I continue to be concerned about visions of an autonomous vehicle future based not only on the impressive capabilities of fully (level 4) self-driving cars but also of fleets of robotaxis replacing personal vehicles. These would, indeed, be major changes. But how soon large numbers of people will accept such vehicles, and whether they will own them or purchase “mobility as a service,” will make an enormous difference in the outcome.
We are just starting to get serious survey research data on what people think about an AV future, and the results are sobering. Fairly detailed survey research was released in April by the Texas A&M Transportation Institute: “Revolutionizing Our Roadways: Consumer Acceptance and Travel Behavior Impacts of Autonomous Vehicles.” TTI conducted the survey in the Austin, Texas metropolitan area—a far more representative location than often-studied New York City or Singapore. The study objective was “to gather empirical evidence on consumer acceptance and adoption: the factors associated with the intention to use, how that intention might influence mode choice and vehicle ownership decisions, and what all this could mean for travel demand and congestion.” The researchers did an online survey of 556 residents and followed up with in-person interviews with 44 participants.
Interestingly, respondents were split just about 50/50 on intent to use AVs, and nearly two-thirds described themselves as late-adopters of new technology. In addition, concern about data privacy was negatively correlated with intent to use AVs. When broken down by people’s current commute mode, 52% of those who currently drive to work were unlikely to be AV adopters, while 57% of those who walk, bike, or use transit were likely adopters. And while there was some correlation with age (younger people more likely, older ones less likely), the researchers found that psychological and behavioral traits were better predictors of AV adoption than demographics.
When it comes to travel behavior, 59% said that if they went with an AV, they would want to own it, compared with 41% favoring use of a shared on-demand vehicle. Interestingly, when asked to speculate on how the advent of AVs would affect the total number of vehicles owned by their household, 61% said no change, 23% said fewer, and 16% said more. On estimating the impact on their amount of travel, 66% expected the same annual VMT, 25% expected an increase, and just 9% expected a decrease. And when it came to the location of their residence, 80% expected no change, with most of the rest expecting to move farther out than their present location.
Drawing on these results, the TTI researchers then made use of the travel demand model of the local MPO, CAMPO. They tweaked a few parameters based on the idea that AVs would make travel time less onerous, ran the model, and compared the results with the status quo. The three main findings were a small increase in daily VMT, an increase in total auto trips, and less transit use. That is a long way from the utopian vision of a society where people have given up personally owned vehicles for mobility as a service, have relocated into high-density urban cores, and use transit or robotaxis for most of their trips.
These Austin, Texas results are broadly consistent with some recent international findings. In March 2015 the CityMobil 2 project in Europe convened transportation experts from the United States, Europe, Japan, and Singapore in La Rochelle, France to discuss the potential impact of AVs. After much discussion in various sessions, the experts were polled about the long-term impact of AVs in four different urban settings and for both individually-owned and robotaxi scenarios. As reported by Bern Grush and John Niles, “The direction of the responses point to more [VMT], lower vehicle occupancy, and lower ownership.” And because in most countries VMT will be increasing for demographic reasons (wealth and population), AVs “would likely make the growing problem of congestion a bit worse still.”
(This article first ran in the June 2016 issue of Surface Transportation Innovations)
