Mobility players, transportation planners, regulators, vehicle manufacturers, and tech developers converged en masse upon the annual Intelligent Transportation Systems World Congress in Singapore last week. Since the early 1990’s the Congress has been an annual pilgrimage for ITS professionals, rotating venues across Europe, Asia-Pacific, and the Americas. Last year’s event was in Copenhagen, next year Los Angeles is the host.
Cooperative Connected Automated Mobility, known as CCAM, took center stage at the Congress. Across a myriad of panels and presentations, delegates wrestled with topics such as regulations to ensure the public good while also seeking to advance technology and support innovation. Others discussed the prospects of ubiquitous and lightning-fast wireless communications to support safer and less congested traffic, whether the driving is done by humans or software. Freight experts, with their laser focus on taking inefficiencies out of goods movement, debated the various pathways and pitfalls towards automated freight movement. Experts also shared their findings on best ways to inform the public and address their concerns as automated fleet services come to our roads.
City Experts Wary of Robo-taxis
An event within the event was a full day Autonomous Mobility Summit organized by Singapore’s Land Transport Authority. An intriguing panel discussion on Autonomous Mobility and Cities was moderated by Hwang Yu-Ning, Deputy CEO and Chief Planner for the Urban Redevelopment Authority of Singapore. Experts on the panel were Tilly Chang, Executive Director, San Francisco County Transportation Authority; Stefan Knupfer, McKinsey’s Sustainability Practice Global Leader; John McCarthy, Arup’s Intelligent Mobility Leader; and Stephen Cairns, Director of the Future Cities Laboratory at ETH Zurich. Addressing the mobility evolution of bikes, scooters, buses, and rail transit, robo-taxis entered the discussion with a certain tone of wariness from these city and transit-oriented experts. The discussion contrasted old school taxis and the current ride-hailing scene with the coming robo-taxis. Tilly Chang noted the flood of Uber and Lyft cars now on San Francisco area streets, many times the number of taxi’s previously. Extensive ride-hailing over-capacity has significantly worsened congestion in San Francisco, and other cities have concerns as well. Will such negative effects multiply with robo-taxis? One panelist mentioned leveling a fee on ride hailing services to achieve specific policy goals and tamp down over-capacity.
I found it curious that when the panelists envisioned a robo-taxi future, the spectre of “zombie robo-taxis” arose: predicting a world in which countless empty vehicles are roaming around looking for, or going to, a waiting passenger. As Stefan Knupfer put it, “I don’t want my robo-taxi driving continuously around the block while I have dinner.” I’ve seen this idea popping up in the automated driving media buzz as well.
Unpacking the “Zombies”
Let’s look at this more closely and add a little context. Streets flooded with ride services is the result of customer demand, not ride hailing or robo-taxis per se. The onset of ride hailing fulfilled an unmet consumer desire: ubiquitous mobility at a reasonable price and ready availability. Because of simple economics, robo-taxis are poised to replace the human-driven version.
The idea of an empty vehicle traveling around does indeed seem like a waste. But in terms of mobility services, a taxi without a rider is equally wasteful: it’s not a zero-occupant vehicle, but it’s a “zero rider” vehicle. The question is not what the vehicle is doing (or how many humans are on board) but whether a “trip” is happening. Every mile a vehicle moves without supporting a trip is inefficient. Typical taxi behavior is to park and wait, queue up at airports, or roam around hoping to be flagged down. They are out there searching for business, all the while seeking to optimize their time and resources. Similar behaviors are true for ride-hailing now and will be true for robo-taxis in the future. Empty miles (or unused seats in buses) are an unavoidable reality of any mobility service. The aim is to minimize unused capacity. The process to optimize efficiency and service quality is managed by the operator, which is either the taxi driver, a ride hailing algorithm, or a robo-ride-hailing algorithm.
Zombie robo-taxis are actually superior to a traditional taxi when moving in non-rider mode, because the empty robo-taxi doesn’t carry the hundreds of pounds of a human taxi driver, nor does it run air conditioning in hot weather. At scale, this could be an important factor in assessing sustainability. Someone should calculate the net energy savings!
The Answer is Top-Down and Bottoms-Up
City based fee structures on robo-taxis are a very promising policy tool which can encourage use of electric vehicles, less roaming, higher occupancy, and more. These costs will be reflected in customer pricing, affecting the service offerings so that the size of the vehicles and number of seats available are finely tuned to customer demand. While cities may apply such rules, be assured that the private sector operators will apply extensive engineering to minimize their “zero trip” time while moving, due to energy costs and vehicle wear and tear. Cities and operators working together are the right way to rid our streets of zombies.