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This week Utrecht has tested a new interactive green wave system for cyclists: Light Companion. This system aims to improve the flow of bikes at traffic lights, hopefully bringing an end to bike traffic jams. I went to see how it works.
Cyclists following the green Light Companion. Photo © Holland-Cycling.comCyclists following the green Light Companion. Photo © Holland-Cycling.com

Utrecht has the three busiest cycle paths in Holland: Smakkelaarsveld near Central Station, Vredenburg and Voorstraat. These cycle paths are so busy that during peak hours you often find yourself in a bike traffic jam. Over the coming five years, Utrecht City Council wants to improve the flow of bike traffic in the city. Badly adjusted traffic lights and the sheer number of them are a great annoyance to cyclists. They are also thought to be one of the main causes of bike traffic jams.

Green wave

One of the ideas to improve the flow of bike traffic is by creating a green wave for cyclists along busy roads with many traffic lights. Traditionally a green wave means that the timing of traffic lights is adjusted in such a way that if you travel at a given speed, you don't have to stop for any red lights so you reach your destination faster. However, Utrecht is going for a novel approach. Dutch innovation company Springlab has developed a new interactive green wave system for cyclists: Light Companion.

With the Light Companion system a cyclist reaches the traffic light when it has turned green. Animation © [urlb=http://springlab.nl/]Springlab[/urlb] (in Dutch)With the Light Companion system a cyclist reaches the traffic light when it has turned green. Animation © [urlb=http://springlab.nl/]Springlab[/urlb] (in Dutch)

The principle of the Light Companion system is that you don't adjust the traffic lights to the speed of the traffic, but you make the traffic adjust its speed to the traffic lights. As you come cycling along, the system detects you and calculates at which speed you need to go to catch the green light. Along the cycle path you'll see a strip of LED lights. A moving light signal shows you how fast you need to cycle to be in time for the green light. Sometimes you might have to go a bit faster, sometimes a bit slower. The chosen speed is between 13 and 20 km/h, which is thought to be achievable for all cyclists.

If you follow your 'light companion' correctly, you will always catch the green light. By guiding each individual cyclist to the traffic lights in time for the green light, they arrive at the lights in groups. Springlab hopes that this will not only reduce waiting times for cyclists, but also increase the flow for all traffic. However, unlike the traditional green wave, the Light Companion system only saves you from stopping at red lights, it won't save you any time.

To find out how the system works in a real-life situation and what cyclists think of it, Light Companion was put to the test this week on one of the main access routes into Utrecht - a busy road with separate cycle paths and a series of crossings with traffic lights. I cycled over to Utrecht to see the system in action.

Early days

I expected the test circuit to stretch at least from one traffic light to the next, so that cyclists could get a good feel of how Light Companion works. However, the test circuit turned out to be only 75 m long with a single traffic light. Clearly it's still early days for the system and the engineers were mainly focusing on technical details. While I was a bit disappointed that the scope was so limited, the developers of the system got the opportunity to see how cyclists responded to the system and try out various variables.

As I approached the site the first thing that caught my eye was a green mat on the cycle path, which turned out to be the detection system. It was interesting to see that most regular cyclists who happened to be passing by, cycled around the detection mechanism and didn't manage to activate the light. I did manage to activate the system, but then had trouble finding the green Light Companion I was supposed to follow. It turned out my timing was wrong. Luckily a test panel fared better. They kept cycling backward and forward to find out how the system worked best.

Two issues came up while I was at the test site. Firstly, cyclists found it hard to follow the Light Companion. This became even more difficult when cycling in a group. Secondly, the test circuit was too short to be able to give every cyclist a Light Companion - the traffic light in this situation only turned green every 90 seconds.

Benefits

In real life, people cycle from one traffic light to the next, preferably at a comfortable speed. For a green wave there needs to be a certain correlation between the time a traffic light is red (which is the time you have to cycle from one traffic light to the next) and the distance between traffic lights. In other words, the timing of traffic lights might need adjusting in order to make the Light Companion system work.

Clearly this interactive green wave system for cyclists still needs some fine-tuning, but overall cyclists responded positively to the idea that in future they would no longer have to wait at the traffic lights.

Personally, I struggle to get excited by a system that seems to bring little benefit. Whether I choose to follow my 'light companion' or not, cycling slower to catch a green light is not going to speed up my journey into Utrecht. I expect more result from better programming of traffic lights for cyclists or from investments in infrastructure that reduce the need for traffic lights altogether. There are many fine examples of this to be found throughout Holland.

Watch this video of the Light Companion system made during the start of the Tour de France in Utrecht.