WO2025209941A1

WO2025209941A1 - A real time driver warning system

Info

Publication number: WO2025209941A1
Application number: PCT/EP2025/058571
Authority: WO
Inventors: John MOYNIHAN; Tony MAGUIRE; Sean LOUGHLIN; Dominic Southgate; Neil Murray; Scott Bennett
Original assignee: Lagan Crawl Ltd
Current assignee: Lagan Crawl Ltd
Priority date: 2024-04-02
Filing date: 2025-03-28
Publication date: 2025-10-09
Anticipated expiration: 2026-10-02

Abstract

A driver warning system has roadside controllers (150) arranged to be mounted near a road, and short interval warning devices (1) each with a saddle shape to be mounted to a central reservation barrier with a wing on each lateral side and a controller housing on top, and each wing has at least one LED array. Control processors (152, 11) and interfaces allow the roadside controllers and the devices to communicate with each other, and the roadside controller transmits commands to devices to cause coordinated activation of the LED arrays to issue warning information to drivers. Devices (1) can relay control messages to a next successive device in a message hopping scheme and roadside controllers can identify a break in a message relay chain and generate an alert identifying that a device is faulty accordingly. Each device (1) is modular so that in the unlikely event of an impact only a small portion may break off and this is very likely due to the low-profile construction and use of captive screw fixings.

Description

“A Real Time Driver Warning System”

Introduction

The present invention relates to provision of real time driver warnings by way of roadside warning devices.

It is known to provide such a system as described in our published PCT specification number W02022/136010. This describes a system with a series of short interval warning devices which are saddle-shaped with lower LED display components which in use are at approximately the driver’s eye level. These units are best mounted with a separation in the range of 50 m to 500 m apart. The display components are visible by drivers on both sides of a dual carriageway (but only on the side of the road the driver is driving on), thereby providing bi-directional use. In the disclosure, at least some lower display components each comprises light sources mounted on a base plate, and the light sources may comprise an array of LEDs.

The present invention is directed towards providing improvements and/or additional advantageous features of such short interval warning devices and systems incorporating them.

Summary of the Invention

We describe a driver warning system comprising: a plurality of roadside controllers arranged to be mounted near a road, and a plurality of short interval warning devices each configured with a saddle shape to be mounted to a central reservation barrier with a wing on each lateral side of the barrier and of a longitudinal direction, and each wing has at least one lamp, and a top housing containing a controller, wherein the roadside controllers and the short interval warning devices each has a control processor and an interface to communicate with each other, and the roadside controller processor is configured to transmit commands to a plurality of short interval devices to cause coordinated activation of the lamps to issue warning information to drivers.

In some preferred examples, at least some devices each comprise a mesh controller and an antenna to relay control messages to a next successive device in a message hopping scheme.

In some preferred examples, at least some roadside controllers are configured to identify a break in a message relay chain and to generate an alert identifying that a device is faulty accordingly. In some preferred examples, the controller of at least some short interval warning devices is configured to activate an lamp on a side opposed to the side of an accident to assist emergency vehicles to identify a scene of an incident.

In some preferred examples, at least some short interval warning devices are each configured to be assembled off-site and secured as a single unit to a barrier.

In some preferred examples, each short interval warning device is configured to be secured to a barrier by captive fixings, preventing a fixings from falling on a roadway.

In some preferred examples, each short interval warning device comprises a saddle-shaped base with a top plate and wing plates of metal.

In some preferred examples, each short interval warning device lamp comprises an LED array mounted to a laterally extending support. In some preferred examples, each wing has two lamps, one facing towards each longitudinal direction.

In some preferred examples, each wing has said laterally extending support and an LED array mounted to a longitudinally facing surface.

In some preferred examples, at least one lamp comprises an LED array which is in a plane extending at an angle to normal to longitudinal, and said angle is in the range of 1° to 7°, preferably 3° to 5°.

In some preferred examples, each wing has a laterally extending support and an LED array mounted to a longitudinally facing surface, and said surfaces extend at said angle to normal to longitudinal.

In some preferred examples, each short interval warning device laterally extending support is on a lamp base which is in turn secured to a wing plate adapted to be secured to a barrier.

In some preferred examples, each lamp comprises a housing surrounding an LED array and said housing is secured to a wing plate. In some preferred examples, each housing comprises a detachable transparent portion secured to a primary housing part via a gasket.

In some preferred examples, each device controller is configured to confirm if a requested action has been successfully executed or if there is an error in executing the command.

In some preferred examples, each device control processor is configured to perform control of light parameters including one or more of brightness, flash rate, synchronised flashing, unsynchronised flashing, and/or alternate colours.

In some preferred examples, at least some of the roadside controllers are configured to log and timestamp events to provide an audit log of traffic conditions and/or individual vehicle information, for retrieval should an accident occur.

In some preferred examples, at least one of said roadside controllers and/or short interval warning devices comprises radar units to detect vehicle speed and to generate warning LED activations accordingly.

In some preferred examples, at least one roadside controller and/or some devices comprise illumination projection devices to project images onto a road surface, such as images to indicate that a lane is not to be used.

In some preferred examples, the device further comprises a physical cable link between at least some roadside controllers and a short interval warning device for transmission of power and control signals.

In some preferred examples, a plurality of the short interval warning devices are linked in a multidrop physical cable link running along a top surface of a road reservation barrier.

In some preferred examples, each roadside controller is linked by said cable link to a single short interval warning device, and said device is configured to route power and control instructions to a series of a plurality of short interval warning devices by said cable secured to the barrier.

In some preferred examples, the short interval warning device controllers comprise mesh controllers configured to communicate with a plurality of other devices via both wired and cable links to ensure alternative paths are available, and to signal to a roadside controller if a device is not responding.

In some preferred examples, the roadside controller and the short interval warning device controllers are configured to communicate warning lamp control signals with structured messages, each having a header, a payload, and a footer, the payload having lamp control parameters including one or more selected from brightness, flashing frequency, and colour.

In some preferred examples, a subset of the short interval warning devices comprises a sign, and the roadside controller comprises an associated sign, and the roadside controller is configured to transmit sign control messages to short interval warning devices comprising signs.

We also describe a short interval warning device configured with a saddle shape to be mounted to a central reservation barrier, the device comprising: a wing on each lateral side of a longitudinal direction, each wing comprising at least one lamp, and a top housing containing circuit boards with processors providing a controller and an interface, wherein said interface is configured to communicate with other short interval warning devices for coordinated activation of the lamps to issue warning information to drivers.

Various other features are set out in appended claims 28 to 42.

We also describe a driver warning system comprising: a plurality of roadside controllers arranged to be mounted near a road, and a plurality of short interval warning devices each configured with a saddle shape to be mounted to a central reservation barrier with a wing on each lateral side and a controller in a top housing, and each wing has at least one lamp, wherein the controllers and the devices each have a control processor and an interface to communicate with each other, and the roadside controller processor is configured to transmit commands to a plurality of devices to cause coordinated activation of the LED arrays to issue warning information to drivers.

In some preferred examples, at least some devices are configured to relay control messages to a next successive device in a message hopping scheme. In some preferred examples, at least some roadside controllers are configured to identify a break in a message relay chain and to generate an alert identifying that a device is faulty accordingly.

In some preferred examples, the controller of at least some devices is configured to activate an LED array on a side opposed to the side of an accident to assist emergency vehicles to identify a scene of an incident. In some preferred examples, at least some devices are each configured to be assembled off-site and secured as a single unit to a barrier.

In some preferred examples, each device is configured to be secured to a barrier by captive fixings, preventing a fixing from falling on a roadway during servicing. In some preferred examples, each device comprises a saddle-shaped base with a top plate and wing plates, preferably of metal.

In some preferred examples, each device lamp comprises an LED array mounted to a laterally extending support. In some preferred examples, each wing has two lamps, one facing each longitudinal direction.

In some preferred examples, each wing has said laterally extending support and an LED array mounted to each longitudinally facing surface.

In some preferred examples, each device laterally extending support is on a lamp base which is in turn secured to a wing plate. In some preferred examples, each lamp comprises a housing surrounding light sources and said housing is secured to a wing plate.

In some preferred examples, each housing comprises a detachable transparent portion secured to a primary housing part via a gasket. In some preferred examples, each device controller is configured to confirm if a requested action has been successfully executed or if there is an error in executing the command.

In some preferred examples, each device control processor is configured to perform control of light parameters including brightness, flash rate, synchronised flashing, unsynchronised flashing, and/or alternate colours.

In some preferred examples, at least some of the roadside controllers are configured to log and timestamp events to provide an audit log of traffic conditions and/or individual vehicle speeds should an accident occur. In some preferred examples, at least one of said roadside controllers and/or devices comprises radar units to detect vehicle speed and to generate warning LED activations accordingly.

In some preferred examples, roadside controllers and/or devices comprise illumination projection devices to project images onto road lanes, such as images to indicate that a lane is not to be used.

We also describe a driver warning system short interval warning device configured with a saddle shape to be mounted to a central reservation barrier with a wing on each lateral side and a controller in a top housing, and each wing has at least one lamp.

In some preferred examples, at least some devices are configured to be assembled off-site and secured as a single unit to a barrier.

In some preferred examples, the device is configured to be secured to a barrier by captive fixings, preventing a fixing from falling on a roadway during servicing.

In some preferred examples, the device comprises a saddle-shaped base with a top plate and wing plates, preferably of metal.

In some preferred examples, each device lamp comprises an LED array mounted to a laterally extending support.

In some preferred examples, each wing has two lamps, one facing in each longitudinal direction. In some preferred examples, each wing has said laterally extending support and an LED array mounted to each longitudinally facing surface. In some preferred examples, each device said laterally extending support is on a lamp base which is in turn secured to a wing plate.

In some preferred examples, each lamp comprises a housing surrounding light sources and said housing is secured to a wing plate. In some preferred examples, each housing comprises a detachable transparent portion secured to a primary housing part via a gasket.

Detailed Description of the Invention

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings in which: Fig. 1 is a perspective view of a real time road traffic warning system as it is installed a short length of dual carriageway,

Fig. 2 is a perspective view of a short interval warning device for signalling warning to drivers at eye level on a barrier, and Fig. 3 is an exploded view of the device,

Fig. 4 is a perspective view of the device of Figs. 2 and 3 installed on a barrier and with solar panels attached,

Fig. 5 is a perspective view of a rotating sign short interval warning device in place on a barrier,

Fig. 6 is a block diagram of the functionality of the device of Figs. 2 and 3,

Fig. 7 is a block diagram showing interconnection of the short interval warning devices along a 400 m stretch of roadway, and

Fig. 8 is a block diagram showing a roadside cabinet functionality.

Detailed Description of the Embodiments

Referring to Fig. 1, a driver warning system of the invention has multiple short interval warning devices 1, less frequent short interval warning devices 100 with rotatable display screens, and a smaller number of roadside controllers 150. Each roadside controller 150 is linked with multiple devices 1 and 100, depending on the range and site conditions.

As is shown in Fig. 1 the devices 1 and 100 are mounted by way of saddle-shaped structures to the to of a barrier B between the two sides of the dual-carriageway. Each has LEDs which are activated in synchronism with other devices 1 and 100 so that they provide a warning when viewed in succession together by a driver, at eye level. The roadside controllers 150 are less frequent and serve to provide signals and power to the devices 1 and 100 by way of cables under the road and the power is then then linked by cables along the top of the barrier. It is not essential that power or signalling be provided by cable from the roadside controller 150 as it can all be done wirelessly by RF. This is especially true for retrofitting a system to an existing road as it avoids the challenges of bringing cable under the road if there is no existing conduits. However, where it can be done it is advantageous to have both wired and wireless links, to provide redundancy and hence reliability, something which is very important for warning drivers in real time to prevent accidents. The roadside unts 150 also provide connectivity to remote servers and are linked to external systems such as weather forecasting systems. The roadside unit/controller 150 has a cabinet housing 162 containing most of the circuits (Fig. 8) , linked to an adjacent pole-mounted sign 163, and to a pole mounted camera 164 and in some embodiments to a radar scanner.

Referring to Figs. 2 to 4 each device 1 comprises a top part housing 10 containing various circuits as described in detail below. The top housing 10 is for location on the top of a central reservation barrier B. There is a downwardly depending wing 21 on each side of the top housing 10. The wings 21 are identical, so that the device can be used in any jurisdiction. Each wing 21 has two lamps 16, 17, on a substrate. Alternatively, there may be only one in some examples. However, a benefit of two is that each can be faced primarily in a longitudinal direction for ease of driver visibility whether the device is deployed in a right side or left side driving jurisdiction. The housing 10 contains the circuits controlling the lamps 16, 17 and performing communication with the relevant roadside controller 150 and other warning devices 1 and 100, as described in more detail below.

The main mechanical frame of the device 1 is provided by a top plate 31 to which are secured a wing plage 32 on each lateral side. A combination of the top plate 31 and the two wing plates 32 provide an integral metal frame which attaches securely to the barrier B. Each wing plate 21 indirectly supports the lamps 16 and 17, as described in more detail below. Also, the top plate 31 forms part of the top housing 10 together with a top housing cover 43. Captive fixings 34 are used throughout for securing the wing plages 32 and the top plate 31 to the barrier, providing a very strong foundation. Also, captive fixings 34 re used for securing the various components to the plates 31 and 32.

Each lamp 16, 17 comprises a rectangular LED array 37 mounted to a laterally extending (normal to the longitudinal direction and the barrier in use) plate 36, one array 37 on each longitudinal side of each plate 36. The plate 36 extends from a lamp base 35, which is in turn secured to the associated wing plate 32. The lamps 16 and 17 on each wing 21 are covered by a housing 38 which has a curved transparent cover 39 secured to the housing 38 via a gasket 40.

In preferred embodiments the plate 36 extending normal to the lamp base 35 (which itself extends in the longitudinal direction) has opposed surfaces which are tapered at an angle to normal to the base 35/32. This angle is preferably in the range of 1° to 7°, more preferably 3° to 5°. This arrangement allows each array 37 to face the driver directly, and the angle has been found to provide superior visibility than if the arrays were exactly normal to the base 35/32, being instead tilted slightly into the roadway. This taper angle may alternatively be achieved by the arrays having an in-built tilt.

Advantageously, individual components such as the housing 38 and also the plates 31 and 32 are secured by captive fixings 34, and so the fixings can not become separated and fall on the road surface either during servicing or upon an impact.

The top housing 10 houses circuit boards 45, 46, and 47, all housed within the housing top part 43. The circuit boards 45, 46, and 47 support the various device circuits, described below. The battery 44 is housed under solar panels if present.

Regarding power for the LEDs 37 and the circuits 45, 46, and 47 this is preferably provided by solar panels, one connected to each longitudinal (direction of the barrier B in use), and there is an associated battery under each solar panel 30. This allows the devices 1 to be independently powered. However as noted above a back-up can be power cabling and this is shown as reference numeral 105 in the drawings. It preferably runs along the top of the barrier B, and so is out of reach of potential impacts.

The device 1 arrangement allows universal use for central reservation barriers. Each wing 21 has a low profile, but in the unlikely event of an impact by a vehicle the housing 38 is more likely to be damaged without damage to the structure of the device 1, this structure being based primarily on the wing plates 32 and the top plate 31. The controller is very unlikely to be damaged due to its location at the top of the saddle shaped arrangement, and it has its own dedicated housing 10 made up of the top plate 31 and the top housing cover 43, and so an impact on a wing is unlikely to affect the controller. The manner in which the LED arrays 37 are mounted allows excellent visibility by oncoming drivers, as they face in the longitudinal direction.

Each device 1 is modular, as shown particularly in Fig. 3, so that in the unlikely event of an impact only a small portion may break off and this is very likely due to the low-profile construction and use of captive screw fixings.

Fig. 4 shows a device 1 after a string of two solar panels 30 have been attached at each side, and this view also shows the power and signalling cabling 105 extending along the top of the barrier B. As described in more detail below this cabling provides a robust link between the devices 1 and 100, so that there is not total reliance on RF links. This is important for reliability of driver warnings.

Fig. 5 shows one of the short interval warning devices 100 when installed on a central reservation barrier B. This has a saddle-shaped support and LED lamps 16 and 17, in an arrangement similar to the device 1. In addition, there is a display warning sign 102 mounted on a rotatable shaft for issuing readable warnings faced in a desired direction.

Referring to Fig. 6, the circuits within the top housing 10 include an LED controller 13 linked with the four LED lamps, two lamps 16, 17 on each wing. A mesh controller 11 has an antenna 12 for receiving instructions provided by the nearest roadside controller 150, and there is a solar charge controller 14 for any solar panels 30 linked with the device 1. The solar panels may be co-planar with the housing 10, for mounting to the top surface of a barrier as shown in Fig. 4. There may be one or two or more than two on each longitudinal side, as described in W02022/136010, the contents of which are incorporated herein by reference.

Referring to Fig. 7 there is a series of warning devices 1, four in total over a 400 m stretch of roadway. Equally interspersed, after every 4^th device 1, there is a short interval warning device 100 with a rotatable sign 102. This has many of the same components as the device 1 and like parts are indicated by the same reference numerals. The primary additional components are a motor 115 and a sign controller 116 to drive and control rotation of the sign 102 respectively. In addition to its role in supporting and controlling the sign 102, the device 100 also controls the warning LED lamps 16 and 17 in a synchronised manner the same as the devices 1, and also it is in this example linked to the control cabinet 150 via a physical power and control cable loom 120 under the roadway.

The cabinet 150 is shown in more detail in Fig. 8. The main controller for the cabinet is shown at 152 and this is linked by a Modbus bus to an inverter 181 which receives three-phase AC mains power from underground cables 180. The controller 152 is linked with a tamper sensor 160 which is arranged to detect tampering with the cabinet housing, and if so the controller 152 raises an alert. The main data connection is over fibre 170, however there is also a satellite backhaul wireless link interface 190 for use if needed. A separate router 166 is configured to route control signals to the camera and radar systems mounted on a pole beside the cabinet, and the outer 166 also provides a connection to the controller 152. These links also control a sign at the cabinet, with the control being performed by a controller 165. Importantly, the rotating sign control is synchronised between the cabinet’s own sign and that of the nearest warning devices 100, and these control signals are provided wirelessly and over the cable loom 120. There is a dedicated mesh microcontroller 153 for communication with the local short interval warning devices 1,100. There is also a power management circuit 167.

Each device 1, 100 can be assembled off-site and simply bolted down and connected to the road barrier, increasing speed of assembly. All fixings on the devices are captive, preventing a screw falling on the roadway during servicing.

The system is deployed so that each arbitrary road section has installed a roadside controller 150 and a number of associated short interval warning devices 1 and a smaller number of devices 100 with rotating signs 102. The devices 1 and 100 provide a configurable method of displaying warning lights (signalling action) in different patterns along the road section. Devices 1, 100 can be individually commanded by the associated roadside controller 150 either via the wireless mesh router or by the wired link 120 to take required signalling action.

Geographic location of the devices 1 and 100 may be determined during installation or automatically via individual GPS units in each device.

The type and duration of signalling action is determined at a remote operations centre which is monitoring the road remotely, and this communicates with the roadside controllers 150. However, the roadside controllers 150 can act as master controllers by default unless overridden by remote host intervention. The signalling action can be a predetermined pattern, or an arbitrary pattern as determined appropriate by the operations centre.

Each device mesh controller 11 is configured to confirm if the requested action has been successfully executed or if there is an error in executing the command. Full control of the LED lighting parameters is possible including brightness, flash rate, synchronised flashing, unsynchronised flashing, and/or alternate colours.

Communication with the individual devices 1 and 100 is either via a secure ISM wireless connection operating on licence free bands, or via the wired connection 120. In either case each device 1 can be individually addressed and commanded. Power for the devices 1 can be supplied via a number of methods including, wired, solar, battery or a combination thereof.

In the case that remote communications to the operations centre is lost by a roadside controller 150, the controller 150 may take optional autonomous action for a road section. Such action is preferably based on analysis of the local conditions on that road section as determined by local sensors or monitoring equipment such as cameras, radar, local weather sensors, temperature sensors.

The roadside controller 150 logs and timestamps events which can be used to optimise the system and also provide an audit log of traffic conditions and individual vehicle speeds should an accident occur.

Each LED controller 13 is programmed so that, in the event of an emergency, the far side LED lamps 16 and 17 could discretely flash at the accident location to assist responders approaching from the other direction, such that they would then take the next exit and double back

Each device 1 may incorporate a Bluetooth wireless transponder to support firmware updates and configuration updates.

Roadside controllers may be linked with lamps on stanchions to illuminate an area with a downward angled white light to provide supplementary illumination in emergency conditions

The devices 1 and 100 may be controlled by a roadside controller 150 to progressively strobe towards an accident location to help responders as they get closer to the site of an emergency.

Some roadside controllers 150 may be configured to control speakers to provide additional information at particular scenes.

The roadside controllers 150 are programmed to synchronise device LED changes precisely with transitions to increase impact of urgent messages.

In some examples, the devices 1 and 100 communicate via their mesh controllers 11 and antennae 12 to relay messages between devices. If a roadside controller 150 detects that messages are consistently hopping over a device 1 it is an indication that the device is faulty, for example by being damaged in an accident.

The roadside controllers 150 and/or the devices 1 and 100 may incorporate Radar units to detect dangerous high-speed tailgating based on speed and number of targets in a lane. The automated response from the roadside controller at the location is to instruct coordinated activation of the warning LED arrays 16-17 to provide for example "soothing breathing" illumination effects.

Roadside controllers 150 and/or devices 1/100 may in some examples incorporate a projector that projects images onto lanes, like the effects projected by lasers onto buildings. For example, if the road operator wants to deny access to the outside lane to enable maintenance, then in combination with existing messages and LED effects an 'X' pattern could be projected onto that lane (similar to "do not stop here' boxes at junctions). In other examples they can provide speed limit signs and messages projected onto the road in the same way that advertising signs painted on playing fields use the false perspective trick to show them as appearing "upright".

It will be appreciated that the system of the invention provides for secure redundant communication and control within a wired multidrop and wireless mesh network. Each device 1/100 has multiple sources of power, to ensure continuous operation of the system. These include a wired powered source (105, 120), a solar power source (30), a local battery and a centralised battery in the roadside controller so that it is not dependent on its mains link.

Each mesh controller preferably performs encryption/decryption for data transmitted to/from the devices 1/100. The controllers 150 together with the devices 1/100 form an encrypted ISM mesh network with each node capable of routing data to other nodes.

The looms 120 and 105 provide a wired encrypted multi-drop channel with the devices 1/100 being the nodes, for redundant communication between the nodes and controlled by a master node 100. The control module 11 in each device 1/100 sends commands to/from the network and to control the LED lamps 16, 17. These controllers provide a failsafe fallback condition which is activated in the case of loss of communications.

The controllers 11 perform a method for synchronising LED signalling, comprising: detecting a synchronisation signal from another mesh controller 11; transmitting the synchronisation signal to a node (device 1, 100) via one or more of the described communication links, including a wireless communication link, a wired communication link, and a GPS-based communication link. receiving the synchronisation signal at the node; actuating the LED pattern in response to the received synchronisation signal; and ensuring precise synchronisation of the LED light pattern regardless of the communication link used.

Also, each mesh controller 11 is configured to communicate information to form a digital twin of the LED pattern and associated diagnostic or operational parameters, the digital twin comprising: real-time operational data from the node; historical performance and operational data; predictive analytics based on the operational and performance data; wherein the digital twin enables monitoring, diagnostics, and optimisation of the LED signalling performance.

The devices communicate LED synchronisation signals including structured messages each including: a header indicating the type of message; a payload containing the LED pattern and other LED activation parameters such as brightness, intensity, colour (set by choice of a group of LEDs of a particular wavelength), and flashing frequency. a footer indicating the end of the message.

Components of embodiments can be employed in other embodiments in a manner as would be understood by a person of ordinary skill in the art. The invention is not limited to the embodiments described but may be varied in construction and detail.

Claims

1. A driver warning system comprising: a plurality of roadside controllers (150) arranged to be mounted near a road, and a plurality of short interval warning devices (1, 100) each configured with a saddle shape to be mounted to a central reservation barrier with a wing on each lateral side of the barrier and of a longitudinal direction, and each wing has at least one lamp (16, 17), and a top housing (10) containing a controller, wherein the roadside controllers and the short interval warning devices each has a control processor (152, 11) and an interface to communicate with each other, and the roadside controller processor is configured to transmit commands to a plurality of short interval devices to cause coordinated activation of the lamps to issue warning information to drivers.

2. A driver warning system as claimed in claim 1, wherein at least some devices each comprise a mesh controller and an antenna to relay control messages to a next successive device in a message hopping scheme.

3. A driver warning system as claimed in claim 2, wherein at least some roadside controllers are configured to identify a break in a message relay chain and to generate an alert identifying that a device is faulty accordingly.

4. A driver warning system as claimed in any preceding claim, wherein the controller of at least some short interval warning devices is configured to activate a lamp (16, 17) on a side opposed to the side of an accident to assist emergency vehicles to identify a scene of an incident.

5. A driver warning system as claimed in any preceding claim, wherein at least some short interval warning devices (1, 100) are each configured to be assembled off-site and secured as a single unit to a barrier.

6. A driver warning system as claimed in any preceding claim, wherein each short interval warning device is configured to be secured to a barrier by captive fixings (34), preventing a fixings from falling on a roadway.

7. A driver warning system as claimed in any preceding claim, wherein each short interval warning device comprises a saddle-shaped base with a top plate (31) and wing plates (32) of metal.

8. A driver warning system as claimed in any preceding claim, wherein each short interval warning device lamp comprises an LED array (37) mounted to a laterally extending support (36).

9. A driver warning system as claimed in claim 8, wherein each wing has two lamps (16, 17), one facing towards each longitudinal direction.

10. A driver warning system as claimed in claim 9, wherein each wing has said laterally extending support (36) and an LED array (37) mounted to a longitudinally facing surface.

11. A driver warning system as claimed in any preceding claim, wherein at least one lamp comprises an LED array (37) which is in a plane extending at an angle to normal to longitudinal, and said angle is in the range of 1° to 7°, preferably 3° to 5°.

12. A driver warning system as claimed in claim 11, wherein each wing has a laterally extending support (36) and an LED array (37) mounted to a longitudinally facing surface, and said surfaces extend at said angle to normal to longitudinal.

13. A driver warning system as claimed in any of claims 8 to 12, wherein each short interval warning device laterally extending support is on a lamp base (35) which is in turn secured to a wing plate (32) adapted to be secured to a barrier.

14. A driver warning system as claimed in any preceding claim, wherein each lamp (16, 17) comprises a housing (38) surrounding an LED array (37) and said housing is secured to a wing plate (32).

15. A driver warning system as claimed in claim 14, wherein each housing comprises a detachable transparent portion (39) secured to a primary housing part (38) via a gasket (40).

16. A driver warning system as claimed in any preceding claim, wherein each device controller (11) is configured to confirm if a requested action has been successfully executed or if there is an error in executing the command.

17. A driver warning system as claimed in any preceding claim, wherein each device control processor (11) is configured to perform control of light parameters including one or more of brightness, flash rate, synchronised flashing, unsynchronised flashing, and/or alternate colours.

18. A driver warning system as claimed in any preceding claim, wherein at least some of the roadside controllers (150) are configured to log and timestamp events to provide an audit log of traffic conditions and/or individual vehicle information, for retrieval should an accident occur.

19. A driver warning system as claimed in any preceding claim, wherein at least one of said roadside controllers (150) and/or short interval warning devices (1, 100) comprises radar units to detect vehicle speed and to generate warning LED activations accordingly.

20. A driver warning system as claimed in any preceding claim, wherein at least one roadside controller (150) and/or some devices (1, 100) comprise illumination projection devices to project images onto a road surface, such as images to indicate that a lane is not to be used.

21. A driver warning system as claimed in any preceding claim, further comprising a physical cable link (120) between at least some roadside controllers (150) and a short interval warning device for transmission of power and control signals.

22. A driver warning system as claimed in any preceding claim, wherein a plurality of the short interval warning devices are linked in a multi-drop physical cable link (105) running along a top surface of a road reservation barrier (B).

23. A driver warning system as claimed in claim 22, wherein each roadside controller (150) is linked by said cable link to a single short interval warning device, and said device is configured to route power and control instructions to a series of a plurality of short interval warning devices by said cable (105) secured to the barrier.

24. A driver warning system as claimed in any of claims 21 to 23, wherein the short interval warning device controllers comprise mesh controllers configured to communicate with a plurality of other devices via both wired and cable links to ensure alternative paths are available, and to signal to a roadside controller if a device is not responding.

25. A driver warning system as claimed in any preceding claim, wherein the roadside controller (153) and the short interval warning device controllers (11) are configured to communicate warning lamp control signals with structured messages, each having a header, a payload, and a footer, the payload having lamp control parameters including one or more selected from LED brightness, flashing frequency, and colour.

26. A driver warning system as claimed in any preceding claim, wherein a subset of the short interval warning devices (100) comprises a sign (102), and the roadside controller comprises an associated sign (163), and the roadside controller (153) is configured to transmit sign control messages to short interval warning devices comprising signs.

27. A short interval warning device configured with a saddle shape to be mounted to a central reservation barrier, the device comprising: a wing on each lateral side of a longitudinal direction, each wing comprising at least one lamp (16, 17), and a top housing (10) containing circuit boards with processors providing a controller and an interface, wherein said interface (11) is configured to communicate with other short interval warning devices for coordinated activation of the lamps to issue warning information to drivers.

28. A short interval warning device as claimed in claim 27, wherein the interface comprises a mesh controller and an antenna (12) to relay control messages to a next successive short interval warning device in a message hopping scheme.

29. A short interval warning device as claimed in claim 27 or claim 28, wherein the controller is configured to activate an LED lamp (16, 17) on a side opposed to the side of an accident to assist emergency vehicles to identify a scene of an incident.

30. A short interval warning device as claimed in any of claims 27 to 29, wherein the device is configured to be assembled off-site and secured as a single unit to a barrier.

31. A short interval warning device as claimed in any of claims 27 to 30, wherein the device is configured to be secured to a barrier by captive fixings (34), preventing a fixings from falling on a roadway.

32. A short interval warning device as claimed in any of claims 27 to 31, wherein the device comprises a saddle-shaped base with a top plate (31) and wing plates (32) of metal.

33. A short interval warning device as claimed in any of claims 27 to 32, wherein the device lamp comprises an LED array (37) mounted to a laterally extending support (36)

34. A short interval warning device as claimed in any of claims 27 to 33, wherein each wing has two lamps (16, 17), one facing each longitudinal direction.

35. A short interval warning device as claimed in claim 34, wherein each wing has a laterally extending support (36) and an LED array (37) mounted to a longitudinally facing surface of said support.

36. A short interval warning device as claimed in any of claims 27 to 35, wherein at least one lamp comprises an LED array (37) which is in a plane extending at an angle to normal to longitudinal, and said angle is in the range of 1° to 7°, preferably 3° to 5°.

37. A short interval warning device as claimed in claim 36, wherein each wing has a laterally extending support (36) and an LED array (37) mounted to each longitudinally facing surface, and said surfaces extend at said angle to normal to longitudinal.

38. A short interval warning device as claimed in any of claims 35 to 37, wherein each device laterally extending support is on a lamp base (35) which is in turn secured to a wing plate (32).

39. A short interval warning device as claimed in any of claims 27 to 38, wherein each lamp (16, 17) comprises a housing (38) surrounding an LED array (37) and said housing is secured to a wing plate (32).

40. A short interval warning device as claimed in claim 39, wherein each housing comprises a detachable transparent portion (39) secured to a primary housing part (38) via a gasket (40).

41. A short interval warning device as claimed in any of claims 27 to 40, wherein the controller (11) is configured to confirm if a requested action has been successfully executed or if there is an error in executing the command.

42. A short interval warning device as claimed in any of claims 27 to 41, wherein the controller (11) is configured to perform control of light parameters including one or more of brightness, flash rate, synchronised flashing, unsynchronised flashing, and/or alternate colours.