GB2579610A

GB2579610A - Gully sensor

Info

Publication number: GB2579610A
Application number: GB1819906.7A
Authority: GB
Inventors: Bello Roberto; Rymer Ashley; Silvey Thomas
Original assignee: Map16 Rsb Tech Ltd
Current assignee: Map16 Rsb Tech Ltd
Priority date: 2018-12-06
Filing date: 2018-12-06
Publication date: 2020-07-01
Also published as: GB201819906D0

Abstract

A gully sensor 10 comprises a plurality of spaced float sensors 12, 14, 16 for positioning on a gully wall 23 at different heights, for detecting a corresponding plurality ofpredetermined water levels within the gully. The gully sensor 10 can be used to identify a normal operational water level, a high water level and a flood condition, the sensors 12, 14, 16 remitting sensed data from the sensors periodically to a web server via a wireless network for enabling on screen gully condition monitoring.

Description

GULLY SENSOR

The present invention relates to gully sensor and particularly but not exclusively to a sensor suitable for mounting in a roadside gully for detecting water level and debris.

BACKGROUND TO THE INVENTION

Roadside gully cleansing is currently conducted at regimented time intervals based on historical knowledge of how a particular drainage network performs. This approach represents a best guess, taking into account, for example, rainfall and falling leaves.

However, this is inefficient, because clean gullies can be unnecessarily cleaned and clogged gullies can be neglected. This lack of targeted cleaning leads to excessive costs in plant and man power. It also increases the risk of flooding in high risk areas, due to the failure to clean a proportion of blocked gullies. In the winter months, there is increased risk from fallen leaves and generally higher rainfall. The need for cleaning resources is high and local councils are under pressure to reduce the cost of all maintenance activities.

The idea of using a sensor in a gully to remotely monitor the state of a gully has previously been considered, but the sensors themselves are not well developed.

Typically, they may rely on a light detector, which determines the turbidity of water in the gully. Turbidity can be used to measure the quality of water and a reduction in water quality suggests a flooding risk. Put another way, if there are more suspended solids from debris in the water, then it has a higher turbidity and the risk of flooding is increased. However, this alone does not provide sufficient information as to, for example, the water level in the gutter, which may indicate not only high flow, but also a blockage.

It is an object of the present invention to provide a gully sensor which reduces or substantially obviates the aforementioned problems.

STATEMENT OF INVENTION

According to a first aspect of the present invention there is provided a gully sensor comprising a plurality of spaced float sensors for positioning in a gully at different heights, for detecting a corresponding plurality of predetermined water levels within the gully.

By providing spaced sensors, the varying depth of water in a gully can be monitored.

The float sensors may each be connected to a sensor unit. A processor (or CPU), battery and an antenna or antennae may be provided at the sensor unit for relaying sensed data from the float sensors to a network or remote monitoring station.

By connecting the sensors to a wireless network, data from the sensors can be monitored via a web portal.

A light sensor may be provided on the sensor unit. Advantageously the light sensor can monitor changes in light in the gully and it is possible to determine if a vehicle is parked over the gully or if fallen leaves are covering the gully grating, and so avoid arranging for gully cleaning when access is restricted.

A solar panel may be mounted to the sensor unit for topping up the battery. There may be several batteries forming a battery pack, which may be rechargeable. The solar panel may also be used to detect fallen leaves or parked vehicles through a voltage drop in the solar cells.

A mounting plate may be attached to the sensor unit. This provides a means of attaching the sensor unit to the gully wall in substantially any suitable orientation and position.

The sensor unit may be waterproof The sensor unit being sealed against water and particulate ingress is important, particularly in flood conditions when the sensor unit may be entirely submerged.

An elongate member for attachment to a gully wall may hold the sensors in predetermined spaced positions. The elongate member may be hollow and may also serve as a cable guide. Advantageously the elongate member may be used to position sensors, for example, at a normal water level, a high water level and a flood condition.

Also, the positions of the sensors on the elongate member can be altered to fit a specific gully.

A clamp may be provided for connection to the elongate member and the gully wall. This enables straightforward fixing and adjustment of the sensor heights by movement of the elongate member.

There may be three float sensors, although it will be appreciated that two sensors may be sufficient in smaller gullies and systems. In larger gullies, more than three sensors may be desirable.

The float sensors may operate in a binary or on/off manner, indicating whether they are floating or not. The threshold for this condition may be determined by a tilt switch, for example.

The spacing between adjacent float sensors may be greater than the distance between each of those float sensors and the elongate member. For example, if the float sensors are connected to the member via cables, the length of the cables may be less than the spacing of the float members to avoid the float sensors becoming tangled in low water level conditions.

The sensor unit may be adapted to transmit sensor data from one or more of the float sensors at particular time intervals. The time interval is preferably selected to prolong the power reserves in the device. For example, daily transmission may be sufficient in summer conditions. The processor may determine whether data is to be transmitted more frequently when the solar panel is charging the battery. Data may be transmitted at more frequent intervals when at least two of the float sensors are floating (that is, when the gully water level is above normal).

According to a second aspect of the invention there is provided a method of monitoring one or more gullies in a drainage network using a plurality of gully sensors according to the first aspect of the invention, comprising fitting each gully sensor in a gully with sensors positioned at different heights in the gully for identifying different water level conditions, for example, a normal operational water level, a high water level and a flood condition, the sensors remitting sensed data from the float sensors periodically to a web server via a wireless network for enabling on screen gully condition monitoring.

The wireless network may utilise sub-gigahertz radio frequency bands, which can for example avoid interference with other wireless networks, and the data may be transmitted as radio frequency packets, which are converted to IP packets. The advantage of using low frequency bandwidths is that the transmission power is very low, reducing the service intervals on the gully sensor, for example, for changing batteries. The solar panel mounted to the sensor unit may top up the energy of the batteries.

The sensed data may be encrypted during transmission over the wireless network.

The method may include the step of monitoring or reviewing data from one or more gully sensors for assessing the rate of drainage from one or more gullies, for example after prolonged or heavy rainfall. This can be used to determine whether a particular gully is partially or fully blocked. If used in conjunction with a gully network map, it can also be used to infer whether sections of the gully network linking two or more gullies are likely to be partially or fully blocked, or damaged in a way that affects drainage between gullies. Maintenance work can be planned accordingly.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example only to the accompanying drawings, in which: Figure 1 shows an embodiment of a gully sensor of the invention; Figure 2 shows the gully sensor of Figure 1 in position in a drain; and Figure 3 shows the internal components of the main sensor housing.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring firstly to Figure 1, a gully sensor is indicated generally at 10. The gully sensor 10 includes a plurality of float sensors arranged in a line which can be disposed within a vertical part of a drain. This enables the water level to be detected within the drain.

The number of float sensors and their vertical spacing determines the water level measurement resolution and the number of sensors and their spacing can be selected according to the gully being monitored. In the embodiment shown, there are three float sensors, a lower sensor 12, a middle sensor 14 and an upper sensor 16. Each sensor 12, 14, 16 is an independent float sensor connected to a sensor unit 18 by a respective cable.

The float sensors 12, 14, 16 are ideally spaced from each other by a distance which avoids the cables tangling when the water level is below normal and none of the floats is in the water. The cable length may be selected in conjunction with the expected float sensor spacing to address the same issue.

A cable housing 20, in the form of a hollow tube, ideally a plastic conduit, can be secured to a gully wall and the sensors 12, 14, 16 are spaced along the housing. For example, a connecting cable 12A for the lower sensor extends from the sensor 12 to the housing 20, runs through and out of the upper end of the housing 20, and into the sensor unit 18. There is a piece of the cable 12A, say around 150mm in length, which runs between the sensor 12 and the cable housing 20, and this allows the float sensor 12 to be able to move its position and orientation relative to the cable housing 20, which in use is fixed to a gully wall. The other sensors 14 and 16 are arranged in a similar manner, providing for limited mobility of the sensors. As shown in Figure 2, the cable housing 20 can be clamped to a gully wall using a clamp 22, which is screwed or otherwise fastened to the gully wall 23.

The length of the cable housing 20 can be changed, as desired, to suit gullies of different depths. Apertures in the side of the cable housing accept the sensor cables 12A, 14A and 16A, and the position of these apertures can also be used to adjust the height of the sensors relative to one another and the cable housing. Each cable housing may be pre-drilled with extra apertures to enable changing of the sensor positions, as required.

Referring also to Figure 3, the sensor unit 18 includes a waterproof enclosure 24, for example, a stock CE-TEK 1P68 enclosure. The cables 12A, 14A, 16A are let into the enclosure 24 through watertight connectors 26, for example IP68 cable glands. The cables terminate at a PCB 28 located within the enclosure. An antenna 30 is secured to the top of the enclosure 24 for wirelessly connecting the sensor to, for example, a low power, wide area network (LPWAN) or mobile telephone network.

The sensor is powered by a battery pack, indicated at 32 (batteries excluded from the Figure). The batteries are preferably rechargeable. A light sensor 34, Figure 2, is mounted to an external surface of the enclosure. The light sensor is typically a light dependent resistor, which is capable of detecting loss of light due to falling leaves covering the gully and a car parked above the gully. A solar panel (not shown) may also be mounted to an external surface of the enclosure for charging the batteries. This reduces maintenance of the gully sensor 10, particularly because the batteries do not need replacing so often.

A mounting plate 33 is connected to the enclosure 24. Apertures 35 through the plate 33 allow the enclosure to be mounted to the gully wall 23 above the cable housing 20, typically using screws.

In use, the gully sensor 10 is mounted in a drainage gully, for example, as shown in Figure 2. The sensor unit 18 is mounted proximate the top of the gully, underneath the drainage grating 36. The cable housing 20 is attached to the gulley wall by the clamp 22, with the cable housing extending substantially vertically downwards. The sensors 12, 14, 16 are then spaced vertically inside the gully. As can be seen in Figure 2, one sensor is submerged, one is floating and one is hanging on its connecting cable.

The status of the float switches is output wirelessly at a set time interval via the LoRaWAN networking protocol to the closest gateway. The data is then sent via GSM mobile network to a LoRaWAN network server from which the data is transferred via HTTPS integration to an asset management web dashboard. This enables the gully water level to be monitored. Furthermore, the light sensor can determine if the gulley is blocked with leaves, or if a car is parked over the gulley. The use of LoRaWAN technology allows the long-range transmission of data with extremely low power requirements. This allows the use of AA batteries and a relatively small enclosure 24.

It will be appreciated that the data collected can be used to schedule cleaning of the gully, only when cleaning is required. The availability of live (or near real-time) data allows key decision makers to react to changes in gully network conditions to prevent flooding. The data collection aspect also allows conclusions to be made about the state of the network, including estimating silt levels to facilitate preventative actions. A primary aim of the device is to streamline the gully cleansing model and to improve efficiency through targeted cleaning regimes.

The robust nature of the gully sensor 10, by virtue of its design, makes the device extremely durable and able to cope with significant impacts from gully suction nozzles.

It is also waterproof and reliable, not relying on a light sensor to detect depth of water, which is somewhat unreliable.

The light sensor is only for the purpose of measuring the light level inside the gully to establish if the upper grating is obstructed by biological matter (leaves), or a parked vehicle. This will allow the seasonal deployment of personnel to clear the biological matter if the gully is known to be close to tree or vegetation cover. If the gully is in an area free from tree cover, or at a time of year where leaf cover is not prevalent then it is likely the obstruction is from a parked vehicle. Knowing the parked vehicle data will make the gully cleansing process more efficient as customized live route plans can be used to ensure personnel don't visit gullies that cannot be accessed.

The embodiments described above are provided by way of example only, and various changes and modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims

CLAIMS1. A gully sensor comprising a plurality of spaced float sensors for positioning in a gully at different heights, for detecting a corresponding plurality of predetermined water levels within the gully.
2. A gully sensor as claimed in claim 1, in which the float sensors are each connected to a sensor unit.
3. A gully sensor as claimed in claim 2, in which a processor or CPU, battery and at least one antenna are provided at the sensor unit for relaying sensed data from the float sensors to a network.
4. A gully sensor as claimed in claim 2 or claim 3, in which a light sensor is provided on the sensor unit.
5. A gully sensor as claimed in any one of claims 2 to 4, in which a mounting plate is attached to the sensor unit.
6. A gully sensor as claimed in any one of claims 2 to 5, in which the sensor unit is waterproof
7. A gully sensor as claimed in any preceding claim, in which an elongate member for attachment to a gully wall, holds the sensors in predetermined spaced positions.
8. A gully sensor as claimed in claim 7, in which the elongate member s hollow and serves also as a cable guide.
9. A gully sensor as claimed in claim 7 or 8, in which a clamp is provided for connection to the elongate member and the gully wall.
10. A gully sensor as claimed in any preceding claim, in which there are three float sensors.
11. A gully sensor as claimed in any preceding claim, further comprising a solar panel.
12. A method of monitoring one or more gullies in a drainage network using one or more gully sensors as claimed in any preceding claim, comprising fitting each gully sensor in a gully with sensors positioned at different heights in the gully for identifying different water level conditions, the sensors remitting sensed data from the sensors periodically to a web server via a wireless network for enabling on screen gully condition monitoring.
13. A method as claimed in claim 12, in which the wireless network utilises subgigahertz radio frequency bands.
14. A method as claimed in claim 13, in which the data is transmitted as radio frequency packets, which is converted to IP packets.
15. A method as claimed in any one of claims 12 to 14, in which the sensed data is encrypted during transmission over the wireless network.
16. A method as claimed in any of claims 12 to 15, including the step of monitoring or reviewing sensor data from one or more of the gully sensors for assessing the rate of water drainage from one or more of the gullies.