Waymo simulations show how autonomous cars would have handled real-world crashes

One of the biggest arguments for autonomous vehicles is increasing road safety. Waymo today released a study that used simulations to show how its cars would have responded to real-world fatal crash scenarios.

But while we often hear that autonomous driving technology could make a dramatic difference, before today there has not been a published scenario-based study that we’re aware of that looks into how autonomous technology performs in scenarios that led to fatal crashes by human drivers.

The Alphabet division collected information on fatal incidents that took place in Chandler, Arizona — where the public Waymo One ride hailing service operates — between 2008-2017. Covering thousands of miles of road in southeast Phoenix, Waymo only reconstructed scenarios that its vehicles would find itself in today. 

The first set of scenarios (52) saw self-driving cars play the role of “initiator.” It successfully “avoided every crash by consistent, competent driving, and obeying the rules of the road.”  

Waymo then had its vehicles do the opposite and respond to accidents caused by human mistakes:

• The system avoided 82% of simulated crashes with “smooth, consistent driving” that did not require hard braking or urgent evasive response.
• In 10% of these scenarios, which all took place at intersections when another vehicle turned across its path, Waymo “took action that mitigated the severity.”
• Only 8% of responder crash simulations were unchanged since the Waymo Driver was given little time to respond. These all involved human-driven vehicles striking the rear of an autonomous car that was either stopped or traveling at a constant speed.

Waymo’s autonomous tech uses a mix of long-range and 360-degree cameras, radar, and lidar. In mitigated crashes, the company said passengers would have been 1.3–15x less likely to sustain serious injury.

In total, the simulated Waymo Driver completely avoided or mitigated 100% of crashes aside from the crashes in which it was struck from behind, including every instance that involved a pedestrian or cyclist (20 simulations in total). 

The full academic paper is available here.