Bruce Mehler Presents on Autonomous Vehicle Signaling for UN Forum on Auto Safety

AgeLab Research Scientist Bruce Mehler gave a presentation at the United Nations Economic Commission for Europe’s Global Forum for Road Traffic Safety on some arguments against developing tools of signaling in automated vehicles for other road users.

Optical signals in cars with driver assistance systems (e.g., a flashing light on top of the vehicle) would be intended to signal whether a human being or a technological system is in control of the vehicle at a given time. Such a functionality would be useful, in one instance, for law enforcement officers, so they can understand who is in control of a vehicle in order to ascribe responsibility for violations of roadway rules and understand the causes of roadway incidents.

One argument that Mr. Mehler mentioned against developing such a signal is adding another informational cue onto roadways may draw attention away from other events and increase confusion on roads. Another issue is that, in semi-autonomous vehicles, driving status can evolve over time. A vehicle may be in an automated mode at the start of a critical event, but in manual control at another stage of the event. For law enforcement officers attempting to evaluate responsibility in a crash situation, this variability may pose challenges for their ability to interpret an optical signal in relation to the crash event.

An alternative option to optical signaling for law enforcement officers is an “interrogation port” that allows them to access, in a post-hoc manner, the data on autonomous system usage in the wake of a roadway violation or accident. Issues for this implementation include informational clarity – what, and how much, data does an officer need to interpret a situation? – cost, and privacy concerns.

A final and more fundamental concern that Mr. Mehler raised was on the very notion of responsibility as it pertains to technological systems. At what level of involvement can we say that an autonomous system is “responsible” for the driving behavior instead of the driver? At one point after a takeover request from a system does a driver take on responsibility? These questions are relevant both for the development of an optical signaling system for autonomous cars and in general for interactions between drivers, driver assistance systems, and the law.