Reporting: Talking Traffic applications have a positive effect

Talking Traffic applications have a measurably positive effect on traffic flow, emission reduction and safety. This is evident from an extensive interim report that appeared in July. The study into the effects of Talking Traffic applications (use cases) will be continued this autumn.

A special feature of the study is that the data are based on data from some 1.8 million ‘random’ road users, says Vincent Habers, member of the Talking Traffic team at the Ministry of Infrastructure and Water Management. “So these results do not come from traffic models, pilot participants or staged traffic situations, but are based on data from road users using one of the certified apps.”

The study into the effects of the use cases will be expanded this autumn, both in terms of areas (more junctions and participating target groups) and in terms of numbers of use cases. According to Habers, not all the effects of all use cases could be investigated. A baseline measurement could not be taken for some applications, and a number of use cases involve ‘soft data’, such as increased driver comfort or safety.

However, the main outcome of the ‘hard’ data available is clear, such as speed adjustment, the number and duration of stops made and vehicle movements.

The main findings:

Use case 1a: In-car information on current effective maximum speed

The researchers see a significant increase in compliance with the effective maximum speed by users of the Talking Traffic information services. The effect of the information shown appears to be the strongest when the applicable maximum speed changes and if a user exceeds the maximum speed.

Use case 2: In-car information on potentially dangerous situations and road works ahead

Researchers identify a causal link between the in-car reports and speed adjustments, which contributes to road safety. More specifically: if the motorist is given an in-car warning about a dangerous situation or road works, it he/she immediately (or rather: just after the report) reduces speed.

Use case 3a: Conditional priority for specific (groups of) traffic participants at intelligent traffic lights

Although additional research with larger numbers of vehicles is needed, a first indication of priority vehicles (freight traffic, urgent and emergency services) shows a positive effect on the flow of traffic. The average travel time decreases by 7 to 10 percent compared to journeys without priority being given.

Use case 5: Optimising traffic flows through intelligent traffic lights

In two cities (inner-city and on a provincial road), a series of practical tests were performed to optimise traffic flows by adjusting the control process of intelligent traffic lights. This was done by combining existing data sources (such as data from polls) with new data sources, such as the CAM messages originating from approaching vehicles.

The effects identified proved to be in line with the locally intended policy objectives. On the N201, the researchers saw positive effects on the main route: less waiting time, better flow of traffic, fewer red-light runners and fewer stops. However, that positive effect seems to be partly at the expense of the traffic flows to and from the side streets. In Deventer, the researchers observed general positive effects on traffic flow, travel time, road safety and sustainability (fewer stops = less emissions) for, in particular, traffic to or from the side streets.

Study

The study was carried out in a relatively short period of time by Be-Mobile, that analysed data of approximately 1.8 million road users under the guidance of two external experts. There was no time in the study to use subjective user experience data alongside the objectively measured data. This will be done in the follow-up evaluation, this autumn. Habers: ‘Sometimes effects are difficult to measure. For example, motorists may have chosen a different parking space based on information in their app. But to find out, you would really have to ask them in person. In the near future, we will therefore be asking users specific questions via their app. The results will be included in the final report that will be published at the beginning of next year.

The English management summary of the interim report can be found here