
A Ford self-driving vehicle. Photo: Calla Kessler/The Washington Post via Getty Images
Autonomous vehicle developers are pursuing different strategies and technologies — and making different claims, in different ways, about their systems. Those differences make it hard to compare vehicle safety across companies and evaluate the safety of AVs overall.
Why it matters: The success of driverless vehicles will in large part depend on how safe the public perceives them to be. That involves creating trust between riders and vehicle manufacturers — and speaking the same language about safety.
Details: Absent hundreds of millions (or more) of miles driven, it's impossible to arrive at firm conclusions about safety.
- Companies report how many miles their test vehicles have driven, without disclosing what kinds of miles, how good or bad the weather, how dense the traffic, whether in daytime or at night and so on.
Since AV crashes have been rare during development, other gauges are needed. An overarching safety framework would help to assess where an AV is in its path from early development to deployment.
- Such a framework could span different settings for testing (simulation, closed courses, public roads) and stages of AV development and deployment.
The key measurements could include:
- Infractions, tracking how often an AV violates traffic laws.
- Roadmanship, appraising whether an AV is safely navigating traffic by considering factors like the following distance it maintains and whether it seems prone to near misses with others on the road.
- Disengagements, counting when a human driver must take control of the vehicle — an imperfect measure, because drivers have different levels of risk aversion and receive different instructions from their companies, but widely used because of California’s early requirement to report them.
- Crashes and injuries, counting actual consequences of accidents or other safety events using standardized guidance for how to rate severity.
What to watch: The Department of Transportation recently updated its guidance on AVs and called for the industry to voluntarily collaborate on safety standards and best practices.
- Yes, but: Technical standards may unite the industry, but given their intrinsic generality they are not sufficient for demonstrating safety.
- A universal framework can provide a more consistent and transparent view of progress in AV safety within and across the industry, better informing the public and policymakers.
Marjory S. Blumenthal is a senior policy analyst at the RAND Corporation and a former executive director of the U.S. President's Council of Advisors on Science and Technology.
Go deeper: Read RAND's proposed framework