Written by: Michel Mondor
Vision Zero has become a rallying call in the traffic industry which has been embraced by municipalities across Canada. We see large budgets and efforts being poured into improving safety which is very encouraging. The challenge we often hear related to vision zero is that specific technology solutions to improve safety are not very prominent or available in the industry and that only a few options exist. Radar feedback signs are one of the key technologies adopted; these systems have been proven to slow cars down by making drivers aware when they are driving at speeds above the posted limits. The City of Toronto has installed hundreds of these signs as their primary traffic calming solution in order to battle vision zero over the past years. They’ve now also introduced Automated Speed Enforcement systems, but those are still very new.
This blog will discuss the emergence of new safety focused ITS systems, specifically Intelligent Warning Systems. These are often standalone systems which use sensors, beacons, and wireless communication to provide targeted hazard warnings to drivers. These preemptive warnings improve safety in areas which have proven problematic or dangerous in the past. These core technologies have been around for many years; however, recent cost reductions of solar, wireless communication, microcontrollers and LEDs has meant that these systems and their infrastructure requirements have become drastically more affordable.
Vision Zero plans focus on reducing “killed and seriously injured” (KSI) collisions. Vision Zero considers all road users but places a higher emphasis on vulnerable road users. It also follows a widely accepted, holistic approach to improving road safety which includes engineering, education, and enforcement solutions.
We are going to focus on the engineering aspect in this blog. Some sections of roadways are always more dangerous than others due to their very nature and fundamental characteristics, for example:
(1) Roadways with poor lighting and visibility conditions
(2) Horizontal curves on highways and high-speed rural roads
(3) Unsignalized intersections, especially two way stops
(4) Hidden driveways
(5) Areas with slow moving farm vehicles
(6) Road sections prone to flooding or ice formation
(7) Road sections built near infrastructure obstacles such as low bridges or EMS facilities
Very few of these dangerous road sections warrant fundamental geometric changes so the typical response is to install countermeasures. The most common countermeasure in these situations is traditional retroreflective traffic signage. But there are two fundamental flaws with the use of such signage: (1) the impact of signs on driver behaviors reduces over time as they get used to their) presence and, (2) signs do not provide any real-time situational awareness. Drivers tend to largely ignore static signs and continue driving in unsafe manners without being aware of impending dangers which may be present.
Intelligent Warning Systems (IWS) provide an affordable alternative to traditional countermeasures. Their low cost and dynamic activation means they are (1) easy to deploy, as well as (2) effective, since they only activate when a hazard is detected. In the next section we’ll review some of the most popular IWS products in the market and how they operate. Some are more sophisticated than others but each relies on those same fundamental technologies discussed above. Another thing to keep in mind is that these systems are highly customizable so they can be tuned and tweaked to fit your particular safety challenge.
The four Intelligent Warning Systems we’ll be reviewing today are:
1.Dynamic Curve Warning System
Chevron signs enhanced with solar-powered LED lights flash when a vehicle is detected exceeding the recommended speed for the horizontal curve. This has been proved to be 97% effective in reducing crashes**. These systems can be as simple as solar flashing signs with radios used to synchronize their sequential flashing. Alternatively, smart sensors can be used to activate them only when poor lighting, high vehicle speed, or ice forming conditions are present.
These systems are fully self–contained and come completely configured from the factory. All that’s needed is for them to be installed in the correct order and they will start working immediately. Replacement of signs are made easy as well with fully configured replacement units available which will automatically sync up with the system and start immediately upon activation.
2. Intersection Conflict Warning System
Intersection Conflict Warning Systems (ICWS) are another example of a smart and effective use of technology to reduce collisions on accident prone intersections. Radar’s detect the presence of oncoming vehicles on both major and minor roads and warns drivers.
Flashing LED blinkers or amber beacons get driver’s attention and helps reduce collisions. These systems are especially effective on rural intersections where slow, farming vehicles cross intersections.
There is a range of stop signs or warning signs options, all with LEDs, solar power, and radio communication, which help make these autonomous ICWS very effective in reducing collisions.
Again, this system is highly customizable such that detection and/or warning can be provided for either or both major and minor road, depending on your specific challenges.
3. Emergency Vehicles Warning System
Fire or other emergency vehicles entering or exiting their stations often face yield compliance issues from other road users. Emergency vehicles warning systems can be remotely activated using push-buttons, strobes, or hand-held key fobs inside vehicles to ensure that drivers are aware of incoming or outgoing emergency vehicles.
Not only do these emergency vehicle warning systems reduce the probability of collisions near stations but they also improve precious response time for emergency services.
4.Over-height Warning System
Old, low bridges have been a constant source of problems for road authorities in Canada. It is not always possible to easily increase the height of bridges due to restrictions of budget and other priorities.
A system to detect over height vehicles preemptively warns drivers and guides them to alternate route. This far outweighs the cost of post-collision repairs to bridges. The detection is often done through infrared sensors in combination with LED blinker signs or beacons that help get driver attention.
In conclusion, autonomous intelligent warning systems are a simple yet effective method to improve road safety quickly and at low costs. Solar power, beacons and radio connectivity help provide low maintenance, low civil construction options for road authorities. Advanced options of remote connectivity via a cell modem and video surveillance are also available for road authorities to help design and customize these solutions specific to their needs.
Many other autonomous systems such as icy roads warning systems, wrong way warning systems, and flood warning systems also provide low cost, effective alternatives for road authorities to improve road safety.