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Robin Kellermann researches mobility concepts at TU Berlin. As head of the “Berlin Mobility Data Hub” project, he and his team discover the effects of the pandemic on urban mobility using Berlin as an example. As head of the “Sky Limits” research project, he investigated the development of urban air space by drones and air taxis and presented a set of recommendations to the Transport Committee of the German Bundestag. As a co-founder of “Luftlabor”, he advises municipalities and projects that aim to implement delivery drones for the common good.
We discover in an interview with Robin Kellermann how the pandemic changed mobility in Berlin and what measures can improve it in the future. The mobility expert explains why it is important to drive social discourse about delivery drones and air taxis, as well as the sectors in which their use can be sustainable.
You have investigated the changes in mobility in Berlin during the pandemic. What did you discover and what does this mean for post-pandemic mobility concepts, using Berlin as an example?
On the one hand, we discovered that on average, Berlin’s inhabitants did not just cover shorter distances – 20 per cent shorter – but were also out less frequently compared to before the pandemic – a fall of 13 per cent. The clear loser is public transport, which has not yet recovered from the dramatic fall it suffered during the first wave, despite minor improvements over the summer months. On the other hand, the bicycle is the clear winner during the pandemic. Cycle traffic started increasing even during the first wave and tremendous growth was noted after that, particularly in the second wave in the autumn and winter of 2020. In the meantime, distances covered by bicycle per month rose by almost 400 per cent compared to the period before the pandemic. Unlike in other major cities worldwide, the car did not really benefit from the crisis based on our investigations in Berlin.
The restrictions due to the pandemic have shown that we need to find ways in the future of handling a public health crisis without falling into immobility. Private modes of transport certainly will play a major part here. In particular, the bicycle will – as our data shows – be a solution for remaining mobile whilst also being protected against infection at the same time. The expansion of bicycle infrastructure, and not just pop-up cycle lanes, as a result of COVID-19 is therefore a central element to ensure that city mobility is not just cleaner in the future, but also safer from the perspective of an epidemic.
At the same time, the trend for individual mobility must, as expected, be coupled with higher-level climate protection objectives and questions regarding the inclusiveness of the transport network. We therefore need good public transport as a key support for achieving the transition towards a sustainable transport future.
However, public transport will still have issues over the next few years reaching levels that were achieved before the pandemic started. Even if future waves are less severe or if the proportion of immunised people increases, part of the population will not use public transport as frequently compared to before the pandemic, whether this is for structural reasons, a changing work environment with more time in a home office, or for reasons of habit to avoid public transport due to the fear of being infected.
The current investigation works with a wide range of data. Where does this data come from? How can we use this data in the future to make mobility better?
We evaluated almost 800,000 traffic movements in the period between January 2019 and September 2021 that were anonymised and recorded from several hundred app users. Beyond classic data derived from manual traffic counts app-based data collection, like used in our study, provide valuable insights into current day-by-day changes whilst providing a stimulus for planning and political decisions in the traffic sector that are more focused on specific requirements. Although we will have more raw data about mobility in the future, the added value of this is clearly linked to the condition that it is seriously and clearly evaluated and that staffing capacity is created for this. On its own, data does not say much if it is not put in context, interpreted and applied in a manner that focuses on requirements.
From a technological and sociological perspective, it also focuses on vertical mobility such as drones and air taxis. You also researched social acceptance of such mobility technology as part of your “Sky Limits” project – what’s the state of play?
The use of drones for transportation purposes is considered with pronounced scepticism in Germany. The results of our representative survey in January 2020 revealed that the majority of those surveyed rejected regular use of delivery drones and air taxis. Only 25 per cent agreed that drones should be used for delivery of consumer goods and products. Only 21 per cent agreed that air taxis should be used for general personal transport. The use of drones in medical emergencies is a major exception, as this was acknowledged by a large majority of those surveyed. Around two-thirds of those surveyed agreed with their use for deliveries of medication or in transportation to hospitals.
Start-ups and companies investing in this sector also promise solutions to many current issues, such as environmental pollution and traffic jams, simply by moving traffic to low-level airspace. How scientifically viable are these promises?
Unfortunately, such promises are always expressed in extremely general terms. From a scientific perspective, they are not particularly viable or depend on a multitude of factors. Take the shortening of travel times as an example: these only apply when there are plenty of take-off and landing sites for air taxis – known as vertiports – within the city and other links between locations via road and rail tend to be quite poor. The existing battle for land use in cities mean it is probably difficult to build such a substantial network within existing structures. Moreover, initial models have actually revealed that travel times with an air taxi – particularly in the context of well-developed German traffic networks – can actually be longer than with conventional modes of transport. Finally, in the light of two to five people in an air taxi, a noticeable reduction on the road can hardly be expected. Some studies even come to the conclusion of an increase in total traffic due to additional trips to and from the vertiports.
In addition, the environmental arguments are to be noted with caution. Just because an air taxi runs on electricity does not mean it has a positive ecological balance. On the contrary, full life cycle analysis of an air taxi including the emissions behind battery production is not yet fully available. In general, the following applies: vertical mobility must focus on the same societal and traffic-related political objectives as ground-based mobility. When considering national and global climate protection objectives, it would be fatal if we were to “sacrifice” the successes behind an improved transport network on the ground for a new form of traffic in the air that does not provide a genuine contribution in assisting the revolution in transport and mobility, where we simply repeat the mistakes of earlier transport methods but as part of vertical mobility in lower-level air space.
Is society well prepared for a debate on such invasive technology, which will be ready for the market in a few years? What are the central axes of this debate?
No, not really. Whilst more has been reported over the last few years in the media about the technological opportunities offered by drones, genuine discussion across society with widespread use and the potential technological consequences has not yet taken place. This really must be seen as quite a problem. Whilst technological developments and business models are making rapid progress and politicians are increasingly focusing on drones as a technology of the future, the populace has largely remained on the sidelines during discussions. In contrast to other technological options, drones will have the features of being a public technology as they use public space and develop another completely different form of visibility and thus security. Such public technology demands for a public discussion, indeed even more it demands for a public debate about the use of lower-level air space.
Information and clarification about the degree of intrusion and the dimensions of various drone transport applications – in the spectrum of delivering consumer items to medical goods – must be a central axis of the public debate. An opinion-forming process can only take place on this basis so that democratically legitimised decisions can be made regarding the use of drones. Civil dialogue, planning workshops and future workshops could – in the same manner as with autonomous driving – work on recommendations that deliver application scenarios that could be accepted across society. Living labs for testing drones in a safe experimental environment could also be a second central axis, where the populace is involved through participatory formats, which is accompanied by sociological researchers and that create recommendations for designing drone-based applications that are most likely to be accepted across society.
How do you estimate the market and acceptance of drones and similar outside densely populated and somewhat conservative Europe? Are these not concepts for wide swathes of Africa or for rapidly developing city states in Asia?
The range of applications for drone-based transportation covers a variety of markets ranging from specialist logistics in developed industrial and service-based countries to the transport of relief suppliers in Third World countries with poorly-developed infrastructure. In short, the market is emerging everywhere in the world. While Africa could play a pioneering role in the use of delivery drones., the use of air taxis is more likely to take place in the mega cities of the Global South such as Rio de Janeiro, Dubai, Shanghai or Mexico City, as they have other traffic-related problems. Moreover, these places might have a population with higher technology acceptance (e.g. Singapore) and they might have better framework conditions to build the required ground infrastructure.
From my perspective, the use of delivery drones is generally more appealing in rural areas, as on the one hand longer distances in the countryside create more severe problems and dependencies for the supply and service sector. On the other hand, it can also be said that drones can far better use their energy efficiency advantages when applied for longer distance compared to more conventional modes of transport. In addition, the degree to which drone flights are used and the safety risks in rural usage are far lower than in the city.
Autonomous driving versus autonomous flying – what are we more likely to see here?
I think autonomous flying is more likely to be implemented a little sooner. This is not just because the technology has matured to a considerable extent, but there is also a solid legal framework that has been recently established for the use of drones. In Germany and Europe, we will soon see the first regular drone flights – particularly for medical products, laboratory samples etc. – that delivery specific logistics services autonomously. In this case, autonomous flying delivery drones should be on the scene considerably earlier than autonomous flying air taxis.
What is your personal concern about our revolution in mobility?
The traffic sector is the only sector in which CO2 emissions continue to rise. In climatic terms, traffic very much remains a problem child, which is partly to be explained by mobility behaviour being strongly characterised by enduring habits and cultural patterns. The objective therefore has to be to dramatically reduce our culturally mandated dependence on motorised personal transport and also encourage politicians to enforce their measures more courageous and more forcefully than before.