The Evolution of Traffic Signal Technology: Past, Present, and Future

By: Miovision Team | Jun 14, 2024
close-up of a traffic light with long exposure car lights behind it

We see traffic signals every day, but how often do we actually stop to think about how far their technology has come in our lifetime? 

Today’s optimized traffic signals are making roads safer than we likely ever thought possible. What began as simple tools used to tell drivers when to stop, have evolved into complex traffic light technology powered by machine learning. 

In this blog, we’ll unpack the long history of traffic light systems, exploring the past, the present, and, of course, the future.

The History of Traffic Signal Technology

The first traffic light control system was invented in 1868—for horses!

British railway engineer J.P. Knight is credited with its invention, as he sought a way to manage the flow of horse-drawn carriages and pedestrians in London, England. His invention was very different than the lights we know today; it used gas lamps at night and a semaphore system operated by police officers.

Officers stood in the middle of the road during the day, raising and lowering the semaphore flags to grant or deny passage on a given roadway. At night when visibility was low, they instead lit the gas lamps—green for “go” and red for “stop”. 

Unfortunately, as you probably expected, burning gas lanterns in the dark led to many accidents and injuries. Having officers stand in the middle of the road during the day also proved dangerous, especially with the advent of cars.

Concerns about this traffic light control system paved the way for American police officer Lester Wire, who developed the first “modern” traffic light in 1912 in Salt Lake City, Utah. His system worked on the side of the road, using electricity to power red and green lights as well as a buzzer that beeped to indicate an impending signal change. 

His design was first installed in Cleveland, Ohio in August of 1914. 

What About the Yellow Light?

We got closer to a smart traffic light in 1920 when Detroit police officer William Potts invented both the three-color system and the four-way design.

Yellow, the third color we have come to expect in modern traffic lights, was added as a means to improve Wire’s warning buzzer. Four-way signal lights were first installed on Detroit’s Woodward Avenue, which, after also becoming one of the country’s first paved roads, has gone down as one of America’s most famous roadways. 

Detroit remains a traffic innovation hub to this day.

a smart traffic light showing yellow
Image Source: Canva

The Present State of Traffic Light Systems

Fast forward to today, and the traffic signals guiding traffic on major city streets are not all that different in design than the ones Potts implemented. 

Navigate the streets in any major city today and you’re still likely to see the now tried-and-tested three-color layout, as well as the four-way design that redefined intersection traversal and safety. Further changes have been more so to the way signals are controlled rather than their physical construction. 

Traffic signals first became computerized in the 1960s. Further advancement in computer technology—paired with the ability to monitor traffic—led to them being programmed on fixed schedules to meet traffic needs. Now, traffic signals can even be controlled differently depending on weather conditions or increased traffic volume. 

In the 1990s, some countries began incorporating countdown timers on their traffic lights that told pedestrians how long they had before a switch. 

Yet, as we all know, the current state of traffic light systems leaves a lot to be desired. 

You would be right to feel our supposed “smart stop lights” are never in sync, as congested traffic flow makes road traversal extremely tedious. No one would fault you for feeling as though our current-day signal lights are stuck in the past. 

Enter smart traffic lights

The Future: Smart Traffic Lights

Smart stop lights are the future of technology, and, in some cases, have already arrived to make roads and intersections more intelligent. 

Through a combination of sensors, video cameras, and advanced machine learning algorithms, smart traffic signals empower professionals to monitor traffic in real-time and adjust signal timings accordingly. A smart traffic light system can reduce travel times, cut down on emissions, and improve safety for all kinds of road travelers.

Smart traffic signals are the key to enhancing public transit. Many avoid taking buses due to the perceived reliability of arrivals, but much of those delays can be attributed to poor signal management. As such, smart traffic signals unlock better and more efficient route planning for public transit to improve the rider experience. 

Another benefit of a smart traffic light is its preemptive capabilities. For example, Emergency Vehicle Preemption (EVP) systems allow connected signals to give priority to first responders rushing to a scene. Unlike traditional signals, these use a predictive traffic light algorithm that reduces both costly delays and dangerous accidents. 

What we have now is only the beginning. New advances in machine learning and monitoring technology continue to open doors for further innovation. As algorithms become more precise, the road experience for drivers will only continue to improve. What started as green and red lamps has quickly become smart stop lights driven by data!

a stylized shot of a traffic signal at street level
Image Source: Canva

Smart Traffic Light Systems With Miovision

The history and evolution of traffic signal technology is an outstanding feat of human ingenuity and engineering—and the best is yet to come with smart stoplights.

Miovision is a leading provider of smart traffic management systems that are enabling cities to get more out of their road networks. From remote monitoring to EVP, our family of offerings is redefining what smart traffic lights can do for all travelers. 

If you’re interested in learning more about how Miovision systems can work in your municipality, we encourage you to reach out to our team. We’ll be happy to answer your questions and even book you a demo as needed. 

Contact us today to get started!