JP2009260778A - Sensor network gateway, and sensor network system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sensor network system using a gateway which can detect the abnormality of a sensor node in a sensor net system by the gateway and can collect and duplicate data of the sensor node from a host computer by a polling method. <P>SOLUTION: The gateway comprises a table unit for periodically updating measurement data of sensor nodes and a data holding unit for storing data and is configured to monitor the updating cycle of the measurement data of the table unit and to determine abnormality of a sensor node if the cycle is delayed. A host computer comprises an ID setting unit for setting connection information of nodes, a gateway diagnosis unit and a switching unit, and a plurality of gateways can be selected and connected. Furthermore, when duplexed, data of the table are exchanged with each other between gateways and can be backed up mutually. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sensor network gateway that receives data from a sensor node that performs intermittent operation, and a sensor network system.

  Conventionally, information such as temperature and humidity measured by a terminal called a sensor node is intermittently operated and sampled every measurement cycle of several tens of seconds to several minutes, and is a host computer in real time using wireless communication means A network system (hereinafter referred to as a sensor network system) to be taken into a processing apparatus has been studied.

  A sensor network system is a small battery-operated sensor node that collects measurement data and wirelessly communicates with a sensor node and a device that collects sensed data wirelessly and connects to a wired network such as the Internet (hereinafter referred to as a gateway). And 3 types of devices (called nodes) called repeaters that perform wireless relay transmission when there is a distance between the sensor node and the gateway.

  Conventionally, in a sensor network system, the hardware configuration of a sensor node and a gateway is shared, and a memory for sequentially storing commands to the sensor node as a table is provided in the base station (gateway) to reduce the power consumption of the sensor node. There exists invention shown in Unexamined-Japanese-Patent No. 2006-211439 (patent document 1).

  In addition, a series of commands from a host computer is written in a simple language and scripted, and the system operation flow is dynamically constructed by analyzing and executing the script at each node gateway, router, and sensor node. Service information (signals) in a system in which ZigBee (registered trademark) is used as an invention or wireless communication standard disclosed in Japanese Unexamined Patent Application Publication No. 2006-344017 (Patent Document 2) and a plurality of sensor networks are integrated by an information management server The invention shown in Japanese Patent Application Laid-Open No. 2007-272399 (Patent Document 3) related to the transfer of the above-mentioned is presented.

  Furthermore, Japanese Patent Laying-Open No. 2005-328230 (Patent Document 4) also shows the contents of the gateway provided with the gateway.

  However, the above prior art has the following problems.

  The host computer needs to process the measurement data of a plurality of sensor nodes transmitted every measurement cycle via the gateway as events asynchronously, and real-time processing performance is required. For this reason, there is a drawback that there is a limitation of applicable hardware and event processing software that enables a plurality of asynchronous processes at the same time quickly.

  When the host computer becomes abnormal, there is no means to hold the measurement data from the sensor node in the gateway, and it is necessary to read the measurement data from the sensor node again when the host computer recovers. There is a disadvantage in that current is consumed and the operation time of the sensor node that performs battery operation is reduced.

  When a sensor node becomes abnormal, measurement data is not transmitted to the gateway or repeater in the wireless communication, but there is no means to determine the sensor node abnormality in the gateway, so the host computer detects the sensor node abnormality There is a drawback that the processing on the host computer side becomes complicated.

  Even in a plurality of sensor network systems, there is only one gateway, which is not considered when the gateway is stopped due to a gateway failure, etc., and measurement data from the sensor node is not transmitted to the host computer. There was a drawback that would stop the sensor network system.

JP 2006-211439 A JP 2006-344017 A JP 2007-272399 A JP-A-2005-328230

  The problem to be solved by the present invention is that the gateway of the above-described prior art sensor network system collects the measurement data from the sensor node, but does not hold the data and judges the abnormality, and sends the measurement data as an event to the host computer. The point of transmission is that the system is stopped when the gateway stops because it is composed of a single gateway.

An object of the present invention is to provide a sensor network system in which a host computer is simplified and highly reliable by holding measurement data of a sensor node and periodically updating the gateway at a gateway.
It is to provide a highly reliable sensor network system capable of simplifying the host computer and configuring a plurality of gateways.

  The present invention relates to a sensor network gateway having a plurality of sensor nodes and a gateway that receives measurement data measured by the plurality of sensor nodes directly or via a relay, wherein the gateway includes the measurement time information. It has a table part which updates and saves data periodically.

  According to the present invention, the sensor network gateway and the sensor network system can process measurement data from the sensor node by the gateway.

  For this reason, the host computer can process by issuing commands such as data collection to the gateway and receiving the response without being aware of the transmission procedure between the gateway, repeater, and sensor node of the sensor network system. The burden on the computer is reduced, and it is possible to collect data and determine node abnormalities with a simple host computer.

  The present invention is provided with a table unit for storing measurement data measured by sensor nodes while periodically updating the gateway, a period determination unit for determining whether measurement data is periodically updated, This is realized by providing an ID setting unit, a diagnosis unit, and a switching unit in the upper computer.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, a plurality of sensor nodes 2a, 2b, 2c, and 2d are operated by a battery, and a measurement operation is driven by a power source by the battery every preset measurement cycle. The measurement operation should be as short as possible to reduce battery power consumption. Usually, the battery life is about 1 year.

  The sensor node has a built-in temperature and humidity sensor, measures temperature and humidity at each measurement cycle, and measures data (temperature, humidity) and status (remaining battery level, radio wave intensity (RSSI), communication quality (LQI), self-diagnosis) Information) is gathered to form sensor node data, which is transmitted as a single data packet using radio (ZigBee).

  The repeaters 3a and 3b are installed between the gateway and the sensor node, and relay and transmit data packets transmitted from the sensor nodes 2a, 2b, 2c, and 2d to the gateway 1 at every measurement cycle.

  A repeater is usually installed when there is a distance between the sensor node and the gateway 1 and the radio wave is weak and the sensor node and the gateway cannot communicate directly. The gateway 1 receives data packets wirelessly transmitted from the repeaters 3a, 3b or the sensor nodes 2a, 2b, 2c, 2d by the ZigBee IF7.

  The gateway 1 stores the data packet captured by the ZigBee • IF 7 in the table unit 5. The table unit 5 is divided into IDs (MAC address or NWK address) for each node, extracts measurement data (temperature, humidity) and status data as sensor node data from the received data packet, and stores them in the corresponding ID. To do.

  The sensor node data stored in the table unit 5 is updated each time a data packet from the sensor node is received for each measurement cycle. For this reason, the sensor node data of the past data packet is lost as it is, and the means for periodically storing the data of the table unit 5 in the data holding unit 6 is provided so that the past data can be referred to.

  The host computer 4 composed of a PC, a server, or a controller and the gateway 1 are connected using a LAN such as ETHERNET (registered trademark). In order to collect sensor node data of each sensor node, a sensor network data processing unit 10 is provided in the host computer 4. The sensor network data processing unit 10 periodically polls the gateway 1 at the update cycle of the host computer 4 and issues a data collection command via the LAN / IF 9 independently of the measurement cycle of the sensor node.

  The gateway 1 receives a data collection command via the LAN / IF 8, retrieves each sensor node data (measurement data, status) previously stored in the table unit 5, and returns it as a response to the host computer via the LAN / IF 8. The host computer 4 temporarily stores the returned sensor node data in an internal file.

  The host computer 4 retrieves each sensor node data stored in the file as a GUI function, displays the trend of temperature and humidity, displays the alarm output and communication status when the temperature and humidity exceed the specified values, Inform the operator using the calculator.

  FIG. 2 shows the configuration of each node and the host computer.

  The sensor node 2a measures temperature and humidity by the sensor unit 15. Temperature sensors include thermistors, sensors that utilize the temperature dependence of the forward voltage drop of semiconductors, thermocouples, and resistance temperature detectors. Some humidity sensors capture changes in capacitance and impedance. In both cases, changes in temperature and humidity are converted into electrical signals and output.

  The sensor data input unit 16 receives electrical signals of temperature and humidity data, and those that output analog signals from the sensor unit perform AD conversion to convert them into digital signals of temperature and humidity. When AD conversion is performed by the sensor unit and a serial communication signal is output, a serial communication unit is provided in the sensor data input unit to convert the serial communication signal into a digital signal of temperature and humidity.

  The sensor data transmission IF unit 17 reads the measurement data (temperature, humidity) from the digital signals of temperature and humidity, and reads the current time from the RTC 19 to create a measurement time. Further, the sensor data transmission IF unit 17 obtains the status from the battery remaining signal output from the battery driving unit 19 and the radio wave intensity output from the ZigBee / IF 21, communication quality data, and self-diagnosis information such as disconnection and short circuit of the sensor unit. create.

  The sensor data transmission IF unit 17 collects the measurement time, measurement data (temperature, humidity) and status as sensor node data, and creates and outputs a data packet. The ZigBee IF 21 wirelessly outputs the data packet created by the sensor data transmission IF unit 17 using the destination address (AddressID) as a gateway or a repeater, and waits for reception of an ACK indicating that the data packet has been received.

  The ZigBee IF 21 ends the transmission of the data packet upon receipt of the ACK. If no ACK is received, a timeout occurs and the ZigBee IF 21 retransmits the data packet.

  In addition to the above, the sensor node enables battery operation for a long period of time, and in order to reduce battery consumption, the sensor unit 15, sensor data input unit 16, sensor data transmission IF unit 17, The ZigBee · IF 21 is stopped, the current consumption is reduced, and the operation is performed intermittently.

  The battery drive unit 19 receives electricity from the battery, supplies electricity to each part of the sensor node, compares the battery voltage with a reference voltage, for example, a 3V battery, and compares it with a reference voltage of 2.8 V. When the battery level is high, a battery level signal is output indicating that the remaining battery level is sufficient, and when the battery level is low, a low battery level signal is output.

  The drive control unit 18 subtracts the time output from the RTC 20 that performs the time measurement operation and the time of the previous operation, and when this exceeds a preset measurement cycle (hh: mm: ss), the sensor unit 15 and the sensor The data input unit 16, the sensor data transmission IF unit 17, and the ZigBee / IF 21 are activated, the ZigBee / IF 21 data packet is transmitted, and the reception is stopped when an ACK is received. The sensor nodes 2b, 2c, and 2d are configured similarly.

  The repeater 3a receives the data packet from the sensor node by the ZigBee IF 23, and wirelessly returns a reply ACK indicating that the data packet has been received to the sensor node. The ZigBee IF 23 outputs the data packet to the sensor data relay transmission unit 22. The sensor data relay transmission unit 22 creates a data packet using the destination address (AddressID) of the data packet as a gateway and outputs the data packet to the ZigBee / IF 23.

  The ZigBee IF 23 wirelessly outputs a data packet. The repeater 3a uses the radio field intensity, communication quality data and self-diagnosis information output from the ZigBee IF 23 of the repeater as a status, reads the current time from the RTC 24, creates a data packet of repeater data as a measurement time, It is transmitted by ZigBee · IF23. The repeater 3b is configured similarly.

  The gateway 1 receives the data packet from the repeater or the sensor node directly by the ZigBee IF7, and returns a reply ACK indicating that the data packet has been received to the repeater or the sensor node by radio. The ZigBee IF 7 outputs the received data packet.

  The table unit 5 receives the data packet, extracts the sensor node data, uses the source address (Source Address) included in the data packet as the node ID, and sends the measurement time, measurement data (temperature, Humidity) and status.

  The table unit 5 outputs table data for each table storage cycle having a fixed cycle. The data holding unit 6 stores the output table data in a buffer. The buffer holds n pieces of table data determined by the data holding capacity of the gateway, and when it exceeds this, the table data at the oldest time is discarded.

  The cycle determination unit 11 reads the measurement time stored in the table unit and the measurement cycle for each node ID, compares the time output from the RTC 12 that performs the time measurement operation, and RTC output time> “measurement time + n X measurement cycle”. (N is set to 2 or more).

  When “measurement time + n X measurement cycle” exceeds the RTC output time, it is determined that the sensor data of the sensor node is not updated, and an abnormality (ERROR) of the sensor node is detected. The abnormal status is output as abnormal.

  When the RTC output time has not exceeded, the normal / abnormal status is output as normal (NORMAL). Thereby, normality / abnormality of the sensor node is determined.

  The sensor data collection alarm check unit 26 of the sensor network data processing unit 10 of the host computer 4 issues a data collection command including a node ID to be collected via the LAN / IF 9 in order to collect each node data. The gateway 1 receives a data collection command via the LAN / IF 8.

  The LAN / IF 8 outputs a data collection command from the host computer to the command processing unit 14. The command processing unit 14 determines the command type of the host computer, reads the measurement time, measurement data (temperature, humidity) and status of the corresponding node ID from the table unit 5 and returns them to the host computer via the LANIF 8.

  The sensor data collection alarm check unit 26 receives the returned sensor node data via the LAN / IF 9 and stores it in the temperature / humidity recording file 27. The host computer 4 takes out each sensor node data stored in the temperature / humidity record file 27 and displays a trend of temperature and humidity. When the normal / abnormal status is abnormal, it displays an alarm of failure of the sensor node.

  The host computer 4 is provided with an ID setting unit 28 for registering node connection information in advance and collecting data. The ID setting unit 28 sets the type of each node configured as a system from the ID new, addition, deletion, and measurement cycle setting of the GW / router / sensor node provided with the GUI 30 (trend graph, alarm) and GUI 31 in the host computer. The node ID and sensor node measurement period are input and stored in the node registration ID file 29.

  The sensor data collection alarm check unit 26 reads the node ID for collecting data from the node registration ID file 29 via the ID setting unit 28. The ID setting unit 28 issues a node registration ID file 29 including a node registration ID file via the LAN / IF 9. The gateway 1 receives a node registration command via the LAN / IF 8.

  The LAN / IF 8 outputs a node registration command from the host computer to the command processing unit 14. The command processing unit 14 determines the command type of the host computer, and writes the node type, node ID, and measurement cycle in the table unit 5. This makes it possible to specify the ID of each node in the table unit 5 at the time of initialization after powering on the gateway. The measurement cycle written in the table unit 5 is output wirelessly via the ZigBee · IF 7.

  The sensor node receives the ZigBee • IF 21 via a repeater or directly from the gateway. The ZigBee IF 21 outputs the measurement cycle to the drive control unit 18. The drive control unit 18 stores the measurement cycle.

  As a result, the measurement cycle from the upper level of the sensor node can be set. The ID setting unit 28 issues a time registration command including the RTC time to the time output from the RTC 25 via the LAN / IF 9.

  The gateway 1 receives a time registration command via the LAN / IF 8. The LAN / IF 8 outputs a time registration command from the host computer to the command processing unit 14. The command processing unit 14 determines the command type of the host computer and sets the time in the RTC 12.

  Further, the gateway 1 outputs time data wirelessly via the ZigBee / IF 7. The repeater or the sensor node receives the data via the ZigBee • IF 23 or the ZigBee • IF 21 and sets the time data to the RTC 24 or the RTC 20. As a result, the sensor node is initially activated and can have a unified time in the system.

  FIG. 3 shows the relationship between the wireless data packet and the table unit 5.

A wireless data packet is composed of a control field and a data field. The control field includes preambles for synchronization and SD (Start) indicating the start of the packet.
of Frame Delimiter), Frame Length indicating the following packet length, Frame Control indicating the packet type, Sequence No indicating the packet number, Address ID indicating the destination address, and Frame Control to the data field from the end of the packet. It consists of FCS (frame check sequence) for bit error check.

  The data field includes a data length indicating the following length of the data field, a target address indicating the address of the last receiver, a source address indicating the address of the data packet source, a data type indicating the type of the data packet, and the source address Node type indicating sensor type, measurement time and measurement data as sensor data Temperature, measurement data Humidity, remaining battery level, radio wave intensity_communication quality, measurement cycle, data group of self-diagnosis information, check from node type to self-diagnosis information Therefore, Sum_check indicating data of the operation result of byte addition or exclusive OR is formed.

  The node ID, node type, and measurement cycle of the node registration ID file 29 are written in the table unit 5 from the ID setting unit of the host computer via the LAN / IF. In (1), the node ID of the table unit 5 that matches the source address of the data packet is retrieved upon reception of the wireless data packet. The node type and the measurement cycle of the item number of the node ID matched in (2) are confirmed. In (3), the data field measurement time to the self-diagnosis information are written in the item numbers matched in (2). Similarly, the process is executed every time a wireless data packet arrives.

  The cycle determination unit 11 reads the measurement time stored in the table unit for each node ID and the measurement cycle, compares the time output from the RTC 12 that performs the time measurement operation, and executes an update check of the measurement time. If not updated, the normal / abnormal status is set to abnormal (ERROR).

  FIG. 4 shows a transmission procedure (flow).

  The host computer executes the initial by starting (1). After completion of the initial in (2), a GW reset is issued via the LAN. The gateway (hereinafter referred to as GW in the figure) executes the initial by turning on the power of (1) or resetting the GW from the host computer. The repeater executes initial when the power is turned on in (1).

  The sensor node executes initialization when the power is turned on in (1). The GW clears the table portion at the initial of (1) and clears the normal / abnormal status (Null). The GW executes the destroy PAN in order to reset the PAN (Personal Area Network) held in the ZigBee • IF after the initial end in (2).

  The GW reconstructs the PAN held by the ZigBee • IF in the PAN construction of (3). In the PAN construction, a network join command is wirelessly issued from the GW to the repeater or the sensor node, and the repeater or sensor node receiving the reply returns a join response. A sensor node that cannot directly transmit wirelessly from the GW performs relay transmission using a repeater.

  The GW holds which ZigBee · IF is connected to which repeater and sensor node from the join response of the repeater or sensor node, and constructs a PAN. The GW sets the normal / abnormal status of the GW itself and the repeater or sensor node that has made the join response to INIT.

  Thereby, the difference between the contents of the node registration ID file of the host computer and the repeater or sensor node connected by the PAN response is confirmed. It is also possible to determine that the sensor node can be connected wirelessly but has not yet started measurement. The host computer confirms the GW status in (3) via the LAN.

  The GW reads the normal / abnormal status of the GW from the table section and returns INIT. The host computer executes the following (4), (5), and (6) when the GW status is INIT. In (4), the node registration file is read from the ID setting unit and set in the GW. The GW sets the data of the node registration file in the table part. The host computer reads the time from the RTC in (5) and sets it to the GW, repeater, and sensor node.

  The GW sets the time to the RTC and sets the time to the repeater and the sensor node. The repeater sets the time to the RTC and relays the time to the sensor node by relay transmission. The sensor node sets the time to the RTC. The GW sets the normal / abnormal status of the GW itself and the repeater to NORMAL (normal).

  The host computer sets the measurement cycle of the node registration ID file read in (4) in (6) to each sensor node. The GW sets the measurement cycle to the sensor node in (5). The sensor node that passes through the repeater performs relay transmission with the repeater and transmits it to the sensor node. The sensor node sets a measurement cycle in the drive control unit in (4).

  The sensor node starts collecting sensor data in response to the RTC time setting and measurement cycle setting. The start from the initial to the GW, the repeater, and the sensor node from the host computer is thus completed.

  The sensor node takes in the sensor data at (6) every measurement cycle. In (7), the sensor data is transmitted to the gateway. If there is a repeater, repeat the relay transmission with the repeater and transmit to the gateway. The GW updates the table data of the corresponding ID from the sensor data in (6).

  In addition, the normal / abnormal status of the sensor node with the updated ID is set to NORMAL (normal). The GW makes a period determination in (7). The cycle determination unit compares the measurement time of the sensor node with the RTC, and sets the normal / abnormal status of the sensor node to ERROR (abnormal) when RTC output time> (measurement time + n × measurement cycle).

  The GW stores the table data in the data holding unit at every table storage cycle predetermined in (8). The GW periodically executes the search for additional joining nodes in (9). A network join command is issued, and the repeater or sensor node checks whether there is a new addition. When a sensor node is added, the additional sensor node returns a join response. When a repeater is added, the repeater returns a join response.

  When a sensor node is added, the GW reads the RTC time in the GW and the measurement cycle of the table, continues to execute (4) and (5), and starts sensor data collection for the sensor node. When the repeater is added, the RTC time in the GW is read, and then (4) is performed, and the normal / abnormal status of the repeater is set to NORMAL (normal).

  Thereby, it is possible to add a node in the GW. The GW periodically executes (6) to (9).

  The host computer reads the sensor data stored in the GW table according to the following procedure and performs processing. (7) Check the GW status. The GW returns the normal / abnormal status of the GW in the table.

  The host computer executes (8) when the status is NORMAL, and executes (4), (5), and (6) when it is INIT. The sensor data of the GW table is read in (8). The GW returns the sensor data of the specified ID table. In (9), it is checked whether the normal / abnormal status of the GW, repeater, or sensor node is ERROR (abnormal). If abnormal, an alarm is output. In (10), the sensor node sensor data is stored in a temperature and humidity recording file. In (11), a trend / graph is displayed from the temperature / humidity data.

  The host computer repeats (7) to (11). When the host computer refers to past table data, the table data stored in the data holding unit is read from the GW in (12). The GW reads the table data from the data holding unit and returns it. The read data is saved in a temperature / humidity record file.

  FIG. 5 shows a configuration in which two gateways, a master and a slave, are used.

  The gateway (master) 1a and the gateway (slave) 1b are configured similarly to the gateway 1 shown in FIG. The gateway includes a ZigBee · IF 7a (master), a ZigBee · IF 7b (slave), a cycle determination unit 11a (master), a cycle determination unit 11b (slave), an RTC 12a (master), and an RTC 12b (slave).

  The gateway (master) 1a and the gateway (slave) 1b are set by changing the node IDs of the GW (master) and GW (slave) in the table units 5a and 5b in order to identify the addresses of the radio units. Similarly, in order to distinguish the LAN from GW (master) and GW (slave), the LAN IF 8a of the (master) 1a and the IP address of the LAN IF 8b of the gateway (slave) 1b are set differently.

  When a wireless transmission abnormality occurs, in FIG. 5, for example, when a failure including retransmission occurs during transmission from the sensor node 2a to the repeater 3a, the sensor node 2a switches the address to another repeater 3b. If this is successful, the sensor node 2a switches the destination from the repeater 3a to the repeater 3b.

  Similarly, if the repeater 3a also fails during transmission to the gateway (master) 1a, including the retransmission, the repeater 3a switches the address to another gateway (slave) 1b. If this is successful, the repeater 3a switches the destination from the gateway (master) 1 to the gateway (slave) 1b.

  As a result, even if one repeater and gateway fail, the sensor data of the sensor node can be transmitted by switching to another repeater and gateway.

  Since the host computer corresponds to a plurality of gateways, a switching unit 34, a diagnosis unit 32, and a connection ID file 33 are provided between the LAN / IF 9 and the sensor data collection alarm check unit 26 and the ID setting unit 28 in the sensor network data processing unit. Provide.

  The diagnosis unit 32 receives the node registration ID file transmitted from the ID setting unit 28 to the gateway, transmits the node registration ID file to the gateway via the LAN / IF 9, writes the node type and node ID of the connection ID file 33, the gateway, the sensor node, Register repeater connection information. The diagnosis unit 32 periodically transmits a diagnosis command to the gateway (master) 1 a and the gateway (slave) 1 b via the LAN / IF 9.

  The gateway (master) 1a and the gateway (slave) 1b receive a data collection command via the LAN / IF 8a or the LAN / IF 8b. The LAN / IF 8a or the LAN IF 8b outputs a diagnostic command from the host computer to the command processing unit 14a or the command processing unit 14b.

  The command processing unit 14a or the command processing unit 14b determines the type of command of the host computer, and reads the normal / abnormal status of all nodes as diagnostic data from the table unit 5a or the table unit 5b at a time. -Reply to the host computer via IF8b.

  The diagnosis unit 32 of the host computer receives diagnosis data via the LAN / IF 9. The normal (NORMAL) diagnostic data of the gateway (master) 1a writes the GW (master) to the connection ID of the connection ID file. In the normal (NORMAL) diagnostic data of the gateway (slave) 1b, GW (slave) is written in the connection ID of the connection ID file.

  If neither the gateway (master) 1a nor the gateway (slave) 1b is normal (NORMAL), the gateway (master) is prioritized and the GW (master) is written.

  FIG. 5 shows the connection ID file structure.

  (1) Indicates that the gateway (master) is operating only, (2) Gateway (slave) indicates that the gateway (master) is operating on the gateway (slave) when the gateway (master) stops due to failure, etc. (3) The gateway (master / slave) has a wireless status that changes between the nodes, indicating that both gateways (master / slave) are operating.

  Thus, the connection ID indicates whether each node is connected to the gateway (master) 1a or the gateway (slave) 1b, and the sensor data in the table is read from the connected gateway.

  The sensor data collection alarm check unit 26 of the host computer issues a data collection command including the node ID to be collected in order to collect each node data. The switching unit 34 reads the connection ID file 33 via the diagnosis unit 32, and switches the issue destination of the data collection command from the connection ID of the connection ID file 33 to the gateway (master) 1a or the gateway (slave) 1b. As a result, the gateway can be switched to operate when it fails or stops.

  FIG. 6 shows a configuration in which the gateway sensor data can be exchanged between the gateways when the gateways are duplicated.

  The host computer 4 is configured in the same manner as in FIG. In order to exchange the sensor data of the table, a data exchange unit 35a and a data exchange unit 35b are provided in the gateway (master) 1a and the gateway (slave) 1b.

  As shown in the configuration of FIG. 2, the gateway (master) 1a or the gateway (slave) 1b stores the data in the table unit 5a or the table unit 5b in the data holding unit 6a or the data holding unit 6b at every fixed table storage cycle. To do.

  At this time, the data exchange unit 35a or the data exchange unit 35b reads the table data stored in the table unit 5a or the table unit 5b via the data holding unit 6a or the data holding unit 6b, and the gateway (master) 1a is the gateway (slave). 1b, the gateway (slave) 1b transmits to the gateway (master) 1a via the LAN / IF 8a or the LAN / IF 8b.

  The data exchange unit 35a or the data exchange unit 35b on the receiving side discriminates the normal / abnormal status of each node of the transmitted table data, and sends the sensor data of the normal (NORAML) node to the data storage unit 6a or the data storage unit 6b. Write to the latest saved table data.

  As a result, even if either the gateway (master) 1a or the gateway (slave) 1b is stopped due to a failure or the like, the table data before the stop is stored in the data holding unit, so that the remaining gateways are intermittent. Data backup is possible.

  FIG. 7 shows a configuration in which the sensor data of the table can be exchanged between the gateways when the LAN line is duplicated with the a line and the b line when the gateway is duplicated.

  The gateway (master) 1a and the gateway (slave) 1b are configured in the same manner as in FIG. In order to make it possible to exchange the sensor data of the table via the host computer, the host computer 4 is provided with the LAN / IF 9a and the LAN / IF 9b on each of the a line and b line, and the table data relay unit 36 is provided.

  The gateway (master) 1a or the gateway (slave) 1b is a data exchange unit 35a or a data exchange unit 35b, and transmits table data to the other party via the LAN / IF 8a or the LAN IF 8b. Since it is not directly connected, the table data relay unit 36 of the host computer 4 receives the table data sent from the data exchange unit 35a or the data exchange unit 35b via the LAN / IF 9a or the LAN / IF 9b.

  The table data relay unit 36 transmits the table data received on the a line to the b line and the table data received on the b line to the a line via the LAN / IF 9a or the LAN / IF 9b, respectively.

  The data exchange unit 35a or the data exchange unit 35b of the gateway (master) 1a or the gateway (slave) 1b writes the received table data to the data holding unit 6a or the data holding unit 6b in the same manner as the configuration shown in FIG. As a result, even if the line is duplicated, backup is possible without any interruption. If there are 3 gateways, use 3 lines. As the number of gateways increases, it is desirable to increase three lines.

The main features of the embodiment described above are listed.
(1). The gateway includes a table unit that periodically updates and saves measurement data including measurement time information.

Since the gateway periodically updates and saves measurement data, the host computer is free from the burden of sensor data measurement data update management, so that the host computer can be a simple computer.
(2). The gateway includes a data holding unit that holds measurement data before being updated. The gateway can provide past measurement data according to the request of the host computer.
(3). The gateway includes a table unit that periodically updates and saves measurement data including measurement time information, and a cycle determination unit that determines whether the measurement data is properly updated.

Since the measurement data is updated under proper management by the cycle determination unit, it is possible to provide appropriate measurement data to the host computer side.
(4). The period determination unit is provided with time information of measurement data stored in the table unit and an RTC that performs a timekeeping operation, so that the RTC can perform update management of time accuracy.

Since the update management of measurement data is performed according to the RTC time, the time accuracy of the update is improved.
(5). Each sensor node has a switching function for selecting and switching a plurality of connection destination relays or a plurality of connection destination gateways, and each relay node has a switching function for selecting and switching a plurality of connection destination gateways. Prepared.

By the above selection switching, troubles such as communication interruption can be quickly resolved.
(6). The host computer includes an ID setting unit that registers IDs that are connection information of gateways, sensor nodes, and repeaters, a sensor node that is connected to the gateway through a diagnostic frame, and a diagnosis unit that collects connection information of relays A switching unit that switches the gateway of the data collection destination by a switching signal from the diagnostic unit is provided, and the switching can be performed when the gateway or the repeater fails or is stopped.

A specific diagnosis at the time of failure or stop can be accurately performed to quickly resolve the failure or stop.
(7). The plurality of gateways are provided with a data exchanging unit for storing table information stored in the table unit even on the other side, so that backup can be performed without interruption even if the other side stops due to a failure or the like.

Since the measurement data is backed up by the data exchange unit, when a failure occurs, the backup stored in the other gateway can be quickly resolved.
(8) Each gateway is connected to a host computer via an individual line, the host computer is provided with a table part data exchange part, and a table part sent from the gateway to the table part data exchange part via the line The table data was sent to another gateway via another line.

  When one of the lines fails in communication, the communication can be concentrated on the remaining lines and the communication can be continuously maintained. In addition, backups can be stored and retrieved in another gateway through the line and table data exchange units.

  In a sensor network system that measures the temperature and humidity of the site with sensors using wireless, there is no wiring cost, which is a feature of wireless, there is no wiring cost, and it can be installed in a free place, it is simply a host computer It is possible to construct a highly reliable network by duplication and connection and change.

  Further, the sensor type is applicable not only to temperature and humidity but also to various sensors such as a 4/20 mA current signal and an acceleration sensor by corresponding the sensor unit of the sensor node.

It is explanatory drawing which showed the implementation method of a sensor network (Example 1). It is explanatory drawing which showed the implementation method of each node and a high-order computer (Example 2). 4 is an explanatory diagram showing a relationship between a wireless data packet and a table unit 5; FIG. It is explanatory drawing which showed the transmission procedure (flow figure). (Example 3) which was the time of duplicating a gateway with a master and a slave. (Example 4) which is the figure which showed exchange of table data between gateways, when a gateway is duplexed. FIG. 10 is an explanatory diagram showing exchange of table data between gateways when a LAN line is duplicated (Example 5).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Gateway, 1a ... Gateway (master), 1b ... Gateway (slave), 2a ... Sensor node, 2b ... Sensor node, 2c ... Sensor node, 2d ... Sensor node, 3a ... Repeater, 3b ... Repeater, 4 ... Host computer, 5 ... Table unit, 5a ... Table unit (master), 5b ... Table unit (slave), 6 ... Data holding unit, 6a ... Data holding unit (master), 6b ... Data holding unit (slave), 7 ... ZigBee / IF, 7a ... ZigBee / IF (master), 7b ... ZigBee / IF (slave), 8 ... LAN / IF, 8a ... LAN / IF / IF (master), 8b ... LAN / IF / IF (slave), 9 ... LAN / IF, 9a ... LAN / IF (a line), 9b ... LAN / IF / IF (b line), 10 ... sensor network data processing unit, 1 Cycle determining unit 11a Cycle determining unit (master) 11b Cycle determining unit (slave) 12 RTC 12a RTC (master) 12b RTC (slave) 14 Command processing unit 14a Processing unit (master), 14b ... Command processing unit (slave), 15 ... Sensor unit, 16 ... Sensor data input unit, 17 ... Sensor data transmission IF unit, 18 ... Drive control unit, 19 ... Battery drive unit, 20 ... RTC 21 ... ZigBee / IF, 22 ... Sensor data relay transmission unit, 23 ... ZigBee / IF, 24 ... RTC, 25 ... RTC, 26 ... Sensor data collection alarm check unit, 27 ... Temperature / humidity recording file, 28 ... ID setting unit 29 ... Node registration ID file, 30 ... GUI (trend graph, alarm), 31 ... GUI (GW / router / sensor node: D new, addition, deletion: measurement cycle setting), 32 ... diagnostic unit, 33 ... connection ID file, 34 ... switching unit, 35 ... data exchange unit, 35a ... data exchange unit (master), 35b ... data exchange unit (slave) ), 36... Table data relay unit.

Claims (8)

In a sensor network gateway having a plurality of sensor nodes and a gateway for receiving measurement data measured by the plurality of sensor nodes directly or via a relay,
The gateway for a sensor network, wherein the gateway includes a table unit that periodically updates and stores the measurement data including measurement time information. The gateway for sensor networks according to claim 1,
The gateway for a sensor network, wherein the gateway includes a data holding unit that holds the measurement data before being updated.   A plurality of sensor nodes, a gateway that receives measurement data from the plurality of sensor nodes directly or via a relay, and the measurement data that is provided in the gateway and includes measurement time information is periodically updated and stored. A sensor network gateway, comprising: a table unit; and a period determination unit that is provided in the gateway and determines whether the measurement data stored in the table unit is properly updated. In the sensor network gateway according to claim 3,
The gateway has an RTC for clocking operation,
The period determining unit determines whether the measurement data is properly updated based on time information of the measurement data stored in the table unit and time information of the RTC. . In a sensor network system having a host computer including a personal computer, a server, a controller, a plurality of gateways connected to the host computer, and a plurality of sensor nodes connected to each of the gateways directly or via a relay ,
Each of the sensor nodes has a switching function of selectively switching the relays of a plurality of connection destinations or the gateways of a plurality of connection destinations,
Each of the repeaters has a switching function for selecting and switching the gateways of a plurality of connection destinations. In a sensor network system having a host computer including a personal computer, a server, a controller, a plurality of gateways connected to the host computer, and a plurality of sensor nodes connected to each of the gateways directly or via a relay ,
The host computer includes an ID setting unit that registers an ID that is connection information of the gateway, the sensor node, and the repeater, and the sensor node that is connected to the gateway through a diagnostic frame and connection information of the repeater And a switching unit that switches the gateway of the data collection destination by a switching signal from the diagnostic unit,
A sensor network system, which can be switched and operated when the gateway or the repeater fails or stops. In a sensor network system having a host computer including a personal computer, a server, a controller, a plurality of gateways connected to the host computer, and a plurality of sensor nodes connected to each of the gateways directly or via a relay ,
The plurality of gateways include a data exchange unit for storing table information stored in the table unit on the other side as well,
A sensor network system that enables backup without interruption even if the other party stops due to a failure or the like. The sensor network system according to claim 7,
The individual gateways are connected to the host computer via individual lines,
The host computer is provided with a table data exchange unit,
The table data of the table unit sent from the gateway to the table unit data exchange unit via the line is transmitted to another gateway via another line.

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