Sensor system

Abstract

A wireless sensor system 2 including at least one sensor device 4, said sensor device including a transmitter apparatus, at least one sensor apparatus and a processor unit characterised in that the tr

Description

The present invention relates to wireless sensor devices as well as methods of producing and constructing the same. Although the present description refers to temperature sensors, the person skilled in the art will appreciate that the present invention can be used with other sensors, such as movement sensors, or combinations of sensors and is not limited exclusively to temperature sensors. Conventionally, sensing devices and associated data loggers are used to monitor and record various environmental conditions in equipment such as incubators, refrigerators, freezers, and food display cabinets. These sensing devices / data loggers typically require hard-wired electrical connection to external equipment for data retrieval. Proprietary wireless devices are available but calibrated wireless sensors are expensive to implement and maintain. Another drawback of current data logger is the necessity for specialised peripheral equipment in order to communicate with the logger sensor and for retrieving and processing the data. Transmitters in the form of Bluetooth™ Low Energy (BLE) devices that broadcast their identifier to nearby portable electronic devices are known. This technology enables electronic devices to perform actions when in close proximity to a beacon. BLE beacons transmit a universally unique identifier picked up by a compatible app or operating system and can therefore be used as proximity sensors. The identifier and several bytes sent with it can be used to determine the device’s physical location, track customers, or trigger a location-based action on the device and / or a push notification generated from a central server. The standard beacon signal includes the manufacturer, a device name (which may be unique), as well as a unique hardware address and codes to identify the type of device and the functions it offers. Furthermore, there is area of the signal that is not visible to most mobile apps. It is an aim of the present invention to provide an improved sensor system that addresses the abovementioned problems. In a first aspect of the invention there is provided a wireless sensor system including at least one sensor device, said device including a transmitter apparatus, at least one sensor apparatus and a processor unit characterised in that the transmitter apparatus is configured to emit low powered signals that contain sensor readings and / or data output from the sensor apparatus. Typically the signals are periodic low powered signals. In a preferred embodiment of the apparatus the transmitter apparatus is a Bluetooth™ Smart or BLE transmitter. Typically the sensor apparatus readings and / or sensor apparatus data output is included in the hidden area of the signal. Further typically system includes a plurality of sensor devices. As such, the sensor devices of the system are beacons with one or more sensors that emit a beacon signal that includes the sensor readings, preferably in the hidden area of its signal. In one embodiment of the invention the sensor apparatus includes a temperature sensor. Typically the temperature sensor apparatus is calibrated. Further typically the temperature sensors are precisely calibrated to ISO17025. Typically the sensor apparatus is calibrated before being incorporated into the device. In one embodiment of this application, the processor unit periodically wakes and measures a parameter via the sensor apparatus. Typically, if there is any change in the parameter, the processor changes a data section, or the data section of the signal. Typically the device includes a battery power source. Further typically the power source is a coin cell. In one embodiment the system includes a data aggregator apparatus. Typically the data aggregator monitors or reads the signals from a plurality of sensor devices. In one embodiment the data aggregator apparatus is connected to the Internet and / or a cellular TOT service provider. Typically the device readings are forwarded or sent to a remote server or cloud server. In a preferred embodiment the data aggregator apparatus is a cellular device. In one embodiment the system includes an array of devices. In one embodiment the system includes a linear array or length of devices on a support member. Typically such devices can be used as liquid level monitors, for liquid nitrogen and / or the like. In a second aspect of the invention there is provided method of constructing a wireless sensor system including at least one sensor device, said device assembled or configured to include a transmitter apparatus, at least one sensor apparatus and a processor unit characterised in that the transmitter apparatus emits periodic low powered signals that contain sensor readings and / or data output from the sensor apparatus, said method including the step of including at least part of the sensor apparatus, processor unit and / or transmitter apparatus in a housing. Specific embodiment of the invention are now described with reference to the following figures wherein: Figure 1 shows a sensor array in accordance with one embodiment of the invention; Figure 2 shows sensor with a display in accordance with one embodiment of the invention; and Figure 3 shows a beacon sensor module in accordance with one embodiment of the invention. The standard beacon signal includes the manufacturer, a device name, which may be unique, as well as a unique hardware address and codes to identify the type of device and the functions it offers. This beacon signal is generally not variable, especially in the case of consumer device. The BLE module we use may have its beacon signal changed by the processor in our smart sensor device. Furthermore, there is area of the signal that is generally not visible to mobile apps. The idea for the beacon sensor is to build a device with one or more sensors that does nothing but emit a beacon signal that includes the sensor readings in the hidden area of its signal. In this application, the smart module processor would periodically wake and measure the temperature. If there is any change in the temperature, the processor would change the data section of the beacon signal. The power requirement for this application would be very low. A standard 20 mm diameter coin cell would power a beacon sensor for well over a year. The beacon sensor system would use a dedicated data aggregator, a “black box” device, which would monitor the signals from many, nominally 1 to around 100, devices and forward the readings to a cloud server. The aggregator requires a data connection, either via the Internet or a cellular IOT service provider. Figure 1 shows such a system 2 with up to 100 beacon sensor devices 4. The range is up to 50 metres. The aggregator 6 in this example is located in a box housing with a cellular data connection. In this example power is supplied via USB and optionally has a battery backup. The beacon sensors are calibrated, typically with a working life of 12 months from activation by the customer in addition to a shelf life of up to 3 months. As such, the product is sold as a service with 12 months of monitoring data storage, customised reporting and alerts. Apps for mobile devices enable receiving and responding to alerts generated by the cloud service. The nature of the present smart sensor technology is that the sensor components are calibrated before final assembly, and it is not economical to return and / or disassemble the device for recalibration. The annual cost of the service per device is lower than re-calibrating a conventional device. The devices are therefore disposable, to be recycled with regular e-waste. Reduced transportation and logistics results in savings in terms of energy, time, expense and environmental impact. We propose to supply the aggregators initially as cellular devices, with the applicable hardware version for the region they are to be used. The technology utilises ubiquitous and readily accessible local cellular equipment that can be readily monetised as part of the pricing structure of the product affordably to ensure easy adoption. This provides a complete “plug and play” service requiring little effort and technical knowledge to set-up by the user. Our experience shows that this outweighs the cost of supporting customers who use WiFi or Ethernet connected devices, plus more immediate access to the technology. The data from the aggregators is sent to the service provider’s existing cloud service, processed and stored in our database. Customers may browse the data and create reports using existing reporting tools such as Microsoft Power BI. It is also possible to use APIs to access the data. Our intention is to produce various versions of beacon sensors for different applications and markets. The hardware is inexpensive to produce and could be included with additional indicator devices. Specific products and applications are as follows: Pharmaceutical refrigerator / freezer monitor: Pharmacies and vaccination centres are required to have precise and continuous refrigerator monitoring. Very few of them do as the cost of existing solutions is prohibitive. Many collect the data manually, once or twice a day, with a temperature probe, paper and pen. The beacon sensor solution will be the replacement, at a much lower price, more reliable, continuously monitoring and greatly reduced human error. Figure 2 shows an example where the sensor 4 includes an external display 10. This device may be fitted to any refrigerator and the display can visually indicate whether the temperature is within a desired range and / or alert the user is it is outside the desired range. Liquid nitrogen level monitor: Genetic material such as sperm, eggs and embryos, for humans and livestock, is stored in vacuum insulated containers known as Dewar flasks under liquid nitrogen at substantially -196 °C. These containers are subject to failure (loss of vacuum) which will result in destruction of the contents unless detected early. The present system provides an early warning to Dewar container failure. The assisted reproduction industry is growing quickly. Labs are addressing the need for more storage by buying more Dewars. Each Dewar needs to be periodically topped up with liquid nitrogen. The usual method is to use a dipstick to determine the level of liquid nitrogen. The lab technician keeps an eye on the rate of liquid nitrogen loss and tops up the level accordingly. It is more desirable and safer to have a monitoring system that automatically monitors the Dewars. However, existing systems are expensive and inflexible. Each new Dewar needs to be fitted with a sensor and added via a wired system, which has a considerable set up and ongoing service / maintenance costs. Figure 3 shows a beacon sensor system 2 with a linear array of low-cost temperature dependent resistors 4. Each resistor gives a definitive reading as to whether it is immersed in liquid nitrogen 12 or not. By using several resistors, we get a level reading within a Dewar 14 at lower cost than using a regular cryogenic temperature sensor. Competing systems measure the temperature at one point inside the Dewar. This does not give a good indication of the level of liquid nitrogen. If the sensor is immersed in the liquid, the temperature will always be substantially -196 °C regardless of depth. If it is above the level of the liquid, the reading will be around -150 °C with no indication of the height above the liquid. The liquid nitrogen level monitor gives a real-time indication with resolution of 12 mm, or better depending on the spacing of the sensors, as required. Real time readings of the level provide early warning of possible leaks in the Dewar, which are indicated by rapidly reducing level of the liquid nitrogen. The liquid nitrogen level monitor may be produced with a range of array lengths and retrofitted to any Dewar. Warehouse and other monitoring Warehouse monitoring is a growing and lucrative field. Warehouses of all types are subject to hot and cold spots, temperature fluctuations and areas of varying humidity. Even “room temperature” products will degrade quickly if subjected to adverse conditions. The warehouse beacon sensor would be a business card / credit card sized device. A larger device provides for a longer antenna and exponentially greater range. It could provide humidity as well as temperature measurements. A low temperature variant could be made for frozen food warehouses. The warehouse beacon sensor device could be used for workplace safety. For example, we once provided sensors for use in the roof of a film studio, where sets and scenery were stored. If the temperature was unsafe, the workers could be warned against going into the area.

Claims

1. A wireless sensor system including at least one sensor device, said sensor device including a transmitter apparatus, at least one sensor apparatus and a processor unit characterised in that the transmitter apparatus is configured to emit low powered signals that contain sensor readings and / or data output from the sensor apparatus.

2. A system according to claim 1 wherein the signals areperiodic low powered signals.

3. A system according to claim 2 wherein the transmitterapparatus is a Bluetooth™ Smart or BLE transmitter.

4. A system according to claims 1-3 wherein the sensorapparatus readings and / or sensor apparatus data output is included in the hidden area of the signal.

5. A system according to claims 1-4 wherein the system includes a plurality of sensor devices.

6. A system according to any preceding claim wherein the sensor apparatus includes a temperature sensor.

7. A system according to claim 6 wherein the temperature sensor apparatus is calibrated.

8. A system according to claim 7 wherein the sensor apparatus is calibrated before being incorporated into the device.

9. A system according to any preceding claim wherein the processor unit periodically wakes and measures a parameter via the sensor apparatus.

10. A system according to claim 9 wherein, if there is any change in the parameter, the processor changes a data section, or the data section of the signal.

11. A system according to any preceding claim wherein the device includes a battery power source.

12. A system according to claim 11 wherein the power source is a coin cell.

13. A system according to any preceding claim wherein the system includes a data aggregator apparatus.

14. A system according to claim 13 wherein the data aggregator monitors or reads the signals from a plurality of sensor devices.

15. A system according to any preceding claim wherein the data aggregator apparatus is connected to the Internet and / or a cellular IOT service provider.

16. A system according to claim 15 wherein the device readings are forwarded or sent to a remote server or cloud server.

17. A system according to claims 14-16 wherein the data aggregator apparatus is a cellular device.

18. A system according to any preceding claim wherein the system includes an array of devices.

19. A system according to claim 18 wherein the array of devices is linear or in a substantially straight line.

20. A system according to claim 19 wherein the array is configured to monitor the level of a substance, liquid and / or fluid in a container.

21. A system according to claim 20 wherein the substance is liquid nitrogen.

22. A system according to claims 18-21 wherein the system includes a linear array or length of devices on a linear support member.

23. A method of constructing a wireless sensor system including at least one sensor device, said device assembled or configured to include a transmitter apparatus, at least one sensor apparatus and a processor unit characterised in that the transmitter apparatus emits periodic low powered signals that contain sensor readings and / or data output from the sensor apparatus, said method including the step of including at least part of the sensor apparatus, processor unit and / or transmitter apparatus in a housing.

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