In the major city of Aarhus, Denmark, Road users are now reaping the fruits of Bluetooth monitoring, with shorter, more stable travel times, as well as benefiting from digital signs that help them make informed decisions.

If you drive around Aarhus with a built-in/switched on Bluetooth device, you will automatically be helping your fellow motorists to enjoy a faster and less congested journey. Aarhus Municipality, the second largest city in Denmark, has been using intelligent sensors that detect motorists’ mobile devices for several years. The data collected is used to gain an in-depth insight into and an understanding of traffic flows and the development of traffic jams, in order to optimise the road network and reduce congestion.  

Travel time savings and shorter queues
The municipality can demonstrate significant travel time savings as a result of a host of new initiatives and optimisations, using data from the small, Bluetooth-detecting sensors. A striking case in point: 

  • After the expansion of two new turning lanes and optimisation of the traffic lights at the Skanderborgvej/Ringvej Syd intersection, a travel time saving of a massive 81 hours a day has been measured!. This travel time saving has been calculated solely on motorists travelling through the intersection during rush hour periods – morning and evening – and the total saving for the entire day is undoubtedly higher.
  • At the heavily trafficked Viborgvej/Runevej/Bredskiftevej intersection, the sensors have measured an average time saving, heading out of town, of as much as 31% between 3 pm and 5 pm. Travel time has also become far more stable. Where, on some days, it would take motorists around 6 minutes, the travel time is now more constant at around 2 to 2½ minutes, regardless of the time of day. This gives commuters far greater predictability.
  • With the introduction of a new left turn filter arrow from Søren Frichs Vej onto the ring road (Ringgaden), sensors have been able to detect a reduction in travel time of more than 50%.

“Previously, drivers could easily sit in a queue for 10–12 minutes to turn left onto Ringgaden. With the new left turn filter arrow, it takes two to four minutes during rush hour,” explains Asbjørn Halskov-Sørensen, project manager at Center for Byens Anvendelse, CBA (the Centre for City Use).



Informative traffic signs work as intended
Last year, Aarhus Muncipality also erected 10 variable message signs on the stretches affected by light rail work, primarily Kystvejen, Randersvej and Grenåvej.

The signs, which provide information on travel times, fastest routes and other traffic information in real time, are also driven by data from the sensors. The information displayed is continually updated, in step with the actual behavior of road users. So, by considering their route and the time they set off, the motorists themselves are helping to keep the traffic moving.

A recently conducted survey shows that commuters appreciate this continuous information, which most feel makes for a more pleasant journey. Other feedback tells us that drivers become less stressed when they know in advance what to expect, traffic-wise.

The survey also shows that commuters trust the information on the signs and choose their route based on the data presented to them on their journey to and from work. Two signs out towards the E45 (state highway) reap particular praise from motorists, who find the information about the journey home especially useful.

Precise figures are crucial

“Being able to give people concrete figures – both to our politicians and to our road users – provides the basis for a far more objective and balanced debate on the things we do on the roads,” says Asbjørn Halskov-Sørensen. “It is important for us to be able to document the facts when residents and the business community address themselves to us, or further up the system, because they are experiencing long travel times/queues on various stretches. These experiences are often subjective, and travel times therefore tend to feel longer than they actually are.”

Danish Technology
The solution used by Aarhus Municipality is called BlipTrack and is produced by Danish BLIP Systems.

“The technology works by the 200 or so sensors, which are set up in and around Aarhus, detecting when a hands-free phone, mobile phone or another open Bluetooth device drives past. This allows the BlipTrack solution to calculate travel times, congestion and traffic flows,” explains Christian Bugislaus Carstens, BLIP System’s marketing manager. “The sensors do not pick up any sensitive personal information, only the device’s unique ID, which is not registered in any registers. The unique ID is also encrypted in the sensor, making it impossible to identify the Bluetooth device afterwards.”


“BlipTrack data is generally used for much more than just being able to measure the effect of signal optimisation and roadwork/construction projects, but this is clearly an important part of its application, and something from which we have benefited greatly. Ultimately, the data contributes to an improved economy and a better environment through reduced travel times and fuel consumption, and thus reductions in greenhouse gas emissions from vehicles,” says Asbjørn Halskov-Sørensen.

The future of traffic in Aarhus

“We are in the process of designing a travel time index to show how the travel time on the main approach roads and ring roads develops year by year, in the same way that we already have an index for the development in traffic volume from year to year. We expect this to be a really useful tool, enabling us to monitor and achieve the political goals set for travel times on our road network, as well as to take action at the spots where travel times have begun to increase beyond acceptable limits,” says Asbjørn Halskov-Sørensen. “In addition, we are having BlipTrack software developed to monitor the travel times of the different segments, and to raise the alarm if the travel time significantly exceeds the norm for that time and that day. We expect this to allow us to be far more on top of the situation on our roads and, for example, to be able to resolve any technical issues with traffic lights quickly.”

Ever-increasing international travel volume is having a serious impact on airports like New Zealand’s Auckland International, which saw over 19 million passengers last year. The airport is taking the increased passenger flow and logistics issues seriously, using a unique combination of traffic and passenger flow measurement technology. The result? Faster travel times, acceptable wait times, less passenger stress and a wealth of information that helps the airports and the city to plan resources more effectively.

Auckland - a growing hub for travel

Auckland Airport expects to host over 40 million passengers annually by the year 2044. To cope with this increase in passenger load, the airport embarked on a wide-ranging and world first combined passenger-flow and road-traffic measurement project, with the goal of obtaining real-time cohesive view of people movement patterns, to guide daily and long-term operational decisions, maximise capacity and improve flow.

In its build, the airport has opted to aim for sustainability, while ensuring that they will not only have the capacity to handle the extra people, but also the capability to make the passenger journey as smooth and stress-free as possible.

Keeping things flowing

Smooth passenger flow, both in the arrival and departure terminals, and the concession and transit waiting areas, as well as on the roads surrounding the airport, is critical to the successful operation of an airport.

Issues with traffic flows can result in delays for passengers, airport staff and airline crew, resulting in disruptions to airport and airline operations.

To manage both passenger and traffic flow, Auckland Airport realised they needed to have a bird’s-eye view of the entire system, as well as detailed, up-close analysis of ongoing issues. They also needed a way to quickly act when things start to bottleneck.

With several traffic monitoring projects in New Zealand, using the same technology, infrastructure consultants Beca was commissioned to extend the solution across the airport’s roading infrastructure. This now provides the airport with a seamless picture of traffic flow information between the airport and Auckland CBD (Central Business District, also called the city centre).

How it works

On the Road

Outside the airport, the solution measures traffic flow between the CBD and the airport, providing real-time data on reliability, vehicle counts and travel time.

It provides data about the mix of staff and passengers using the Park and Ride facility, enabling the airport to better understand the performance and regularly review how they can improve their facilities. This information is also analysed to help planning decisions for road network maintenance and infrastructure projects.

The insights, collected using a range of technologies, including radar and WiFi sensors, also helps the New Zealand Traffic Agency (NZTA) to make informed traffic management decisions, and has allowed for the implementation of a number of initiatives to improve the traffic flow to the airport. This includes optimising traffic signal timings, and  combined with the recent opening of the new constructed Waterview connection, has resulted in significant travel time cuts to and from the airport from the CBD and West Auckland.

In addition, the real-time and historic BlipTrack data enables NZTA, via their new app RideMate and online, to display live travel times between the CBD and airport, as well as informing about days with high risk of congestion. This enable road users to plan ahead, reducing both the risk of travellers missing their flight and airport employees coming in late for work.

Besides the benefits of real-time reporting, the historical data is used to detect driving time anomalies. Effectively, this means that the solution can pinpoint road sections and intersections where driving times deviate from the norm as a result of construction projects, incidents, roadwork, faulty traffic lights and other factors. With this information at hand, real-time traffic management can take place.

Richard Young, Senior Associate at Beca, says: “The intelligence that BlipTrack is delivering has already proved its value, by providing automated alerts on delays on vulnerable corridors, real-time counts on traffic flows and delays, and intelligence on the origin and destination of vehicle movements into the airport and to terminals and car parks.”

In the airport

Inside the airport, the solution provides metrics on passenger queue times and volume, as well as insight into passenger movement patterns throughout the international and domestic terminals´ departure and arrival processes.

This helps the airport better manage and support resources by focusing on high-demand locations and periods. Likewise, the data directly benefits passengers by displaying wait times at security checkpoints, managing passenger expectations and reducing queue-related stress.

Mark Croudace, Manager – Operations at Auckland International Airport, says: “BlipTrack was a critical investment. The data has provided valuable insight into our operational performance across both our assets and processes. Most importantly, it has enabled us to have meaningful conversations with our key operational stakeholders and vendors, as we collectively seek to improve the passenger experience.”

Changing the face of travel

Numerous other international airports, including Amsterdam Schiphol, Copenhagen, Dublin, Brussels, Bristol and Billund, are following suit. These airports have recognised that comprehensive seamless passenger flow data is indispensable in guiding physical expansion plans, and for streamlining operations to accommodate rapid passenger volume growth, without compromising the passenger experience.

“By having Auckland Airport and Beca working together, and by sharing data between multiple solutions, BlipTrack provides a solution that no other product in the industry can currently reproduce – large-scale, seamless, door-to-door movement management between different modes of transport. And because it´s not only limited to certain areas, it can be considered as one of the first real, tangible steps to true multimodal traffic management,” ends Peter Knudsen, CEO of BLIP Systems.

Besides providing airports around the world with seamless passenger flow data, the solution is employed in optimisation efforts in road traffic applications in Switzerland, Thailand, Canada, the UK, Denmark and Sweden. In recent years, it has been rolled out in ports, train stations, ski resorts, amusement parks, and at events around the world.

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Auckland Airport Take to the Streets to Boost City-to-Gate Passenger Experience.

“The benefits we have gained from the BlipTrack solution since implementation are very significant. We now discover errors and irregularities that we would not have a chance to see otherwise. In addition, it is extremely educational and easy accessible to study how the incidents of various kinds influence the road network.”

Asbjørn Halskov-Sørensen

Project Manager at Aarhus Municipality

“The BlipTrack solution helps improve service levels for the municipality commuters. The real-time travel time and wait time information allows drivers to make informed route choices that ultimately distribute traffic and increases the operational performance of the road network.”

Anders Kruse Christiansen

Project Manager at Aarhus Municipality