighting fixture has actually moved to 2000K.

[0091] For the determination of whether to send this "deviation" from the indicated value, existing Zigbee (registered trademark) threshold parameters may be used to indicate how much the value should change before being reported. In this case, the deviation indicates how different the actual value is from the value that was last reported. Of course, alternatively, additional (dedicated) parameters may be added to the configuration of the attribute reporting. This prevents the reporting of very small changes, for example, when a lighting fixture is instructed to be at a color temperature of 3004K and due to internal quantization, it can only be at values such as 2992K, 3001K, 3010K, etc. In this case, 3001K, which is the nearest possible value, will be used, but it hardly makes sense to send a report of this slight deviation. In this case, since the difference of 3K is below the threshold, the report is not sent.

[0092] In the case of a command sent by the first device where the device cannot fully comply with the command (for example, refer to the 2000 / 2200K example above), the database may first be updated by the status monitoring device (to 2000K) when the command is sent. After the lighting fixture adopts the nearest possible value (2200K) and reports the new value, the database is updated to the actual value of 2200K.

[0093] When the lighting fixture is controlled by an external means such as a main power switch, Bluetooth (registered trademark), or another Zigbee (registered trademark) controller, since the source of the change is not linked to the control device or known to the status monitoring device, the lighting fixture reports to the status monitoring device to keep the database up-to-date.

[0094] When the main power is turned off, the device to be controlled may send a so-called last breath message when it detects that the power has started to drop, informing the status monitoring device that the device (a) turns off and (b) is no longer reachable.

[0095] When the lighting fixture is controlled via streaming, attribute reporting will not be sent. The status monitoring device (or the first device) may report the current settings of the device to the participating app, or may indicate a value of "varying" instead of the brightness or color value.

[0096] Some commands may involve a slow transition. For example, a "wake-up" function may be implemented where the first device sends a command to the lighting fixture "switch on with brightness = 1%" followed by a command "go to brightness = 75% with 30 minutes transition time".

[0097] In the case of normal attribute reporting, as a result, messages occur from the lighting fixture every X seconds, and the values in the database are updated only once every X seconds. However, since the lighting fixture continues to increase in brightness, the values in the database will lag behind the actual values.

[0098] This is improved by reflecting that a transition is in progress in the database (e.g., "moving from brightness = A at timestamp TA to brightness = B at timestamp TB") and enabling the actual state to always be computable when the device or app needs to know. In this way, the attribute reports from the luminaires also reflect that such a transition is in progress. In this case, the status report message may be in the form of "moving from brightness = A at timestamp TA to brightness = B at timestamp TB".

[0099] Of course, this status report message need not be sent if the command is originated from the status monitoring device or from some other control device that recognizes the command sent by the status monitoring device to the control device.

[0100] When an endpoint is reached, or when the transition is interrupted by another command, an attribute report message may be sent.

[0101] In the case of entertainment and streaming, if there is a desire to have some indication of the state of the light, the message sent every X minutes may indicate the average brightness or color over the past X minutes, or the minimum or maximum brightness or color (coordinate space x, y) over the past X minutes. This may be used by the app to have some indication of the effect that the luminaire is generating.

[0102] Additionally, the first device processor may periodically poll the controlled device for status checks. In this way, the controlled device may not only report immediately in response to a status change, but may also perform slower reporting based on periodic polling. Polling provides, for example, a safety net against missing report messages. An override bit or flag may be used to enable the first device to force an immediate status check.

[0103] Figure 2 shows a network control method for one of the controlled devices. The first device transmits a control command to the controlled device.

[0104] In step 30, one such control command is received.

[0105] In step 32, the controlled device determines whether it can comply with the command. If it can, in step 34, the controlled device changes its state in response to the control command.

[0106] In step 36, the controlled device determines whether the control command was sent from the first device.

[0107] If the control command was sent from the first device and was complied with, in step 38, transmission of the status report message is suppressed, i.e., there is no message sent to the status monitoring device (which may be the first device or another monitoring device as described above).

[0108] If the control command was not sent from the first device, in step 40, a status report message is sent to the status monitoring device.

[0109] If the controlled device can partially comply (such as in the example of the light color temperature described above), in step 42, the deviation from the command is evaluated. If it exceeds the threshold, a status report message is sent again in step 40.

[0110] If the difference is less than the threshold, the method proceeds to step 36. Thus, again, there is a check whether the control command comes from the first device. If not, a status report message is sent in step 40, and if so, the sending of the status report message is suppressed in step 38.

[0111] Note that although the implementation of the transition function is not shown, the method may be extended as described above.

[0112] The network control method shown in FIG. 2 shows three options for step 32, namely, "complied with", "not complied with", "partially complied with", but "partially complied with" is not necessarily required. A simple example where "partially complied with" has no meaning is when the state change is a binary state change, where "partially complied with" has no meaning. However, even considering embodiments where the state change is not binary, such as in a system where the dimming of light is possible, strict compliance may be required, and in this case, it may be a design decision to use only "complied with" and "not complied with". However, such a decision comes at the cost of an increase in status reports, thus potentially leading to a higher network load.

[0113] FIG. 3 shows a network control method for a status monitoring device.

[0114] In step 50, the network state data is initialized.

[0115] In step 52, when the control command sent to the controlled device is received, in step 54, the network state data is maintained based on the control command.

[0116] In step 56, when a network state report message (e.g., prompted by a control command) is received, in step 58, the network state data is updated based on the received network state report message.

[0117] These two branches operate in parallel. For example, a command may be received first, and then a state report may be received that overrides the update in step 54. Alternatively, the state report may be received without receiving a control command.

[0118] The state monitoring device stores the network state data. In particular, the state monitoring device stores both the state based on the sent control command and the state from the incoming reports. The state is updated in response to known control commands and then further updated if a state report message is received.

[0119] The present invention is particularly interested in outdoor lighting networks (e.g., streetlights where a centralized controller maintains a mirror of the state of all streetlights), or alternatively, indoor lighting networks in building control systems or consumer systems.

[0120] The first device may indicate in the command whether attribute reporting is required. For example, the method of the present invention may be set as an optional operating mode among a plurality of possible operating modes.

[0121] The above example is based on a central controller and a set of devices that report to the central controller or a dedicated monitoring device. Other configurations are possible. For example, there may be multiple parties interested in the state. The central controller and / or the state monitoring device can set up attribute reporting for the controlled device, which may result in multiple entries for which reporting needs to be sent.

[0122] A network device (e.g., a mobile phone) may have reporting enabled, while the central controller may not have reporting enabled.

[0123] As described above, the attribute reporting defined by Zigbee (registered trademark) can be configured to send a report when there is a significant change from the last reported value and, (if there is no such significant change) still send a report message every N minutes. This N-minute report is relevant in case a report message is missed and ultimately ensures that the "state cache" of the receiving device of interest is correct. This N-minute report can also be used to determine whether the device is still reachable (the device may be powered off or suffering from a poor connection). The timeout N may be made to depend on the observed behavior. For example, if the device is found to be reliable (meaning that reports come every N minutes and the reported values match the "cache"), the timeout N can be increased. This reduces the traffic volume. If the device is found to be unreliable (meaning that reports do not come every N minutes or the reported values deviate from the "cache", suggesting another control source), the timeout N for that device can be decreased.

[0124] If the device is unreachable for a period of time, indicating that the main power supply has been turned off by the user for a certain period, the timeout N may be reduced so that power-down is detected earlier ("unreachable" detection is typically the case where no messages have been received for M*N minutes (M is a coefficient indicating the number of message drops required before the device is considered unreachable)).

[0125] In a situation where some devices in the system support the above method and some do not, the first device (central controller) may apply a combination of measures. For example, the above attribute reporting may be used for devices that support this, and normal attribute reporting may be used for other devices. Alternatively, the above attribute reporting may be used for devices that support this, and polling may be used for other devices.

[0126] There may also be situations where attribute reporting is combined with polling. The first device (which collaborates with the status monitoring device in the case of separate ones) may typically rely on attribute reporting. However, in certain situations, for example, when the device becomes periodically unreachable (meaning that the attribute report message has been lost), the device may additionally be polled, or if polling indicates a different value from the "cache", the polling rate may be increased. After a while, when polling again indicates a consistent value, the polling rate can be decreased.

[0127] Polling involves querying the device for the current values of attributes such as the on / off state and brightness level. The device is typically obliged to respond to these requests.

[0128] A further extension is to allow the controlled device to become disobedient in the presence of a controlled device and not respond in the absence of a change. Currently, in this case, the central controller will consider the controlled device to be unreachable. However, if both the central controller and the controlled device adapt to such an approach, the amount of messages can be reduced.

[0129] For example, the first device may periodically send many polling messages to each device, grouped into a single command if possible, so that there is no response (when the system is in a stable state).

[0130] By considering the drawings, the present disclosure, and the appended claims, variations to the disclosed embodiments can be understood by those skilled in the art and can be practiced when implementing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may perform the functions of several items recited in the claims. The mere fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used advantageously. When a computer program is described above, the computer program may be stored / distributed in a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms via the Internet or other wired or wireless telecommunication systems. It should be noted that when the term "adapted to" is used in the claims or the specification, the term "adapted to" is intended to be equivalent to the term "configured to". No reference signs in the claims should be construed as limiting the scope.

Claims

1. A networked system comprising a first device that executes a control function, a state monitoring device, and a plurality of controlled devices, wherein the first device is configured to send a control command to the controlled device, and the controlled device is configured to send a status report message to the state monitoring device, each controlled device includes a controlled device receiver for receiving a control command, a controlled device transmitter, and a controlled device processor, and the controlled device processor receives a control command for changing the device state from the first device or from another source of the command, changes the device state in response to the control command if the controlled device can comply with the control command, determines whether the control command was issued from the first device, suppresses the transmission of a status report message to the state monitoring device if the control command was issued from the first device and was complied with, and transmits a status report message to the state monitoring device if the control command was not issued from the first device. A system configured as such.

2. The controlled device processor, if the control command was issued from the first device and was not complied with, transmits a status report message, or suppresses the transmission of a status report message only if the control command was not complied with but was not complied with by a margin below a threshold, and transmits a status report message otherwise. The system according to claim 1, configured as such.

3. The first device includes a first device transmitter for sending a control command and a first device processor for controlling the first device transmitter, and the state monitoring device includes a monitoring device receiver for receiving a status report message, a memory for storing network status data, and a monitoring device processor configured to maintain the network status data based on the control command and the received status report message. The system according to claim 1 or 2.

4. ​ The monitoring device processor is configured to populate the network state data with static values and a transition function indicating a temporal transition of the values, and the controlled device processor is configured to generate a state report message indicating static values and optionally also a transition function. The system according to claim 3.

5. The system according to claim 3, wherein the first device processor or the state monitoring device is configured to periodically poll the controlled device for a state check.

6. The system includes a networked lighting system, the controlled device includes lighting fixtures, and the control command is an on / off command, a brightness level command, a color temperature command, a color setting command, and includes one or more of the above. The system according to any one of claims 1 to 5.

7. A controlled device for being controlled by a first device of the network that is used in the network and executes a control function, the controlled device including a controlled device receiver for receiving a control command from the first device, a controlled device transmitter, and a controlled device processor, and the controlled device processor receives a control command for changing the device state from the first device or from another source of the control command, when the controlled device can comply with the control command, changes the device state in response to the control command, determines whether the control command was transmitted from the first device, when the control command was transmitted from the first device and was complied with, suppresses transmission of a state report message to the state monitoring device, and when the control command was not transmitted from the first device, transmits a state report message to the state monitoring device. The controlled device is configured as such.

8. When the control command was transmitted from the first device and was not complied with, the controlled device processor transmits a state report message, or suppresses transmission of a state report message only when the control command transmitted from the first device was not complied with but was not complied with by a margin below a threshold, and transmits a state report message otherwise. The controlled device according to claim 7, configured as such.

9. The controlled device according to claim 7 or 8, wherein the controlled device is a lighting fixture.

10. A networked system, A first device that executes a state monitoring and control function in the networked system, A plurality of controlled devices, A networked system including: The first device is configured to transmit a control command to the controlled device, and the controlled device is configured to transmit a status report message to the first device. Each controlled device includes a controlled device receiver for receiving a control command, a controlled device transmitter, and a controlled device processor, and the controlled device processor Receives a control command for changing the device state from the first device or from another source of the command. When the controlled device can comply with the control command, changes the device state in response to the control command. Determines whether the control command was transmitted from the first device. When the control command is transmitted from the first device and is complied with, suppresses the transmission of a status report message to the first device, and When the control command is not transmitted from the first device, transmits a status report message to the first device. A system configured as such.

11. The first device A first device transmitter for transmitting a control command to the controlled device of the network, A status monitoring device for monitoring a state change of the controlled device of the networked system, Including, the status monitoring device A monitoring device receiver for receiving a status report message, A monitoring device processor, A memory for storing network status data, Including, The monitoring device receiver is from a controlled device, The controlled device changed its state in response to a control command not transmitted by the first device, or The controlled device did not comply with a control command transmitted by the first device, Is configured to receive a status report message indicating this, The monitoring device processor When a control command is sent by the first device to a device under control, assuming compliance by the device under control, adapting the network state data of the device under control based on the control command sent to the device under control When a status report message indicates that a control command sent by the first device to a device under control could not be complied with by the device under control, adapting the network state data of the device under control according to the received status report message, and When a status report message indicates that a device under control has changed its state in response to a control command not sent by the first device, adapting the network state data of the device under control according to the received status report message The system according to claim 10, configured to maintain network state data in this way

12. The system according to claim 11, wherein the first device is an illumination system controller

13. A status report message when a command is partially complied with indicates the current state of the device under control, and the monitoring device processor adapts the network state data of the device under control accordingly. The system according to claim 11

14. A network control method for a device under control for use in a networked system including a first device that executes a control function, a status monitoring device, and a plurality of devices under control, wherein the first device is configured to send a control command to the device under control, and the device under control is configured to send a status report message to the status monitoring device. The method includes, in the device under control Receiving a control command for changing the device state When the device under control can comply with the control command, changing the device state in response to the control command Determining whether the control command was sent from the first device When the control command was sent from the first device and was complied with, suppressing the transmission of a status report message to the status monitoring device When the control command has not been transmitted from the first device, transmitting a status report message to the status monitoring device; A method including the above. **Claim 15** A computer program including computer program code means, wherein the computer program code means is configured to implement the method according to claim 14 when the computer program is executed by a computer.

Images