GB2594540A

GB2594540A - Traffic signalling apparatus

Info

Publication number: GB2594540A
Application number: GB2018132.7A
Authority: GB
Inventors: Nelson Douglas; Michael Hutchinson Peter
Original assignee: AGD Systems Ltd
Current assignee: AGD Systems Ltd
Priority date: 2019-11-21
Filing date: 2020-11-18
Publication date: 2021-11-03
Anticipated expiration: 2040-11-18
Also published as: GB201916993D0; GB2594540B; GB202018132D0

Abstract

A traffic signalling apparatus 100 comprising a signal head 106 including at least one variable-intensity light 110 (e.g. a red, amber or green light); a sensing system 112 configured to detect a range and speed of an approaching vehicle; and a controller 118 configured to vary an intensity level of the light in response to a predetermined characteristic detected by the sensing system. The speed sensor may be a radar device such as FMCW radar. The apparatus may include an ambient light sensor 116 and the controller may further modify the intensity level in response to a detected increased or decreased ambient light level. The intensity level may vary between discrete levels (e.g. a full, a reduced and a further reduced intensity level) or may vary continuously or incrementally between a maximum and minimum level. The traffic signalling apparatus may be portable, i.e. movable to a location for temporary use.

Description

TRAFFIC SIGNALLING APPARATUS

The present invention relates to a traffic signalling apparatus, and more specifically but not necessarily exclusively to a portable traffic signalling apparatus. The invention also relates to a method of operating a traffic signalling apparatus.

It is commonplace to control the flow of traffic over a junction, crossing, or other part of a carriageway by the use of traffic signals. These signals provide information to drivers and/or pedestrians in order to let them know whether it is safe or legal for them to use a particular stretch of road. Whilst traffic signals are used extensively in fixed positions, it is also desirable to use portable traffic signals in places where fixed signals are not normally used, such as during road maintenance works, or where the fixed signals have failed.

For both fixed traffic signals and temporary or portable traffic signals, it is desirable to reduce the power consumption of the signals. In the case of portable traffic signals, the reduction of power consumption can allow the traffic signals to operate for a longer period of time without recharging or battery replacement, or can allow smaller batteries or other alternative power sources to be used. In the case of fixed traffic signals, decreased power consumption may be desirable in an effort to decrease power consumption to reduce carbon emissions and/or to reduce the costs of operation.

According to a first aspect, there is provided a traffic signalling apparatus, comprising; a signal head including at least one variable-intensity light; a sensing system configured to detect a range and a speed of a vehicle approaching the traffic signalling apparatus; and a controller configured to vary an intensity level of the at least one variable-intensity light in response to a predetermined characteristic detected by the sensing 30 system.

By varying the intensity level of the light emitted from the signal head, power consumption of the apparatus can be reduced. As the sensing system can detect both a range and speed of any approaching vehicles, the controller can vary the intensity as necessary to provide safe signalling to any approaching vehicles in good time for them to stop, for example, whilst ensuring that energy is not wasted by illuminating the at least one variable-intensity light at a time when it is not visible to an approaching vehicle.

Of course, the variable-intensity lights may be turned off at points during any light cycle, or may flash. Therefore, where references are made to the intensity level of the variable-intensity light, it is intended to be a reference to the intensity of the lights at a time when they are lit.

In order that the traffic signalling apparatus has visible lights when in operation, the intensity level may be selected such that it is always non-zero. Again, such a non-zero intensity level is not intended to refer to when a light is switched off during a cycle, e.g. if, during a cycle a red light is lit and a green light is not lit, the intensity level of the green light can still be considered to be non-zero as this will be the case when it is lit.

The controller may be configured to operate the at least one variable-intensity light at a higher intensity level when the predetermined characteristic is fulfilled and at a lower intensity level when the predetermined characteristic is not fulfilled.

The predetermined characteristic may include a predetermined range and a predetermined speed, or a combination of a speed and range of an approaching vehicle.

The predetermined range may be, for example, between 2 and 100 metres, between 2 and 50 metres, between 2 and 20 metres, between 50 and 100 metres, between 20 and 100 metres, and/or between 20 and 50 metres. The predetermined range may be or may substantially be 2 metres, 20 metres, 50 metres, or 100 metres.

The predetermined speed may be, for example, between 2 and 60 mph, between 2 and 30 mph, and/or between 30 and 60 mph. The predetermined speed may be or may be substantially be 2 mph. 30 mph, or 100 mph.

For example, the range that causes the higher intensity level to be applied may change depending on the speed of the approaching vehicle. It can therefore be ensured that the traffic signalling apparatus is illuminated to a sufficient extent to give adequate warning to any approaching vehicle.

The sensing system may include a radar device configured to detect the range and the speed of a vehicle approaching the traffic signalling apparatus. The radar device may include a frequency-modulated continuous-wave (FMCW) radar.

The sensing system may include an ambient light sensor, the controller being further configured to modify the intensity level of the at least one variable-intensity light in response to an ambient light level detected by the ambient light sensor.

The controller may be configured to modify the intensity level of the at least one variable-intensity light to be higher in response to a detected increased ambient light level and lower in response to a detected decreased ambient light level.

The ambient light sensor may therefore cause the traffic signalling apparatus to operate in a "light mode" and a "dim mode", i.e when the ambient light level is above a certain level the lights will operate at a high intensity level and when the ambient light level is below a certain level the lights will operate at a low intensity level. In each case, the fulfilment of the predetermined criteria will then cause the adjustment of the intensity level further, but the intensity levels during the "light mode" will be when the predetermined characteristic is fulfilled and when the predetermined characteristic is not fulfilled will be higher than the intensity levels during the "dim mode".

The use of an ambient light sensor allows the brightness of the light to be adjusted for the ambient light conditions. For example, the intensity of the light does not need to be as high during the night as it is during the day to have a similar level of visibility to approaching drivers. Therefore by dimming the light during low ambient light conditions, power consumption can be further reduced.

The intensity level may be configured to vary between a plurality of discrete intensity levels. The plurality of discrete intensity levels may include at least three discrete intensity levels. The plurality of discrete intensity levels may include a full intensity level, a reduced intensity level, and a further reduced intensity level.

The controller may be configured to vary the intensity level of the at least one variable-intensity light: to the full intensity level during high ambient-light operation when the predetermined characteristic is fulfilled; to the reduced intensity level during high ambient light operation when the predetermined characteristic is not fulfilled; to the reduced intensity level during low ambient-light operation when the predetermined characteristic is fulfilled: and to the further reduced intensity level during low ambient-light operation when the predetermined characteristic is not fulfilled The intensity level may be configured to vary continuously or substantially continuously between a minimum intensity level and a maximum intensity level.

By substantially continuously, it is meant that the intensity level may be varied in small, discrete intervals. For example, this would be the case where digital control of the intensity is provided.

The controller may be configured to vary the intensity level of the at least one variable-intensity light to be at the maximum intensity level during high ambient-light operation when the predetermined characteristic is fulfilled and to be at the minimum intensity level during low ambient-light operation when the predetermined characteristic is not fulfilled.

The controller may be configured to change the intensity level of the at least one variable-intensity light incrementally from one intensity level to another intensity level.

By varying the change of intensity level incrementally, any sudden change in intensity that could be otherwise surprising or shocking to an oncoming vehicle can be avoided.

The incremental change of intensity level may be provided over a predetermined number of cycles of the lights. For example, if three lights are used in a standard traffic light formation, a change in intensity level may occur incrementally over one, two, three, or more cycles of the red-red/amber-green-amber-red pattern.

The at least one variable-intensity light may include a red light and a green light.

The at least one variable-intensity light may include an amber light.

The traffic signalling apparatus may be a portable traffic signalling apparatus configured to be movable to a location for temporary use.

The portable traffic signalling apparatus may include one or more of the following features: - a portable power source such as a battery, generator, solar panelwind turbine, or other power source; - wheels; and - a tow bar or other device by which the portable traffic signalling apparatus may be propelled.

According to a second aspect, there is provided a method of operating a traffic signalling apparatus comprising a signal head including at least one variable-intensity light, and a sensing system configured to detect a range and a speed of a vehicle approaching the traffic signalling apparatus, the method comprising: varying the intensity level of the at least one variable-intensity light in response to a predetermined characteristic detected by the sensing system, by operation of a controller.

The method may further comprise the steps of operating the at least one variable-intensity light at a high intensity level when the predetermined characteristic is fulfilled and at a low intensity level when the predetermined characteristic is not fulfilled.

The method may further comprise the step of modifying the intensity level of the at least one variable-intensity light in response to an ambient light level detected by an ambient light sensor.

The intensity level may be varied between a plurality of discrete Intensity levels, optionally at least three discrete intensity levels, which may include a full intensity level, a reduced intensity level, and a further reduced intensity level.

The intensity level may be varied continuously or substantially-continuously between a minimum intensity level and a maximum intensity level.

The intensity level may be varied to be at the maximum intensity level during high ambient-light operation when the predetermined characteristic is fulfilled and varied to be at the minimum intensity level during low ambient-light operation when the predetermined characteristic is not fulfilled The method may further comprise incrementally changing the intensity level of the at least one variable-intensity light from one intensity level to another intensity level.

The incremental change may be provided over a predetermined number of cycles of the lights.

Specific embodiments will now be described in detail with reference to the accompanying drawings, in which: Figure 1 is a simplified depiction of a traffic signalling apparatus in accordance with the first aspect; Figure 2 is a schematic diagram of the controller, sensing system, and variable-intensity lights of Figure 1; and Figure 3 is a flow chart of the method according to the second aspect.

Referring firstly to Figures 1 and 2, there is shown a traffic signalling apparatus 100.

The traffic signalling apparatus 100 includes a base 102, a pole 104 extending vertically from the base 102, and a signal head 106 supported by the pole 104. The base 102 is mounted upon two wheels 108, enabling the traffic signalling apparatus 100 to be portable and easily moved between locations.

The signal head 106 includes three variable-intensity lights 110, hereafter referred to simple as "lights". In other embodiments, a greater or lesser number of lights 110 may be provided. The lights 100 are coloured in common with well-known traffic signalling apparatuses such that the upper light is red, the lower light is green, and the middle light is amber.

On top of the signal head 106 is mounted a sensing system 112. The sensing system 112 of the depicted embodiment includes a frequency-modulated continuous-wave (FMCW) radar device 114, which operates in order to provide both range and speed readings related to vehicles approaching the traffic signalling apparatus 100. An ambient light sensor 116 is also provided in the sensing system 112, which senses ambient light in the vicinity of the traffic signalling apparatus 100.

The sensing system 112 and signal head 106 are each controlled by a controller 118, which in the present embodiment is housed within the base 102. A battery 120 is also provided in the base 102 in order to provide power to the traffic signalling system 100. Whilst a battery 120 is provided in the present traffic signalling apparatus 100, other suitable power supplies may also be provided, of which the possibilities will be known to the skilled person.

Illumination of each of the lights 110 is possible in a range of intensity levels, dictated by the controller 118. The controller 118 therefore receives sensing data from the sensing system 112 and uses this data to control the intensity level of the lights 110.

The FMCW radar device 114 is configured to detect range and speed data of vehicles approaching the traffic signalling apparatus 100 and to provide this data to the controller 118. Ambient light data is also provided to the controller 118 by the ambient light sensor 116. The controller 118 utilises the range and speed data and the ambient light data and checks this data against a predetermined characteristic. The predetermined characteristic is used to determine the intensity level at which the lights 110 should be operated in response to the data received from the sensing system 112.

It is therefore possible for the traffic signalling apparatus 100 to respond dynamically to the presence or absence of vehicles approaching the traffic signalling apparatus 100.

In the present embodiment, the predetermined characteristic is that a vehicle is detected within a predetermined range of the traffic signalling apparatus 100 and that it is travelling at a speed to arrive at the traffic signalling apparatus 100 within a predetermined time. In response to the predetermined characteristic being fulfilled, the intensity level of the lights 110 is set such that the lights 110 are sufficiently visible to approaching vehicles. However, when the predetermined characteristic is not fulfilled, i.e. when a vehicle is not within the predetermined range of the traffic signalling apparatus 100 and/or not travelling at a speed to arrive at the traffic signalling apparatus 100 within the predetermined time, the controller 118 can lower the intensity level of the lights 110 such that the power consumption of the traffic signalling apparatus 100 is lower than it otherwise would he.

The ambient light data is used by the controller 118 to further modify the intensity level of the lights 110. When the ambient light level is high, such as during bright sunshine, the intensity level of the lights 110 is increased to ensure good visibility of the lights 110. Conversely, when the ambient light level is lower, such as during cloudy weather or at night, the intensity level of the lights 110 is decreased to ensure that energy use is decreased when it is not necessary to provide higher intensity light, whilst ensuring that the lights 110 are visible to oncoming traffic when required.

In operation, as shown in Figure 3, the controller 118 receives data Si from the sensing system 112 and checks this information against the predetermined characteristic S2. The intensity level is then checked S3 and varied S4 as necessary. Ambient light data is then used to adjust the intensity level S5, in order to avoid excess power usage.

As will he apparent to the skilled person, the predetermined characteristic may he chosen by the operator of the system in order to ensure safe operation of the traffic signalling apparatus 100. For example, the detection range of the radar device 114 may be increased where it is necessary to adapt the intensity level of the lights 110 further in advance, such as when a vehicle is likely to be travelling at high speed. The range and speed parts of predetermined characteristic may also be controlled such that it is a combination of the range and speed of approaching vehicles that is taken into account when varying the intensity level of the lights 110. For example, a vehicle travelling at the same range but a higher speed than another vehicle may result in earlier adaption of the intensity level of the lights 110.

In one method of operation, it may be desirable to operate the traffic signalling apparatus 100 with a total of three intensity levels: a full brightness intensity level, a reduced intensity level, and a further reduced intensity level. The intensity levels may he selected by the controller 118 on the basis of the below table: High ambient light Low ambient light level level Vehicle approaching present / Full brightness Reduced intensity level intensity level No vehicles Reduced intensity level Further reduced intensity level The further reduced intensity level may be, for example, 20 percent less bright than the reduced intensity level. The reduced intensity level may he, for example, 50 percent less bright than the full brightness intensity level. However, the relative brightness of the intensity levels may be chosen to fit the specific intended operating conditions of the traffic signalling apparatus 100.

The full brightness intensity level is equivalent to the normal brightness level of a known traffic signalling system. As such, whenever the intensity level is reduced, power consumption can be lowered. This is enabled due to the traffic signalling system being configured such that lower intensity levels have a lower power consumption than higher intensity levels. This may he provided by the configuration of the controller or other circuitry within the system and specific methods of implementation will be known to the skilled person.

The change in intensity levels will generally be a step-change, i.e. the change will be instantaneous between one intensity level and another. However, in some methods of operation, it may be desirable to change the intensity levels over a period of time, for example in order to prevent a surprising change in brightness. The intensity change may therefore be incrementally changed between one intensity level and another intensity level, either over a predetermined period of time or over a predetermined number of cycles of the lights 110. It will be well-known to the skilled person that traffic signals often operate in cycles, e.g. red-red/amber-green-amber-red. Therefore, changes in intensity may he provided over the course of a single cycle or over a predetermined number of cycles of the traffic signals.

In some methods of operation, it may he desirable to transition the intensity levels of the lights in one direction as a step-change and in the other direction as an incremental change. For example, when increasing intensity level when a vehicle is detected, it may be desirable to instantly increase the intensity level in order to provide the greatest possible warning to the driver of the vehicle. Conversely, when decreasing intensity level, it may he desirable to incrementally decrease the brightness over a number of cycles.

Incremental decreases or increases in brightness may he particularly useful during modification of the intensity level in view of the ambient light level. The intensity may therefore be modified slowly as light levels decrease and increase over their natural cycles.

Claims

CLAIMS1. A traffic signalling apparatus, comprising; a signal head including at least one variable-intensity light; a sensing system configured to detect a range and a speed of a vehicle approaching the traffic signalling apparatus; and a controller configured to vary an intensity level of the at least one variable-intensity light in response to a predetermined characteristic detected by the sensing System.
2. A traffic signalling apparatus according to claim 1, wherein the controller is configured to operate the at least one variable-intensity light at a higher intensity level when the predetermined characteristic is fulfilled and at a lower intensity level when the predetermined characteristic is not fulfilled.
3. A traffic signalling apparatus according to claim 1 or claim 2, wherein the predetermined characteristic includes a predetermined range of an approaching vehicle and a predetermined speed of an approaching vehicle, or a combination of a speed and range of an approaching vehicle.
4. A traffic signalling apparatus according to any preceding claim, wherein the sensing system includes a radar device configured to detect the range and the speed of a vehicle approaching the traffic signalling apparatus, optionally wherein the radar device includes an FMCW radar.
5. A traffic signalling apparatus according to any preceding claim, wherein the sensing system includes an ambient light sensor, the controller being further configured to modify the intensity level of the at least one variable-intensity light in response to an ambient light level detected by the ambient light sensor.
6. A traffic signalling apparatus according to claim 5, wherein the controller is configured to modify the intensity level of the at least one variable-intensity light to be higher in response to a detected increased ambient light level and lower in response to a detected decreased ambient light level.
20 25 30 7. A traffic signalling apparatus according to any preceding claim, wherein the intensity level may be configured to vary between a plurality of discrete intensity levels.
8. A traffic signalling apparatus according to claim 7, wherein the plurality of discrete intensity levels includes at least three discrete intensity levels.
9. A traffic signalling apparatus according to claim 8, wherein the plurality of discrete intensity levels include a full intensity level, a reduced intensity level, and a further reduced intensity level.
10. A traffic signalling apparatus according to claim 9, wherein the controller is configured to vary the intensity level of the at least one variable-intensity light: to the full intensity level during high ambient-light operation when the predetermined characteristic is fulfilled; to the reduced intensity level during high ambient light operation when the predetermined characteristic is not fulfilled; to the reduced intensity level during low ambient-light operation when the predetermined characteristic is fulfilled; and to the further reduced intensity level during low ambient-light operation when the predetermined characteristic is not fulfilled.
11. A traffic signalling apparatus according to any of claims 1 to 6, wherein the intensity level is configured to vary continuously or substantially continuously between a minimum intensity level and a maximum intensity level.
12 A traffic signalling apparatus according to claim 11, wherein the controller is configured to vary the intensity level of the at least one variable-intensity light to be at the maximum intensity level during high ambient-light operation when the predetermined characteristic is fulfilled and to be at the minimum intensity level during low ambient-light operation when the predetermined characteristic is not fulfilled.
13. A traffic signalling apparatus according to any preceding claim, wherein the controller is configured to change the intensity level of the at least one variable-intensity light incrementally from one intensity level to another intensity level.
14. A traffic signalling apparatus according to claim 13, wherein the incremental change of intensity level is provided over a predetermined number of cycles of the lights.
15. A traffic signalling apparatus according any preceding claim, wherein the at least one variable-intensity light includes a red light and a green light.
16. A traffic signalling apparatus according to any preceding claim, wherein the at least one variable-intensity light includes an amber light.
17. A traffic signalling apparatus according to any preceding claim, wherein the traffic signalling apparatus is a portable traffic signalling apparatus configured to be movable to a location for temporary use.
18. A method of operating a traffic signalling apparatus comprising a signal head including at least one variable-intensity light, and a sensing system configured to detect a range and a speed of a vehicle approaching the traffic signalling apparatus, the method comprising: varying the intensity level of the at least one variable-intensity light in response to a predetermined characteristic detected by the sensing system, by operation of a controller.
19. A method according to claim 18, further comprising the steps of operating the at least one variable-intensity light at a high intensity level when the predetermined characteristic is fulfilled and at a low intensity level when the predetermined characteristic is not fulfilled.
20. A method according to claim 18 or claim 19, further comprising the step of modifying the intensity level of the at least one variable-intensity light in response to an ambient light level detected by an ambient light sensor.
21. A method according to any of claims 18 to 20, wherein the intensity level is varied between a plurality of discrete intensity levels, optionally at least three discrete intensity levels, which may include a full intensity level, a reduced intensity level, and a further reduced intensity level.
22. A method according to any of claims 18 to 20, wherein the intensity level is varied continuously or substantially continuously between a minimum intensity level and a maximum intensity level.
23. A method according to claim 22, wherein the intensity level is varied to he at the maximum intensity level during high ambient-light operation when the predetermined characteristic is fulfilled and varied to be at the minimum intensity level during low ambient-light operation when the predetermined characteristic is not fulfilled.
24. A method according to any of claims 18 to 21, further comprising incrementally changing the intensity level of the at least one variable-intensity light from one intensity level to another intensity level, optionally providing the incremental change over a predetermined number of cycles of the lights.
25. A method according to any of claims 18 to 24, wherein the traffic signallii apparatus is a portable traffic signalling apparatus configured to be movable to a location for temporary use.