Road studs -- also known as cat’s eyes -- are used around the world to delineate (along with painted lines) road space throughretro-reflective spheres, which are illuminated by vehicle headlights. In recentyears, the use of LED lights within road studs has been developed. This has thesignificant advantage that the road studs are: more visible due to activelighting than is achievable through reflection alone, can use dynamic coloursand can be seen at angles that would not be reflected by headlights.
These properties make LED road studs useful for locations wherethere is an increased risk of accidents such as unlit country roads.
This project aims to develop Intelligent Road Studs (IRS) combining LED lighting, sensor systems and communication technologies. The IRS will integrate renewable energy technologies that will fully or partially power the devices, making them self contained. The principle identified renewable technologies are solar photovoltaic and piezoelectric, although other sources will be investigated. Powering the units using renewable energy will reduce carbon emissions and allow for their use on sections of highway with no readily available power source.
The integration of communication technology, and for certainapplications, sensors within the individual units will enable enhancedtraffic management and driver information and this will represent thesignificant step forward over existing systems, as the lights will beable to communicate with each other and with a central control.Intelligent Road Studs embedded across the highway will create a numberof new intelligent lighting applications that will enable the moreeffective operation of the highway network, improve safety, and reduceCO2 emissions by maximising the use of the existing asset and reducingthe need for additional road construction.
The safety of the systems and the optimum positioning of the lights will be assuredthrough human factors simulation, and assessed during a period ofvalidation testing, initially of the units, and subsequently through alive trial.
Development of appropriate devices will be based notonly on the extensive combined experience within the group, but alsothrough an advisory board comprised of road operators and experts, whowill also extend the geographic range of the consortium. The potentialfor prompt delivery to market is strengthened considerably by thepresence of Siemens, who have sales channels in over 20 countries.
Cat's eyes that see the big traffic picture
Light-emitting diodes (LEDs) powered by the Sun could soon be guiding drivers. With sensors and wireless communication, they may also help control centres manage traffic patterns on a larger scale for enhanced safety.
Almost every driver at some point has come across the lines of small, reflective spheres marking lanes or shoulders when lit up by vehicle headlights.
These road studs, also known as cat's eyes, have entered a new era.
Incorporation of LEDs increases visibility as compared with reflection, provides lighting at angles not illuminated by headlights and enables use of colours to indicate different conditions.EU-funded scientists are pushing the frontiers of new technology with the development of intelligent road studs (IRSs).
Work on the project 'Intelligent renewable optical advisory system (INROADS)' (http://www.fehrl.org/inroads (INROADS)) is focused on integration of LEDs with sensor and communication systems to enhance traffic management and driver information.
In addition, the team is investigating the use of renewable energy such as small solar cells or piezoelectric devices to provide autonomy in areas without grid access and to reduce carbon dioxide emissions. Following a series of consortium meetings with the Project Advisory Group and industry representatives, partners chose to develop the technology for active lane delineation and smart pedestrian crossings.
A cost–benefit analysis of the two applications was conducted.
Scientists defined the requirements of each system, including power and lighting demands, operating temperature range, communication protocols, chemical resistance and compliance with relevant standards. To date, the team has developed recommendations of potential wireless communication technologies suitable for each application.
In addition, following testing of various sensors, one was chosen and incorporated into the sensor board design.
Careful consideration of human safety factors will provide critical information regarding the spacing, intensity and operation of the lights. Potential applications are numerous and have important implications for safety and the environment.
With wireless communication to a control centre, real-time traffic data could be used to provide advance warning of queues and minimise stop/start at traffic lights.
INROADS IRSs are also seen as a low-cost and low-carbon way to provide guidance and increase safety compared to conventional street lighting.
In addition to foreseen traffic applications, the individual technologies for LEDs, wireless communications and renewable energy should provide partners with commercial products in their own industry sectors.