Cruise, GM’s autonomous vehicle unit, said it was pulling software and updating 80 of its robots after a crash in June.
The crash, which left two riders with minor injuries, drew national attention because it happened a day after Cruise received final approval by California regulators to commercialize its driverless robotics service.
Cruise says a regulatory filing with the National Highway Traffic Safety Administration that the software recall was issued due to a “rare circumstance” in which the automated driving system caused the driverless robotaxi — which had no human safety driver behind the wheel — to slam on the brakes, while making an unprotected left turn.
Cruise said in an emailed statement that it made the voluntary filing in the interest of transparency for the public, adding that it relates to a previous version of the software and does not affect or change its current road operations.
“The report explains how Cruise AV reacts to an oncoming vehicle speeding in the wrong lane and how, through our normal course of continuous improvement, Cruise AVs are even better equipped to prevent this unique, exceptional event.” Cruise’s statement continued.
Cruz said only one such incident occurred in more than 123,560 unprotected left turns without a driver made before the updated version of the software. Cruise installed a software update so this scenario doesn’t happen again.
IN Incident of June 3rd, an oncoming vehicle was traveling 40 mph in a right-turn/bus-only lane with a 25 mph speed limit while the Cruise AV was making an unprotected left turn, according to regulatory filings. When the robot began to make a left turn, the automated driving system predicted that the oncoming vehicle would turn right and directly into its path. As the cruise robotics braked to avoid a collision, the oncoming vehicle moved out of the right turn lane and continued straight through the intersection, colliding with the AV’s rear right quarter panel, the report said.
Cruz said the automated driving system must decide between two different risk scenarios and choose the one with the least potential for a serious collision in the moment, before the oncoming vehicle suddenly changes direction.
NHTSA a special investigation was launched — not an official investigation — into the crash. NHTSA’s special crash investigation program focuses on cases useful for investigating special circumstances or crash outcomes from an engineering perspective.