Waymo Fares Best in Self-Driving Vehicle Disengagement Report

Alphabet Inc.’s Waymo unit had the lowest ratio of “disengagements” of the 25 companies that tested autonomous vehicles in California last year.

The California Dept. of Motor Vehicles requires companies approved for such testing to submit annual reports about their results. So-called disengagements occur when a back-up driver is forced to take control of a vehicle operating in autonomous mode.

A low disengagement rate suggests a system does a good job of interpreting driving conditions and making the right decisions. But safety experts also point out that such systems can be improved only when they make mistakes.

Waymo reported an average of 0.09 disengagements per 1,000 miles driven for its California fleet last year. This equates to more than 11,000 miles driven between disengagements and is down from Waymo’s 2017 rate of less than 0.2 disengagements.

Disengagements were attributed to a mix of “unwanted” maneuvers by the self-driving cars and reckless behavior by other road users.

General Motors’ Cruise Automation unit finished a distant second behind Waymo, reporting about 5,000 miles between disengagements. Zoox was next-best with 2,000 disengagements, followed by Nuro and Pony.ai with about 1,000 each.

At the opposite end of the spectrum, Apple had 871 disengagements per 1,000 miles. This comes out to an average of 1.1 miles between disengagement events.

The 2018 California DMV report can be viewed HERE.