GB2291520A - Modelling flow of moving objects and electronically identifying location of components of a network - Google Patents

Abstract

To model flow of moving objects, e.g. traffic along a road network, a plurality of component parts 10 can be connected together to represent a network along which the objects pass. At least some of the component parts represent obstacles, e.g. road junctions. Each component part has a plurality of light emitting devices 12 and control means 13 for energising them to simulate the movement of objects along the component part. The control means is responsive to a signal indicative of an obstacle in its own component part or in a part immediately downstream thereof to retard or arrest the simulated movement. The rate at which simulated objects enter the network can be controlled. A central unit can identify the location of such randomly connected component parts of a network by sending a general enquiry, the first part responding, being assigned an address, and permitting a subsequent enquiry to reach the next part, and so on. <IMAGE>

Description

APPARATUS FOR MODELLING THE FLOW OF MOVING OBJECTS & APPARATUS FOR ELECTRONICALLY IDENTIFYING THE LOCATION OF RANDOMLY CONNECTED COMPONENTS OF A NETWORK This invention relates to apparatus for modelling the flow of moving objects, such as vehicular or pedestrian traffic, and also to apparatus for electronically identifying the location of randomly connected components of a network.

Software packages are available for simulating and tuning traffic flow at, for example, a network of road junctions. These packages are, however, expensive and not designed for use by small groups, e.g. schools, or the general public.

Local people have the best knowledge of local traffic problems and in one aspect the invention seeks to provide apparatus for modelling the flow of moving objects, for example vehicular traffic, so that proposals can be put forward for improving the flow.

Accordingly, the invention, in one aspect, provides apparatus for modelling the flow of moving objects, comprising a plurality of component parts which can be connected together to represent a network along which the objects pass, at least some of the component parts representing obstacles to be encountered by the objects as they pass along the network, each component part having a plurality of light emitting devices and control means for energising the light emitting devices to simulate the movement of objects along the component part, the control means being responsive to a signal indicative of an obstacle encountered by the objects in its own component part or in a part immediately downstream thereof to retard or arrest the simulated movement of objects along its own component part, and means for controlling the rate at which simulated objects enter the network.

The means for controlling the rate at which simulated objects enter the network may be a manually adjustable variable frequency pulse generator.

Alternatively, this latter means may be an intelligent controller, such as a computer, which varies the rate at which simulated objects enter the network according to information programmed into the controller.

In a preferred embodiment of this aspect of the invention the apparatus is for modelling the flow of vehicular traffic along a road network and, in this case, some of the component parts represent road junctions and/or roundabouts which may or may not be controlled by traffic lights. In the case of component parts representing junctions and/or roundabouts controlled by traffic lights, the component parts may be provided with means for tuning the traffic lights so as to optimise the traffic flow along the network. Alternatively, where an intelligent controller is provided for controlling the rate at which simulated objects enter the network, the traffic lights may be tuned by the intelligent controller.

The component parts can be assembled together in any selected order to simulate existing or proposed road networks. Where an intelligent controller is provided, it is preferable for the controller to be able to ascertain for itself the physical layout of the component parts and configure itself accordingly. Hence, in this case, advantageously each of the component parts has a programmable logic element which can be interrogated by the intelligent controller and a solid state switch which is, in use, closed by the logic element in response to a command issued by the intelligent controller after the intelligent controller has interrogated the programmable logic element to connect the intelligent controller to the next component part in a network. In this way, it is possible for the intelligent controller to ascertain the physical layout of the component parts of the network.

Each logic element may have its own unique identity, but preferably each logic element has a type identity indicative of the type of the component part, e.g. a priority road junction or a light controlled road junction and, in this case, the intelligent controller can assign a unique identity to the logic element so that the logic element can be addressed subsequently by the intelligent controller.

Indeed, this method of identifying the location of randomly connected components could be used for purposes other than in combination with apparatus for modelling the flow of moving objects.

Accordingly, the invention, in another aspect, provides apparatus for electronically identifying the location of randomly connected components of a network, comprising a programmable logic element, which can be interrogated by the intelligent controller, in each of the components and a solid state switch which is, in use, closed by the logic element in response to a command issued by the intelligent controller after the intelligent controller has interrogated the programmable logic element to connect the intelligent controller to the next component of the network.

Each logic element may have its own unique identity, but preferably each logic element has a type identity indicative of the type of the component and, in this case, the intelligent controller can assign a unique identity to the logic element so that the logic element can be addressed subsequently by the intelligent controller.

The invention will now be more particularly described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a block diagram of the data highway of a component part of one embodiment of apparatus according to said one aspect of the invention; and Figure 2 is a block diagram of the command highway of the component part shown in Figure 1.

Referring firstly to Figure 1 of the drawings, there is shown therein a single component part 10 which can be assembled with other component parts to simulate a road network. The component parts are typically in the form of small interconnectable bricks each representing an element of a simulated road network, such as a straight section of road, a priority "T" junction, a priority crossroads, a signal controlled "T" junction, a signal controlled crossroads and roundabouts.

The road element (component part) 10 shown in Figure 1 represents a straight section of road and is provided with a data highway 11 which functions to provide traffic flow information. The data highway 11 includes a plurality of light emitting devices, typically light emitting diodes, 12 spaced apart along the length of the road element 10, a logic element 13 for controlling the light emitting diodes 12 to simulate the movement of one or more vehicles along the road element 10 and a clock pulse generator 14 for controlling the frequency at which the logic element 13 energises the diodes 12 to simulate movement of vehicles along the road element 10.

The data highway 11 is carried from one road element to another by means of a physical coupling, which may be optical for resilience, together with a low voltage power connection.

Each vehicle on the simulated road network is represented by an electrical pulse. The transfer of this pulse along a section of road is represented by the light emitting diodes 12.

A "vehicle" will only be able to pass from one road element to another if there is room for it to do so, i.e. if the last light emitting diode 12 of the downstream road element 10 is not illuminated. If it is illuminated, an inhibit signal is passed to the logic element 13 of the upstream road element 10 along line 15.

Road elements in the form of junctions will have light emitting diodes arranged in T-shaped or X-shaped configuration according to the type of junction represented. Road elements in the form of signal controlled junctions include means whereby an operator can adjust the phasing of the control signals (traffic lights) and also possibly the turn ratios, i.e. the percentage of traffic turning to the left and/or the right. This will allow an operator to simulate traffic flow accurately and tune the control signals to obtain optimum flow.

The rate at which traffic enters the simulated road network at any point is governed by a manually adjustable variable frequency pulse generator (not shown).

It is thus possible for any single person or group of persons to build a model of an existing or proposed road network and to tune the control signals by trial and error in order to optimise traffic flow along the network.

Each "vehicle" station on a road element could be represented by two or more light emitting diodes of different colours. The logic element 13 could then be arranged to illuminate a light emitting diode of appropriate colour to provide a visual indication of the environmental impact of the traffic at any given time. For example, each "vehicle" station could be represented by green, yellow and red light emitting diodes. In this case, the green diode could be illuminated when the "vehicle" is travelling quickly to represent low pollution, the yellow diode could be illuminated when the "vehicle" is travelling slowly and the red diode could be illuminated when the "vehicle" is at standstill to represent high pollution.

In another embodiment, the simulated road network described with reference to Figure 1 is controlled by an intelligent controller, such as a computer. In this case, the rate at which "vehicles" enter the network at any point can be controlled according to information programmed into the controller. Also the turn ratios at junctions and the phasing of control signals (traffic lights) can also be controlled according to information programmed into the controller. The intelligent controller may then vary the phasing of the control signals to optimise traffic flow at any particular time.

However, the intelligent controller needs to know the physical layout of the road elements 10 and rather than feed this information into the controller it is preferable for the controller to be able to ascertain the layout for itself and configure itself accordingly.

In order that the intelligent controller may do this, each road element 10 is also provided with a command highway 16 as shown in Figure 2. The command highway includes a solid state switch 17, which interrupts the electrical connection of the highway 16 to a subsequent road element 10, and a programmable logic element 18 which interfaces with the logic element 13 of the data highway 11. Each logic element 18 may have its own unique identity for identification and subsequent addressing, but preferably each element 18 has a type identity indicative of the type of the road element, e.g. a priority road junction or a signal controlled road junction, and in this case, the intelligent controller is programmed to assign a unique identity to each logic element in the following manner.

In the start up state, the switch 17 of each road element 10 is open causing each road element in turn to "look" to the intelligent controller as if it is the last road element in the physical layout. When the controller is instructed to interrogate the physical model the following procedure is followed:i. The controller issues a special 'what are you' command to which the logic element 18 of the first road element 10 responds with information about what type of element it is and its current physical settings.

ii. The controller processes the received data, assigns an ID to the logic element 18 and incorporates the element position, description and characteristics into its internal software model.

iii. The controller now causes the logic element 18 to store its newly assigned ID and addresses it to ensure it is responding correctly.

iv. The controller issues an 'OK' command to the logic element 18 just identified and this causes it to close the interrupt switch 17 and complete the highway connection through to the next road element 10. The logic element 18 of the first road element will now ignore any subsequent 'what are you' commands and will illuminate an LED 19 to provide visual confirmation of successful incorporation into the software model.

v. Any junction road elements will contain command highway interrupt switches for each 'leg' of the junction.

When a leg has been followed to its termination ( e.g. a pulse generator) the controller will return to the junction element and command the interrupt switch for the next leg to close. It will then follow that leg to its termination.

vi. This sequence is repeated until all elements in the physical model are mapped into the software model and conventional steady state control may be exerted.

In its active state, the command highway 15 allows for the addressing of any road element 10 and the subsequent passing of data, in either direction, between the road element and the intelligent controller. This can be achieved by the use of addressing and messaging techniques similar to the current Ethernet and X.25 protocols.

This method of identifying the location of randomly connected components and then controlling them may have other applications. For example, it could be used to identify the location of, and then control, power to components of a hi-fi stacking system or electrical components of a road vehicle.

Also, the apparatus described above for modelling the flow of road traffic could be used instead to model the flow of pedestrian traffic or to model the flow of other objects, such as objects moving along conveyors in a factory.

Claims (14)

1. Apparatus for modelling the flow of moving objects, comprising a plurality of component parts which can be connected together to represent a network along which the objects pass, at least some of the component parts representing obstacles to be encountered by the objects as they pass along the network, each component part having a plurality of light emitting devices and control means for energising the light emitting devices to simulate the movement of objects along the component part, the control means being responsive to a signal indicative of an obstacle encountered by the objects in its own component part or in a part immediately downstream thereof to retard or arrest the simulated movement of objects along its own component part, and means for controlling the rate at which simulated objects enter the network.

2. Apparatus as claimed in claim 1, wherein the means for controlling the rate at which simulated objects enter the network is a manually adjustable variable frequency pulse generator.

3. Apparatus as claimed in claim 1, wherein the means for controlling the rate at which simulated objects enter the network is an intelligent controller which varies the rate at which simulated objects enter the network according to information programmed into the controller.

4. Apparatus as claimed in any one of claims 1 to 3, wherein the apparatus is for modelling the flow of vehicular traffic along a road network and wherein some of the component parts represent road junctions and/or roundabouts.

5. Apparatus as claimed in claim 4, wherein some of the component parts represent junctions and/or roundabouts controlled by traffic lights and wherein these component parts are provided with means for tuning the traffic lights so as to optimise the traffic flow along the network.

6. Apparatus as claimed in claim 5 when dependent upon claim 3, wherein the traffic lights are tuned by the intelligent controller.

7. Apparatus as claimed in any one of the preceding claims and including an intelligent controller which is able to ascertain for itself the physical layout of the component parts and configure itself accordingly.

8. Apparatus as claimed in claim 7, wherein each of the component parts has a programmable logic element which can be interrogated by the intelligent controller and a solid state switch which is, in use, closed by the logic element in response to a command issued by the intelligent controller after the intelligent controller has interrogated the programmable logic element to connect the intelligent controller to the next component part in the network.

9. Apparatus as claimed in claim 8, wherein each logic element has its own unique identity.

10. Apparatus as claimed in claim 8, wherein each logic element has a type identity indicative of the type of the component part and wherein the intelligent controller can assign a unique identity to the logic element so that the logic element can be addressed subsequently by the intelligent controller.

11. Apparatus for modelling the flow of moving objects, substantially as hereinbefore described with reference to the accompanying drawings.

12. Apparatus for electronically identifying the location of randomly connected components of a network, comprising an intelligent controller, a programmable logic element, which can be interrogated by the intelligent controller, in each of the components and a solid state switch which is, in use, closed by the logic element in response to a command issued by the intelligent controller after the intelligent controller has interrogated the programable logic element to connect the intelligent controller to the next component of the network.

13. Apparatus as claimed in claim 12, wherein each logic element has its own unique identity.

14. Apparatus as claimed in claim 12, wherein each logic element has a type identity indicative of the type of the component and wherein the intelligent controller can assign a unique identity to the logic element so that the logic element can be addressed subsequently by the intelligent controller.