Earlier this week, a Tesla operating on Autopilot at 65 mph crashed into a stalled fire truck on the highway.
Ouch.
Luckily, no humans got hurt.
A screen shot of CBS news
“The fire truck had been parked in the left emergency lane and carpool lane, blocking off the scene of a previous accident, with a California Highway Patrol vehicle behind it and to the side,” according to the Mercury News.
The U.S. National Transportation Safety Board (NTSB) has opened the investigation into the matter.
The safety board sent two investigators to Culver City on Tuesday, while NHTSA confirmed Wednesday that it is also dispatching a special team "to investigate the crash and assess lessons learned." The use of Autopilot, reported by the Tesla’s “driver” — although this remains unconfirmed by a third party — appears to have gotten the federal agencies interested in the case.
Details remain sketchy and there are a lot of unanswered questions, since Tesla and authorities have gone mum. Nonetheless, Tesla holds the key to data that could reveal what exactly happened. “Tesla can give NTSB a ton of information because of the black box recording they do with those vehicles,” said Phil Magney, founder and principal advisor for VSI Labs.
It’s known that each Tesla has an SD card that stores all data onboard. Tesla also can access this information by connecting wirelessly with the car, unless the media unit or on board LTE are damaged. “Even if you do retrieve the SD card,” Magney said, “It will not give you the information the NTSB needs. Only Tesla can provide this, as it is highly encrypted.”
We asked automotive experts to weigh in with the questions raised in their minds — especially related to Tesla’s advanced driver assistance system (ADAS).
Let’s start with what we don’t know for sure.
Autopilot
Magney told us, “We don’t actually know if Autopilot (AP) was active or not. The driver might be blaming the accident on AP like that Minnesota case from several months ago.” In a Minnesota crash last July, the human driver initially blamed Tesla’s Autopilot, but later recanted.
Traffic-Aware Cruise Control
Mike Demler, senior analyst at the Linley Group, reminded us that “Autopilot” is actually a package of features. They include Traffic-Aware Cruise Control, Autosteer, and Auto Lane Change. "If the driver had adaptive cruise control on, I believe that a well-designed system should have detected the stoppage (in the high-speed lane apparently), but Tesla’s owners manual warns that it may not."
The Tesla's owners manual states:
“Warning: Traffic-Aware Cruise Control can not detect all objects and may not brake/decelerate for stationary vehicles, especially in situations when you are driving over 50 mph (80 km/h) and a vehicle you are following moves out of your driving path and a stationary vehicle or object, bicycle, or pedestrian is in front of you instead.”
So assuming adaptive cruise was on, it apparently gives priority to the radar and not the cameras to detect objects, Demler theorized. "That would be a software and sensor-fusion problem," he said.
Did AEB save the driver?
Magney wonders if Automatic Emergency Braking (AEB) was activated or not. He told us, “In Tesla cars, the driver can deactivate this function!” Given the car was traveling at 65 mph, this was a big hit on a very large fire truck. The impact could have severely injured the driver. “It is possible AEB mitigated the crash a bit and this how the driver could survive this,” Magney hypothesized.
Did sensors work?
Magney said, “If this was a late model S it would have a more sophisticated set of sensors, mainly camera and radar.” He noted, “The radar should have picked this up since it was in the path of the vehicle.”
Phil Magney
There is one caveat, though. Magney noted, “Radars have a lot of filtering for stationary objects because if do not, you would have lots of false positive from parked vehicles on the sides of the road or signs, etc.”
The cameras should have also picked up and classified this as a vehicle.
Next page: How far did the radar see?