NZ718049A - Environmental monitoring system - Google Patents

Abstract

The invention provides a system for monitoring of one or more environmental parameters measured at one or more sensors located at a plurality of sites, the system comprising one or more data collectors at each site communicating with a remote server, wherein: the data collectors at each site are adapted to collect and store values of the environmental parameters measured by associated ones of the sensors at measurement times, and to communicate the values to the remote server; and the remote server comprises a communications interface to interact and communicate with the data collectors and with users of the system, a database to store the values of the environmental parameters and a reporting subsystem to generate reports and alerts for designated ones of the users. dapted to collect and store values of the environmental parameters measured by associated ones of the sensors at measurement times, and to communicate the values to the remote server; and the remote server comprises a communications interface to interact and communicate with the data collectors and with users of the system, a database to store the values of the environmental parameters and a reporting subsystem to generate reports and alerts for designated ones of the users.

Description

ENVIRONMENTAL MONITORING SYSTEM FIELD The present invention relates to environmental monitoring such as the temperature of refrigerators, and an improved system for environmental monitoring and reporting BACKGROUND With the increased regulation and general consciousness regarding food safety, the monitoring of the conditions under which food is stored has become increasingly important. While temperature monitors exist that can monitor temperature conditions within a refrigerator and report alarm signals locally or over networks, there are many points of weakness in existing systems that prevent optimal and reliable monitoring, including: - a local electronics system is relied upon to remain switched on, correctly functioning, correctly set and operational; - there is no record transmitted to a data centre of actual temperature conditions, just the existence of an alarm state - because of lack of recording, there is no audit trail to verify the environmental conditions and their history over time, which is an important determiner of food safety.

There is therefore a need to provide an improved system which overcomes one or more of these disadvantages.

SUMMARY OF THE INVENTION In accordance with a broad aspect of the invention there is provided a system for monitoring of one or more environmental parameters measured at one or more sensors located at a plurality of sites, the system comprising one or more data collectors at each site communicating with a remote server, wherein: the data collectors at each site are adapted to collect and store values of the environmental parameters measured by associated ones of the sensors at measurement times, and to communicate the values to the remote server; and the remote server comprises a communications interface to interact and communicate with the data collectors and with users of the system, a database to store the values of the environmental parameters and a reporting subsystem to generate reports and alerts for designated ones of the users.

In one embodiment, the reporting subsystem generates alerts according to excursions of the measured values of the environmental parameters above or below one or more limits. The limits may be set by authorised ones of the users for each sensor at each site. The reporting subsystem may generate alerts only after the excursion has continued for more than an alert wait time. The alerts may be communicated to the designated ones of users by SMS, email or other mode of electronic communication according to a recorded preference.

In one embodiment, the environmental parameters include temperature of an enclosure.

In one embodiment, the data collectors are also adapted to collect and store values of a battery voltage of one or more of the associated sensors which are powered by battery. The reporting subsystem may generate alerts when the battery voltage of a sensor falls below a limit indicative of the need to replace or recharge the battery of the sensor.

In one embodiment, the data collectors are also adapted to collect and store the measurement times and communicate the measurement times to the remote server.

In one embodiment, the reporting subsystem generates alerts when a data collector fails to communicate values as scheduled from one of its associated sensors or when a data collector communicates to the reporting subsystem concerning a communications fault with one or more of the associated sensors.

In one embodiment, the reporting subsystem is adapted to generate a report for each site, the report comprising a history of stored values and measurement times received by the remote server.

In one embodiment, the communication between the data collectors to the remote server comprises redundancy in the case of communications failure, including multiple DNS server addresses.

In one embodiment, the communication between the data collectors to the remote server proceeds via a digital mobile telephone link from this data collector to an Internet provider.

In one embodiment, the database comprises redundancy in the case of failure or inaccessibility of a data storage medium, the redundancy comprising two replicated database machines in relative geographical proximity but isolated in terms of power supply, Internet connection and cooling.

In one embodiment, the system further comprises additional redundancy in the form of a backup server which can be used as a recovery point in the case of complete system failure.

In one embodiment, a power consumption is reduced in battery-powered wireless ones of the sensor units by the associated data collector periodically communicating a sleep time to said sensor units after receipt of data, and said sensor unit switching to a low-power sleep mode for the sleep time.

BRIEF DESCRIPTION OF DRAWINGS Figure 1 is a functional block diagram of an embodiment of the system; Figure 2 is a functional block diagram of detail of the data collectors and associated sensors of the embodiment of Figure 1.

DETAILED DESCRIPTION OF EMBODIMENTS An embodiment of the current invention will now be described.

Referring first to Figure 1, the system comprises a plurality of data collectors such as 20, 21 connected via a digital mobile telephone link through the internet to a remote server comprising a web server communications interface 100, database 200 and reporting subsystem 300. Web server 100 acts as a frontend to the database 200 for users, administrators and the data collector units 20, 21. There is no direct access to database 100 from the public internet. Web server 100 and report subsystem 300 are each interconnected and connected to an SMS messaging service 400 for communication of reports and alerts.

Data collectors 20, 21 may be located at a single geographical site or a number of geographical sites owned by a single entity or owned by separate entities. Each data collector is associated with one or more sensors 30, 31 which may be directly wired to data collector 20 or in communication over a local radio connection.

Web server 100 comprises redundancy in identical web servers 101 and 102 which are both at all times able to respond to traffic. Should one of them fail, there are multiple mechanisms which come into play to limit the effect. Firstly, multiple routing methods can be used to ensure the availability of at least one healthy machine. If a single server does fail, it will be detected as faulty, as it will not pass its automated tests (run daily, or more frequently) and the machine can be removed from the DNS records and an alert sent to a system administrator. The server can then be rebooted, re-instantiated or replaced to resolve the problem. Web server 100 may also comprise redundancy in the communication with the data collectors in the case of communications failure, including the provision of multiple DNS server addresses.

Similarly, database 200 comprises redundancy in replicated master 201 and slave 202 databases. An automatic failover event will occur if the master machine 201 becomes unreachable, substituting slave 202 database. At this point, a system administrator can fix the problem. The master 201 and slave 202 are located in relative geographical proximity, but are isolated in terms of power supply, internet connection and cooling. This reduces significantly the likelihood of both master 201 and slave 202 failing simultaneously. Considering the importance of the historical data communicated from the data collectors 20, 21, the database 200 is also backed up periodically, as often as practicable, over the internet to a third backup server 203 located at the premises of the system manager. Backup server 203 does not participate in automatic failover, but can be used as a recovery point in the case of a complete system failure. In such an event, the remote backup of the database can be used to seed a new deployment. Recovery from such a complete disaster is a manual procedure involving preparing the new database, and enabling the remaining servers.

In direct data communication with database 200 is a reporting subsystem 300 comprising redundancy in the form of master reporting system 301 and report failover reporting system 302. Reporting subsystem 300 is connected redundantly via to an SMS messaging system 400 utilising redundant SMS messaging services 401, 402. Reporting subsystem 300 is programmed to provide to designated users alerts, via SMS, email or other mode of electronic communication according to a recorded preference for each user. Alerts are generated typically when there is an excursion of a temperature measured at a temperature sensor outside the low and high set limits for greater than a pre- determined time known as the wait time. The alert wait time is set at a particular value which represents a desired balance between timely alerts of serious excursions and excessive false alarms. Alerts may also be generated when the measured battery voltage of a wireless battery power since. Low limit indicative of the need to replace or recharge a battery of the sensor.

Reporting subsystem 300 is also programmed to provide periodic reports as specified by clients, typically of the time profile of temperature recorded at each sensor for the site.

The reporting subsystem also generates alerts when a data collector fails to communicate values as scheduled from one of its associated sensors or when a data collector communicates to the reporting subsystem concerning a communications fault with one or more of the associated sensors.

A plurality of users 10, 11 are able to connect by Internet to communications interface web server 100 in order to perform administration, enter installation parameters, request reports, and change a range of preferences, depending on whether the user has administration, installer, or other privileges.

Typically, each site represents a separate corporate client, and users of each corporate client are entitled to access information concerning the data collectors at their site, together with varying privileges to amend various parameters such as contact details, low and high temperature limits and the like. The reporting subsystem reports of alerts and all reports to designated ones of those users as set up by configuration files stored on the system.

Other classes of users including installers who are authorised to configure sensors, data collectors and other such parameters through web server 100. Configuration parameters such as are described herein together with the historical temperature and battery voltage data are stored in a relational database appropriate designed as is known in the art.

Now referring to Figure 2, further details of the data collector 20 are discussed. The example shown is where one of the sensors is a wired sensor and another is a wireless battery powered sensor.

The wired sensor comprises a sensor node 30 inside a monitored enclosure 40 such as refrigerator, containing temperature sensor 34 directly wired through a wall of the enclosure 40 for power at 3.3 V and communication to data collector 20 via interface electronics 22.

The wireless sensor comprises a battery powered sensor node 31 in 2 parts containing temperature sensor 34 within monitored enclosure 41 connected by a short power and communications cable to radio and power module 33 housed outside the monitored enclosure. Radio and power module 33 houses a radio transmitter, 3 AAA batteries and 3.3 V regulator to supply power to temperature sensor 34. Positioning of the radio communication electronics 31 outside the monitored enclosure 41 ensures the integrity of wireless communications with wireless gateway 23 of nearby placed collector 20. Radio module 33 is adapted to interrogate and relay by radio the temperature measurements from temperature sensor 32, and also current battery voltage via its ADC, to assist in providing information on state of battery charge to the collector 24 relay to remote server 100, from which reporting system 301 can generate an alert if the battery voltage indicative of a need to replace or recharge the batteries. ‘ In order to enable low-power operation between reporting periods, wireless sensor node 31 is adapted to control a low- power sleep mode interspersed with periodic wakeup events when radio module 33 retrieves a current temperature from temperature sensor 32 and the current battery voltage from its on-board ADC.

This information is sent as the payload to wireless gateway 23 of data collector 20. Radio module 33 then waits for an acknowledgement and instruction from microprocessor 24 via wireless gateway 23 regarding how long to sleep until the next reporting interval. Radio module 33 will retry transmission if unsuccessful up to 3 times before abandoning. By programming microprocessor 24 to instruct the wireless sensor node 31 on the next sleep period, data collector 20 can maintain synchronisation of reporting periods while still allowing the wireless sensor node 31 to operate in a low-power sleep mode as much as possible.

Data collector 20 is controlled by the microprocessor 24 built around a 400 MHz ARM processor running Linux as its operating system. Data collector 20 is installed at the site in close range to temperature sensing those 30 and 31. Wired range or wire sensor node 30 is typically 3 to 10 m and wireless range of radio transmitter 33 in wireless sensor node 31 is typically to 20 m. Microprocessor 24 is programmed to communicate via wireless gateway into and through radio module 33 of wireless sensor node 31 following the basic package definition for the Semtech SX1231 transceiver. 3G modem 25 provides communication capability of data collector over a mobile telephone network to an Internet service provider for on connection to communications interface 20 of the remote server. Data collector 20 may be programmed to periodically initiate communications with the remote server to transmit data, or to transmit data in response to a request from the remote server, as described above in relation to low-power sleep mode or otherwise. Further, the remote server may more generally be programmed to send commands to data collector 20 for configuration or diagnostic purposes in relation to the sensors.

It will be appreciated that the system of the invention enables superior monitoring of environmental parameters distributed over a number of clients, sites and sensors. By designing the system such that the data collectors are essentially “dumb transmitters” which primarily collect and transmit to a remote server the actual environmental measurements, the remote server can be used to control and maintain integrity of the environmental monitoring, preventing the possibility of undetected degradation and/or failure of the monitoring. Further, the centralised gathering of the environmental data enables sophisticated reports to be provided to the client and the centralised report subsystem increases the reliability of the alert generation and delivery.

Persons skilled in the art will also appreciate that many variations may be made to the invention without departing from the scope of the invention, which is determined from the broadest scope and claims.

For example, while the communications interface is described as functionally separate from report subsystem, the report subsystem may physically be located at the same location or in the same computer as the communications interface, or the communications interface may be distributed physically over a number of locations. Further, the types of communication link are exemplary only and all types of communication link are within the scope of the invention. Further still, the measured values of environmental parameter may be transformed before transmission, such as from degrees Fahrenheit to degree Celsius, or to reduce the decimal point accuracy, or other transformation which still realistically enables interpretation at the remote server of the environmental conditions, while still coming within the scope of the invention. Further also, the various aspects of data, server and other redundancy described above are desirable only and systems without redundancy are within the broadest scope of the invention.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

Claims (16)

1. A system for monitoring of one or more environmental parameters measured at one or more sensors located at a plurality of sites, the system comprising one or more data collectors at each site communicating with a remote server, wherein: the data collectors at each site are adapted to collect and store values of the environmental parameters measured by associated ones of the sensors at measurement times, and to communicate the values to the remote server; and the remote server comprises a communications interface to interact and communicate with the data collectors and with users of the system, a database to store the values of the environmental parameters and a reporting subsystem to generate reports and alerts for designated ones of the users.

2. The system of claim 1, wherein the reporting subsystem generates alerts according to excursions of the measured values of the environmental parameters above or below one or more limits.

3. The system of claim 2, wherein the limits are set by authorised ones of the users for each sensor at each site.

4. The system of claim 2, wherein the reporting subsystem generates alerts only after the excursion has continued for more than an alert wait time.

5. The system of claim 2, wherein the alerts are communicated to the designated ones of users by SMS, email or other mode of electronic communication according to a recorded preference.

6. The system of claim 1, wherein the environmental parameters include temperature of an enclosure.

7. The system of claim 1, wherein the data collectors are also adapted to collect and store values of a battery voltage of one or more of the associated sensors which are powered by battery.

8. The system of claim 7, wherein the reporting subsystem generates alerts when the battery voltage of a sensor falls below a limit indicative of the need to replace or recharge the battery of the sensor.

9. The system of claim 1, wherein the data collectors are also adapted to collect and store the measurement times and communicate the measurement times to the remote server.

10. The system of claim 1, wherein the reporting subsystem generates alerts when a data collector fails to communicate values as scheduled from one of its associated sensors or when a data collector communicates to the reporting subsystem concerning a communications fault with one or more of the associated sensors.

11. The system of claim 1, wherein the reporting subsystem is adapted to generate a report for each site, the report comprising a history of stored values and measurement times received by the remote server.

12. The system of claim 1, wherein the communication between the data collectors to the remote server comprises redundancy in the case of communications failure, including multiple DNS server addresses.

13. The system of claim 1, wherein the communication between the data collectors to the remote server proceeds via a digital mobile telephone link from this data collector to an Internet provider.

14. The system of claim 1, wherein the database comprises redundancy in the case of failure or inaccessibility of a data storage medium, the redundancy comprising two replicated database machines in relative geographical proximity but isolated in terms of power supply, Internet connection and cooling.

15. The system of claim 14, further comprising additional redundancy in the form of a backup server which can be used as a recovery point in the case of complete system failure.

16. The system of claim 1, wherein power consumption is reduced in battery-powered wireless ones of the sensor units by the associated data collector periodically communicating a sleep time to said sensor units after receipt of data, and said sensor unit switching to a low-power sleep mode for the sleep time.