Arriving soon, Driverless Airport Shuttles!
Like for so many other forms of transport, autonomous vehicles or semi-autonomous vehicles are starting to offer an alternative to traditional airport shuttles. David Holdcroft, Head of Airport Systems at SYSTRA Aviation, tells us about this innovation.
A frequent sight at many airports since the early 1970s is the APM (fig. 1) or Airport People Mover. These large, self-driving vehicles (50+ passengers per car, often coupled into “trains” of 2 or 3 cars) trundle up and down on their dedicated guideways between terminals, car hire facilities or remote satellites, happily moving large numbers of people between a few stations quickly and efficiently.
As for so many other forms of transport, autonomous vehicles or semi-autonomous vehicles are starting to offer an alternative to APM. Autonomous Shuttles and other systems such as Personal Rapid Transit (PRT) are already here and operating. Let’s look at what they can offer.
Firstly, what is available?
PRT is Personal Rapid Transit (fig. 2) – as the name implies 4-6 seat small vehicles which transport you on your own or in your group (like a taxi);
GRT (Group Rapid Transit) or Autonomous Shuttles are generally electric minibuses carrying between 10 to 24 passengers.
It should be noted that they are systems and not just a vehicle which you buy and let loose on the road. Depending on who you buy the system from you will get not just the vehicles but guidance and supervisory software, possibly a guideway and, optionally, even the operation and maintenance.
There are a number of suppliers in the market, for example: Navya, EasyMile and 2getthere, all with a slightly different take on the basic concept, but in general they tend to be battery powered, have a top speed of between 18-20 KPH (but potentially up to 40KPH if the safety case allows) and use a central supervisory system. They are also increasingly able to use the existing road infrastructure.
Current systems such as those in use at Heathrow Airport and Rotterdam (Riviuum) can guide themselves along a predetermined route. Mechanical guidance like that used for an APM is not needed, but they do require some form of assistance for localisation and navigation. GPS can help but is not always used or accurate enough (GPS can be affected by weather and buildings and some areas do not have good coverage). Each provider uses a slightly different method. 2getthere for instance relies, in part, on magnets embedded in the road or guideway. All the systems have redundancy and safety at their core.
Some systems can monitor their surroundings for pedestrians and cyclists etc. and respond accordingly, for instance slowing down or stopping. Systems now being designed and deployed will also be able to run in full mixed traffic on public roads. The speed they can do this will, of course, depend upon local traffic speeds, according to the maturity level of the technology.
Each deployment is unique and will require its own dedicated safety case which considers and mitigates the risks in that particular environment. This might, for instance, require the removal of parked cars along the side of a road to eliminate the hazard of pedestrians suddenly appearing from between the parked vehicles.
The autonomous systems (PRT and Autonomous Shuttles) now available have some advantages over traditional APM, and in many ways do a quite different job. They can, for example, offer a more frequent service at many more stations/stops, getting closer to the origin and destination of the passenger’s total journey. This reduces overall journey time.
Having the vehicles run independently, to increase journey time predictability, away from road traffic, requires that the vehicles have their own dedicated track or guideway. This of course introduces its own cost! If it’s just a matter of zoning off a lane on an existing road then this cost is minimal. However, if elevated guideways are needed, this becomes more expensive. To mitigate that the guideways can be light weight (for the smaller PRT, the structure can be designed to a standard lower than that required for classic infrastructure e.g. footbridges).
Autonomous Systems can also run an “on demand” service during quiet times or deviate from their core route to suit fluctuating or ad-hoc passenger needs. As long as these optional routes/stations have also been mapped and programmed into the supervisory system, then it will only serve them when a passenger requires them, saving unnecessary journeys and thereby reducing operating costs.
Of course, it’s not just passengers that need to be transported around an airport. Other items such as baggage, food and other goods must be delivered, and waste removed. Autonomous Systems using specialist vehicles can help with this, perhaps connecting a centralised consolidation centre to the terminals, or serving baggage drops located in car parks, where passengers check their bags in just after parking, allowing them to travel unencumbered to the terminal, or even for automated transportation of baggage transfers between terminals.
In comparison to APM, Autonomous Systems offer a lower capital cost solution with more flexibility to serve a wider area and provide several different functions besides carrying passengers. They are also easier and quicker to extend or adapt.
Airports, a suitable field for high-tech experimentation
Airports can lend themselves well to the introduction of new technologies and are often early adopters. In the case of Autonomous Systems, they offer several advantages over an urban deployment. For instance:
• Airports are their own landlord, typically have a single entity in charge of decision making and planning, and the geographical perimeter has clear boundaries; this makes progress easier and faster;
• They do not have as many different use cases, e.g. types of passenger, as a city would due to the limited campus and range of activities, making the design and operation of Autonomous Systems easier.
All this makes it relatively straightforward for airports to adopt Autonomous Systems. In fact, several airports including Heathrow, Brussels and Paris have such systems or are going through trials now.
So, what would an airport that employs Autonomous Systems look like in a few years’ time?
It could have a network of intelligent shuttles running only when needed, on the routes where there is a demand, delivering passengers in a shorter predictable time to their destination. Passengers would be able to check their bags at convenient bag drop facilities in remote car parks with shuttles delivering the bags (securely) to the terminal baggage system. Goods and waste could be carried on the same system, taking vans and trucks off the airport roads.
All this can be done with an automated and electric system.
This all sounds a long way off, but some airports are using or trialing Autonomous Systems now!