Passengers have long loathed airport waiting lines. But, in the age of COVID, cutting queues is no longer just a matter of keeping travellers happy, finds Paul Willis.

The pandemic and its impact on the airport sector rumble on. As does the need to ensure social distancing requirements and keep bottlenecks to a minimum.

This in turn has led to airports prioritising queue management technologies, Florian Eggenschwiler, chief product officer at the Swiss crowd management tech company Xovis, recently told Airports International.

According to Eggenschwiler, while “overall investment by airports into technology has gone down” because of the sharp revenue declines resulting from the pandemic, “a disproportionate amount of investment has still gone into queuing technologies”. Proof of this can be seen in the number of airports that have invested in queue management solutions in recent months.

Last November, for example, the USA’s Philadelphia International announced the roll-out of a queue management system providing real-time passenger wait times in Terminal D/E, with plans to expand it to the rest of the airport by 2023.

At the same time in the UK, London Gatwick unveiled an AI-based passenger flow solution provided by the technology firm Veovo. More recently, Stateside, in January 2022 Denver International announced the implementation of a queue management solution provided by Silicon Valley start-up LiveReach Media.

Broader uses

The need for these technologies is not just a response to social distancing requirements, said Eggenschwiler. Since the outbreak of the pandemic, airports have also been grappling with staff shortages, brought on in the first instance by large-scale lay-offs and then, as passenger numbers began to rebound, “airports haven't been able to onboard staff as quickly as they would have liked to,” he explained. The other main reason why Eggenschwiler thinks there has been considerable investment in these technologies is because of the impact of COVID-era travel requirements, such as health documents, additional visas and travel authorisations.

“This has led to significantly higher processing times, especially at check-in but also at other touchpoints,” he said. “This has posed significant challenges for many airports because while traveller numbers might only be at 70-80% of 2019 levels, people are spending so much longer in the terminal that, especially during peak hours, terminals are already full.”

Xovis’ queue management technology, which is now installed in more than 100 airports worldwide, helps airports manage these issues through the use of 3D stereo vision sensors mounted in the terminal ceiling.

Consisting of two lenses, the sensors are able to “perceive the world beneath as a 3D image,” said Eggenschwiler. They detect individuals who are then anonymously tagged and tracked as they move. By linking the sensors together, psychological difference whether you see a long queue and you freak out about missing your flight or you see, okay, it's 20 minutes, then you can calculate that you have enough time to go through.”

People movement

Besides the passenger experience, queue data can be useful to airports for other reasons. One is to “optimise load balancing”, according to Eggenschwiler. In other words, ensuring that some touchpoints are not being overloaded while others are being under-utilised. Similarly, the data can be used to help manage staffing levels.

In airports where the management of the security zone is outsourced, the data also helps airports monitor the performance of third-party providers where minimum wait times are a condition of the providers’ service agreement.

These different uses can be broken down in to two broad categories, said Raul Bravo, CEO and co-founder of tech company Outsight, based in Paris: “The first is leveraging the data in real time. So, for example, you set up a threshold – like a maximum density of people in a given area – and whenever the threshold is exceeded it triggers some kind of a response, like an announcement over the loudspeaker. The second way is to look at the data over time to analyse trends.”

The benefits of Lidar

Outsight’s crowd management technology, which is deployed at Paris Charles De Gaulle airport, uses Lidar, a laser-based 3D imaging tool most commonly known for its use in autonomous vehicles.

According to Bravo, Lidar is well-suited to queue management for two key reasons: “The first is that Lidar gives you a really clear picture of where things are.

“It gives you the shape, the size, the velocity and the position of an individual with an accuracy you cannot really have with cameras.

“Secondly, it is automatically anonymous. With a Lidar image, you cannot know who it is, you cannot even tell gender,” he explained.

Outsight isn’t the only company offering Lidar-based queue management technology. Another is California-based tech provider The Indoor Lab.

According to The Indoor Lab co-founder Patrick Blattner, he was the first to bring Lidar in to the airport space, with a project at Denver in 2016.

At the time, Blattner and his co-founder were working for another tech company, developing people tracking solutions that relied on a range of technologies

– Bluetooth, Wi-Fi sensors, optical and infrared cameras. However, they were so impressed by the capabilities of Lidar that they decided to start The Indoor Lab to take advantage of the opportunities offered by the technology.

Since then they have implemented Lidar-based tracking solutions at a number of airports including Florida’s Orlando International, at the height of the pandemic in 2020, and at Dallas/Fort Worth in the past year.

For the Orlando project they were asked to track passenger movement in a 50,000sq ft area of Terminal 2. Because the terminal is flanked by windows on both sides and has an atrium overhead “at different times of the day you've got a lot of different sun reflectivity that happens” explained Blattner.

“With conventional cameras reflectivity like this can blind the camera from distinguishing a human over a shadow,” he added. “That's why in the past we had to then bring in infrared cameras to pick up heat signatures.”

To pick up accurate heat signatures, he said, the infrared cameras have to be mounted directly overhead. For the Orlando project this would have been difficult because of the low ceilings in Terminal 2.

All this becomes a non-issue with Lidar, though “because it's a horizontal field of view, so you basically set it up at [a height of] about 8ft” explained Blattner. The horizontal mounting also means that a single Lidar camera can track a much larger area than an overhead camera.

For the Orlando installation, for example, they were able to cover nearly the entire 50,000sq ft space with just seven cameras.

The sun reflectivity is also a non-issue with Lidar, whose ability to track people is unaffected by light conditions. “It's a game changer,” said Blattner.

The versatility of Lidar means that it can be used outside. Blattner and his team are currently installing their hardware at two outdoor sites at Dallas/Fort Worth for queue management purposes. The first

is to help the airport monitor queuing levels at the bus pick-up.

Blattner said: “In some areas, travellers are not able to get on the bus because the buses are too small and overcrowding occurs at different times of the day and week. So we're deploying Lidar in the next 30 days to carry out measurements.”

The second deployment is at the car toll plaza at the airport exit where congestion levels at peak times are leading to wait times of up to 90 minutes.

Software-driven solutions

The solutions detailed above require hardware (cameras and sensing technologies) as part of their installation. But there are some queue management systems that are entirely software-driven.

One such Software as a Service (SaaS) solution is the system developed by the French tech start-up Smart Flows, which works by leveraging existing network infrastructure – Wifi, Bluetooth and airport cameras – to collect travellers’ phone signals in real time, using them to track the traveller through the terminal.

A key advantage of a solution like this is the lower investment costs for the airport, according to Marie Faucon, marketing manager at Smart Flows.

Faucon told Airports International: “There is no CAPEX [capital expenditure], it’s just pure software. So only OPEX [operational expenditure].”

The software ensures airports can maintain GDPR compliance by only collecting smartphones’ media access control (MAC) address, a unique identifier that Faucon said “is anonymised as soon as it gets to our software and our databases”.

However, the software cannot provide the same granularity as the sensor-based solutions offered by Xovis, Outsight and The Indoor Lab; it cannot give an exact position of each individual. Instead, said Faucon, it gives “an approximation of the number of people that are in an area”.

The accuracy of this approximation is routinely verified by Smart Flows using external data from the airport, she said. Smart Flows’ solution is in operation at Riyadh, Montréal and Hong Kong airports, among others.

While the data collected by these technologies is proving vital in queue management, it has many other potential use cases for airports, Faucon pointed out. She offered the following example: “If I see that one device is disappearing from the Wi-Fi infrastructure at 1400hrs at Gate B and I know that at Gate B at 1400hrs there is a flight to Paris, for example, the software is going to tag this path as the path of somebody flying to Paris.”

With this data, the software can identify all other examples of travellers departing to Paris and track their movement through the terminal.

From the data, an airport can build up a picture of the behaviour of passengers flying to Paris “which is going to be rather different from the behaviour of passengers travelling to Los Angeles or New Delhi”, Faucon noted.

“This allows you to refine the quality of the service that the airport is going
to provide for the passenger, meaning ultimately that they can offer a better experience at security, at check-in and in the retail and food areas,” she explained. “This is a very interesting added value for our customers.”

Image: Outsight

This feature was originally published in Issue 1, 2022, of Airports International.