Improving traffic flows without building
new roads

The city of Vienna optimises traffic flow with
PTV Optima.

Estimated reading time: 2 minutes

“Technology provides a cheaper, quicker and better solution to the traditional reaction to traffic jams – that lane capacity must be increased either through widening or building a complete new road”, says Devrim Kara, Director of PTV UK & Ireland. More roads too often lead to more and longer traffic jams. This is why we need a smarter approach. In his article for Smart Highways, he describes how cities optimise their road networks with intelligent transportation systems (ITS) to better react to changing conditions.

Using historic data to create models of typical day or peak periods is just the first step because reliable predictions need real-time data: “The model constantly takes in real-time data from that moment’s network conditions and helps the operator to predict the best scenarios to manage that particular demand. For the first time, the traffic manager in the control room can really benefit from the expertise of the traffic modeller. Despite the two professions being so clearly linked, historically modellers and operators have acted separately. Modellers have taken plans for a road network and data about it to help plan future changes. Operators have then been tasked with managing the network they have been given. Now a roads operator can increase capacity by using infrastructure on site or other mechanisms available such as ITS or even providing predictive information to motorists directly into their in-car satellite navigation systems or smartphone apps.

Filling in the blanks
The model-based approach is very good also at eliminating certain biases in real-time data, such as lack of data in specific geographic locations or small sample sizes (for example, a single delivery vehicle stopping can incorrectly suggest a traffic jam). Also, when there is a complete absence of data for a road, the model can “fill in the blanks” but predicting likely demand based on the conditions of roads around where data does exist. This is an important improvement to the operator’s ability to manage traffic on a network in the most optimal way.”

Read on to find out how the city of Vienna benefits from real-time traffic management with PTV Optima and why dynamic switching helps reduce journey times and emissions: Smart Highways: Optima-ising the network