COMMUNICATIONThis invention relates to the communication of information between a sensing transducer and a central processing and/or recordal and/or control facility. The invention finds particular application in relation to flow systems such as supply and collection systems, particularly, but not exclusively, fluid, for example water and sewage supply and collection systems, and gas, electricity and like flow systems.
Heretofore, it has been difficult, if not impossible, in some fluid collection/distribution systems, economically to apply sufficient monitoring and measuring installations systems to allow them to be managed efficiently. This applies particularly at the branch end of a tree-type system.
Whilst it has always been desirable that various parameters of the system could be measured at many spaced positions, the inherent costs of individual sensors and the cost of sending such information to a sensor facility has been prohibitive. In fact, due to the fact that in water supply systems in particular the conduits are often in remote areas, the cost of providing power to individual sensors is so costly that such sensors are only provided when absolutely necessary. Solar powered sensors have been used, but again they are costly and prone to damage, and cannot be used in some situations.
It is an object of the present invention to improve a distribution flow system. The phrase flow system can mean either a distribution or a collection system.
According to the invention there is provided a monitoring installation for use in combination with a conduit, the installation including an enclosure, a sensor adapted to be arranged and mounted in a position to monitor paramemeters of the conduit and/or its contents, a power source and a transmitter within the enclosure, a part of the enclosure being arranged to function as an antenna to diffuse signals from the transmitter.
In the following description, the word "antenna" is used to mean "antenna or transducer, or any other means of wireless communication"The antenna is preferably substantially at ground level.
A controller may be provided between the sensor and the transmitter to convert signals produced by the sensor into a form suitable for transmission and to add, if necessary, identifying origin addesses thereto. The controller may also be adapted to add desired destination addresses to the signals. The form suitable for transmission may be a digitial form.
The antenna may be formed by a closure of the enclosure. The closure may be in the form of a manhole or inspection chamber or comparable enclosure cover. The antenna may be mounted on or incorporated in the closure.
The closure may include or consist of non-electrically conductive material.
The transmitter may be adapted to transmit data digitally. The transmitter may transmit data by radio or any comparable radiation. The transmitter may be a conventional radio.
The power source may be a solar panel or comparable supply. It is desirably a battery incorporated within the installation. Desirably the power requirements of the electrical portion of the installation is low so as to give a battery minimum life of one year, preferably two or three years.
Battery condition can be included in the data transmitted to the base stations.
The antenna may be an aerial. The antenna may be a loop antenna, a phased array slot antenna or any other suitable antenna. The antenna may be an omni-directional antenna or a uni-directional antenna or a bi-directional antenna. An omni-directional antenna has a range shorter than a uni-directional antenna of the same power. Whichever is chosen will depend on the geography of a system within which the closure is to be used.
For an omni-directional antenna a simple loop antenna can be incorporated. For a uni-directional antenna a phased-array-slot antenna can be used, one or more of the elements being driven.
According to the invention there is also provided a flow system including a plurality of conduits, a plurality of spaced apart base stations capable of sending data to a central facility, a plurality of monitoring installations of the invention arranged and mounted in positions to monitor parameters of said conduit, wherein the transmitter of the monitoring installations are adapted to transmit data to one or more of said base stations.
Desirably, said data is transmitted ditigally.
Data can also be transmitted to the base stations and to the installations.
This can be effected by the sensor generating signals which are passed to a controller which converts them into a form suitable for transmission, for example by converting them to a ditigal form (if the transducer produces an analog signal) adding an identifying origin address and possibly a desired destination address and then passing the signal to the radio for transmission via an antenna or transducer or any other means of wireless communication.
The closure can be in the form of a manhole cover adapted, if necessary, to seal an enclosure in the form of a conventional "manhole" the word manhole includes inspection chambers and all comparable enclosures). The antenna can be fitted to the frame of the manhole cover or embedded in the surrounding ground.
The antenna could be generated by manufacturing a manhole cover out of conventional cast iron, wrought iron, steel or like materials and incorporating slots therein surrounded by steel, which slots act in the nature of a antenna, and are insulated from the remainder of the cover.
The cover can be intrinsically of a non-electrically-conducting material and can have the antenna incorporated upon or within the material of the cover. An antenna can provided by securing metal structure to the top of the cover. Another possibility is to embed antenna-constituting members within an upper layer of the cover. This could be done in a moulding process by laying the antenna-forming element(s) in a mould and then adding other components of the cover.
The antenna-forming elements could be continuous metal or metal impregnated plastics, for example, plastics material containing metal powder.
The cover is desirably manufactured from fibre reinforced settable material. The settable material can be a cement or can be a plastics material. For example, the cover can be made of concrete or of plastics material and in either case a fibrereinforcement can be incorporated. In the case of a cement based settable compound the reinforcement can be polyproylene webs, mats, batts or fabrics.
In the case of a plastics reinforced material reinforcements can be carbon fibres, glass fibres, plastics fibres of many sorts, or aramid fibres such as those sold under the Trade Mark KEVLAR.
When the closure includes or constitutes a directional antenna it is desirable that the relationship between the closure and its seating is such that the orientation of the closure can be selected and, thereafter, always replaced in the same orientation after removal. This can be arranged by having detent/recess means spaced around the cover and/or its seating, at least one of said detent/recess means being selectively placeable in an operative condition. For example, the cover can have a pin, and the seating can be provided with a plurality of frangible areas angularly spaced around its periphery one of these areas being selected upon installation and the pin always, thereafter, engaging in that location to orientate the cover. It will be appreciated that in these circumstances the cover should be circular or at least polygonal with such a large angle that the cover can be orientated.
The invention will be described further, by way of example, with reference to the accompanying drawings wherein:Fig. 1 is a very schematic sketch illustrating, in the barest outline, a preferred flow system in accordance with the invention;Fig. 2 is a vertical cross-section through a preferred installation of the invention;Fig. 3 is a planned view illustrating a possible construction of cover;Fig. 4 is a sketch illustrating power transmission lobes of a slot antenna within a cover;Fig. 5 is a plan view of a further possible cover;Fig. 6 is a cross-sectional view on the linesVI-VI of Fig. 4;Fig. 7 is a cross-sectional view on line VII-VII of Fig. 5 illustrating antenna power lobes;Fig. 8 is a cross-sectional view on lineVIII-VIII of Fig. 3;Fig. 9 is a cross-sectional view illustrating a further possible construction of cover;;Fig. 10 is a vertical cross-section illustrating a further possible cover; andFig. 11 is an underneath plan view of the cover of Fig. 10.
Referring firstly to Fig. 1 there is shown, as a sketch and only in broad schematic representation, a preferred flow system 10 of the invention. The system 10 is shown as being a flow system being distributing water from a reservoir 11 via a trunk main 12 to various branch mains 13 and eventually to consumers 14.
It should be said that the system of the invention does not need to relate to water supply.
The system can relate to any flow of fluid within a conduit system, or the flow of electricity in distribution cables. As well as covering a distribution system as shown, the flow system of the invention can also be a collection system, again for any material flowing in a factory or process, for example in a chemical factory or oil refinery, or could be a sewage collection system wherein the arrangement would be essentially the reverse of that shown in Fig. 1.
Referring now specifically to the system shown in Fig. 1, it will be seen that valves 15, all indicated by the letter V are provided throughout the system and adjacent each consumer 14 (also indicated by the letter C) is provided a monitoring installation 16 (also indicated by the letter M) which is in accordance with a further aspect of the invention. Comparable monitoring installations are provided throughout the system.
The system also includes a plurality of base stations 17 of which two are shown and also indicated as B2 and B1. The base stations 17 are connected by a link 18 indicated in chain dotted lines to a central processor 19. The link 18 can be a hard wired or a telecommunication link. The central processor 19 can be or can incorporate a computer at a headquarters or like monitoring facility where the performance of the entire system can be overseen.
Each monitoring installation (as will be later described in more detail) has a self-contained transmitter and an antenna which is directed towards one of the base stations 17. In the sketch the orientation of an aerial is indicated by a small arrow attached to the monitoring installation 16. In practice, the orientation of the antenna of each installation 16 may be towards the nearest base station 17, or to that of the adjacent base stations which gives the best signal reception.
The system of the invention is relatively cheap because mains power does not have to be provided to each monitoring installation, (although it can be in cases where mains is relatively close and easily accessible) nor does an individual telecommunication link or hard wiring have to be provided from each individual monitoring installation to a central facility. The individual monitoring installations are relatively cheap, and their aerials cannot easily be damaged. Their information can be collected easily by the base stations and thence transmitted to the central processor. The present invention allows a much closer monitoring of such a flow system than has hereto always been possible and at a cost which is not excessive.
The base stations can, in fact, be part of a system which hhas other functions. For example there are, at present, several systems which operate at certain frequencies to receive and re-transmit telephone calls between users. There will soon be a network of such "phone points" throughout many areas of the country and it is envisaged that such existing base stations could be used to carry the information from the various monitors to a central processing location. The using of existing base stations does, of course, have great cost advantages both to the user of the base station and to the owner of the base station. The information from the monitors can operate at frequencies different from the telephone used frequencies, or can be allotted a section within the range.In many cases, for example, in the case of the monitors 16 which are adjacent consumers, and which can monitor volume use of a supply commodity such as water, the system could be arranged to operate only at night when the telephone use is small, enabling remote meter readings to be effected.
Referring now to Fig. 2, it will be seen that a preferred installation 16 of the invention has an enclosure 20 in the form of a manhole or inspection chamber closed by a cover 21. The installation 16 is arranged adjacent a conduit which is shown in the form of a pipe 22 conveying drinking water 23.
The installation 16 includes a sensor indicated at 24 which sends parameters of the pipe 22 and/or of the water 23. Although pipe conditions can be important (for example temperature and stress) it is most likely that it will be the conditions of the water which will be measured. Typical parameters could be rate of flow, pressure, pH, and residual chlorine content. Of course, the range of parameters which can be measured is limited only by the size and nature of the sensors which can be provided.
The sensor 24 is connected by a lead 25 to a controller 26. The controller 26 is operative to convert analog signals from the sensor into digital signals and also to add a destination address and an origin-identifying address to the data. The controller 26 can also hold data and only send it to a radio 27 for transmission at pre-selected times. For example in a shared base station network it could be arranged that data from the various installations is transmitted only during a certain fraction of each minute. Alternatively the installation could be individually triggered, from a base station, to transmit data held in the controller. A further possibility is that each installation could be internally triggered to transmit at random intervals, thus evening the load on the communication network.
The controller 26 and radio 27 are powered by a battery 28 and it is expected that the sensor controller and the radio system will be chosen so that the battery has a life of at least one year and desirably two to to three years or more in order to minimise maintenance costs. Battery condition information can, of course, be sensed by the controller and included in the data transmitted if desired.
From the radio 27 a signal is passed via a lead 29 to an antenna which is in the form of metallic element 31 incorporated within a non-electrically conducting cover 21. the cover 21 can have varying forms as will be later described.
Figs. 3 and 8 show one possible way of creating a cover which, in accordance with a further aspect of the invention, incorporates or consists of a transmitting antenna. In these Figures a cover 32 is circular and has a portion 33 made of metal, for example cast iron or steel, and slots in the steel are filled with a load bearing plastics material 34 or some other non-conducting material such a concrete. By providing loops of conducting material (not shown) surrounding slots and insulated from the remainder of the cover, this cover 32 can then operate as a phased array or other slot antenna.
Figs. 4 and 6 illustrate a further form of cover 35. The cover 35 includes a body which is of non-conducting material whose nature is not relevant to this particular feature and will be described further at a later stage. Within the material of the cover 35 are embedded three elements 36 which are in the form of metal rods, or metal particles, such as powder embedded in a plastics matrix. One or more of the metal elements 36 is driven from the radio transmitter and generates a signal which has a distinct large power lobe 37. Such a cover 35 will normally be orientated with its lobe 37 directed towards a base station 17 in the system 10.
Figs. 5 and 7 illustrate further possible embodiment of cover 38 which again is of a non-electrically conductive material and which has a circular metal elements 39 embedded therein. As Fig.
7 shows the circular elements 39 constitutes an antenna which has a doughnut-shaped lobe 40. Such an antenna is omni-directional. It has a lower range than a uni-directional aerial of the same power.
Fig. 9 shows a cover 41 which again is made from non-electrically conductive material. Here instead of having metallic elements buried within the cover, metallic elements 42 are provided in the surface material of the cover. Such elements 42 can be of metal, or of metal-powder-impregnated plastics or concrete and can be incorporated in the cover by placement in a mould prior to the addition of other materials.
It is expected that the non-electrically conducting manhole cover such as cover 21, 35, 38 and 41 will be made from a settable material with reinforcement. A metal cover reinforcement constituting an antenna can be sufficient. Steel reinforced concrete could be suitable. Fibre reinforced settable material can also be used.
In the case of a cement based settable material it is expected that a terylene-, nylon-, or polypropylene-, reinforced concrete material would be suitable, metallic elements and their associated lead(s) be incorporated during moilding of the cover.
In relation to plastics materials, it is expected that acrylic or other plastics could be suitable. As reinforcement, nylon, polypropylene other plastics material, carbon fibre or aramid fibres such as those sold under the Trade Mark KEVLAR could be used for reinforcement in the form of batts, mats, fabrics or other separate fibres.
In the case of covers which have to bear significant loads from vehicles, the construction of a non-metallic cover having the appropriate strength at reasonable costs is somewhat problematical. Figs. 10 and 11 illustrate one possible solution, wherein a cover 43 made from fibre reinforced plastics material has a relative thin main disc 44 wherein are embedded antenna elements 45. The disc is integral with a plurality of radial ribs 46 which support the main disc. The ribs 46 can be attached to a central boss 47.
As has been discussed earlier, the invention includes the flow system, the monitoring installation and the closure for the monitoring installation.
The invention is not restricted to the precise details of the foregoing, and variations can be made thereto.
For example, the closure to the installation does not necessarily have to be a manhole cover. In the case of installations which, for example, are above ground, the closure could be a door or the like. The system can be a collection and/or a distribution system for a wide number of fluids including gas and electricity. It is expected, however, that it will be most useful in relation to water supply and sewage collection, and comparable functions within industrial plants such as chemical plants and/or refineries.
Any convenient antenna arrangement can be provided in the closure other than the'ring antenna and the (phased-array) slot antenna disclosed.
As mentioned, transmission can occur not only from but to the installations, the antennae serving as receiving antennae. The installations can be instructed to transmit. The sensor operation can be modified, or controller. May other control functions can be included.
The invention allows a very precise and real-time monitoring and/or control of a flow systems, particularly of a tree-type system, at its branches.
Many other variations are possible within the scope of the invention.