MADISON, Wis. — EE Times has obtained from the Tempe (Ariz.) Police Department the report of a traffic collision involving an Uber vehicle on March 24.
The full report tells a story different from earlier, sketchy accounts of the crash. It also reveals details that might prompt more questions about Uber’s actions — or inaction — at the intersection where the accident occurred.
EE Times got the help of Mike Demler, senior analyst at The Linley Group, to decipher the police report.
Before getting into detail, here’s a recap what we reported before:
Until police info became public, the prevailing press narrative, including this publication, was that the crash resulted when the driver of a second vehicle “failed to yield” to the Uber car while making a left turn.
Observers were quick to conclude that this was an accident caused by a reckless “human” driver. Uber — which was in self-driving mode — was not at fault.
Intersection of South McClintock Dr. and East Don Carlos Ave. where the Uber accident took place on March 24, 2017
When we put together statements by drivers and an eyewitness included in the police report, we begin to see a different picture.
First, the driver who hit Uber’s Volvo was in the intersection waiting to turn left and was therefore moving slowly. She wasn’t exactly making a sudden, reckless move.
Second, Uber’s Volvo, in self-driving mode, was moving at 38 mph in a 40 mph zone and failed to detect the left-turning vehicle. Further, although the Uber’s driver remembers the traffic light changing to yellow when his car entered the intersection, the Uber Volvo didn’t react, neither hurrying nor hesitating.
Fortunately, nobody got hurt. After a dormant weekend, Uber announced that the company has resumed its driverless pilot project, picking up passengers both in Tempe and Pittsburgh.
Uber, originally quick to announce its decision to “ground” its driverless vehicles after the crash, has since fallen silent. The company has ceased all comment about the accident. An Uber spokesperson told us via email, “What I've shared to date is all we are sharing on our findings.” She referred to Tempe Police Department for any more information on the incident.
So, to understand what really happened, and what — if anything — we can learn from this crash, we turned to the Police Report, provided to us by Detective Lily Duran, Media Relations Unit, at Tempe Police Department.
Next page: Crash diagram
The accident took place on a clear day at dusk, at an intersection of South McClintock Dr. and East Don Carlos Ave.
The collision report’s narrative says:
Vehicle #1 (Honda CRV) was driving northbound in the left lane of S. McClintock Dr. when it failed to yield making a left turn onto E. Don Carlos Ave. and collided with Vehicle #2 (Uber Volvo), which was southbound in Lane 3 of S. McClintock Dr.
After being struck, the Uber Volvo collided with a traffic signal pole, then flipped on its side and collided with Vehicle #3 (Hyundai EST) and Vehicle #4 (Ford Edge), which were stopped in traffic southbound in Lane 2 of S. McClintock Dr.
Looking at an accident photo published in the local news, which showed Uber’s Volvo flipped on its side, as well as damage to the Ford and Hyundai, we had assumed that this was an accident between the Ford and the Uber car, with the Hyundai as collateral damage.
Uber accident scene (Source: Local NBC News)
But it turns out that a fourth car, the Honda CRV not shown in the photo, caused the crash.
Reading the police report, Demler first noted, “This is a classic left-turn accident, where the person making the left is always at fault, no matter what mitigating circumstances may have occurred.”
Mitigating circumstances in this particular case are, however, worth noting.
It’s important to note that “traffic was stopped in the middle and leftmost lanes of southbound McClintock, on both sides of Don Carlos,” he explained. This was confirmed by both the left-turning (Honda CRV) driver and the Uber driver.
“As a result, the Honda CRV driver proceeded to make her left turn from the northbound left turn lane, since she didn’t see any vehicles coming the other way in the rightmost southbound lane,” Demler explained.
Next page: Drivers' statements
According to her statement, while turning in front of the stalled left/middle-lane traffic, she saw the oncoming Uber Volvo in the rightmost lane. She slammed on her brakes, but still collided with the left side of the Volvo.
Meanwhile, according to Uber Volvo driver (his statement below), his vehicle was moving at 38 mph. The Uber driver said in his statement that he saw the traffic light change to yellow as his car entered the intersection. Demler remarked that the Uber Volvo did not brake, “even though the light was yellow!”
The Volvo took a relatively minor driver-side hit, Demler said, and continued through the intersection. But then it was out of control and it took out the traffic signal pole on the opposite side of Don Carlos.
As the police narrative shows, “After it hit the pole on its passenger side, the Volvo bounced off, spun & flipped over, hitting vehicles #3 and #4, which were stopped in traffic in the middle lane.” That, Demler said, “explains the curious damage we saw in the photos.”
Demler summed up: “To clarify — the Uber Volvo proceeded through the intersection after being hit on its driver side by the left-turning Honda CRV. This is documented in the police report drawing, which shows the Volvo’s trajectory after the collision. The CRV stopped there. As the CRV driver said, she was in the intersection waiting to make her left turn, so wasn’t moving very fast when she came across the stalled left and middle lanes, and then hit the Volvo moving at a much higher speed through the rightmost lane. Had the CRV been traveling at a higher speed, it is unlikely the Volvo could have proceeded South on McClintock on a trajectory that resulted in it colliding sideways with the light pole on the opposite street corner.”
In the statement, the Uber Volvo driver said there was a blind spot due to the stalled traffic in the other lanes. Demler said, “He was moving too fast to know if there was a vehicle preparing to turn left, but the self-driving system should have been looking out for that.”
In his opinion, “A V2X/V2V system could have provided that information. I think the roof-mounted lidar should have picked up the Honda CRV before the collision, and immediately applied the brakes. But it’s not clear that happened.”
Next page: Questions for Uber
The blame is squarely on the left-turning Honda CRV driver who hit the Uber car. Demler said, “Legally, I understand that the CRV ‘failed to yield.’”
Fault or no fault, however, the Honda CRV driver “actually took more action to avoid the collision than did the Uber in self-driving mode,” Demler believes.
“It is totally careless and stupid to proceed at 38 mph through a blind intersection. The Volvo’s self-driving system failed to execute proper and safe driving behavior,” he added. “We’ve all been there, but any human would know better. You have to watch for traffic coming through the intersection that isn’t visible as you approach. I do that every single time I proceed through an intersection.”
Questions for Uber
So, here are some fresh questions for Uber, after having read the police report. First, how did respective sensors installed in the automated vehicle function at the time of the collision? Did the lidar see the Honda CRV?
In his opinion, “This is in some ways reminiscent of the Tesla fatality.” Demler said, “The Volvo’s roof-mounted lidar should have been able to see the CRV, though its radar and cameras may have been blocked by the stalled traffic on its left. It may have been traveling at too high a speed to properly react in time. The Volvo’s mapping/location software should have known there’s a left turn lane on both northbound and southbound McClintock at Don Carlos, so any vehicle in that lane intends to turn left.”
The second questions, why did Uber Volvo take no action at the intersection?
Demler would like to ask Uber, “Why did your vehicle proceed through the intersection at 38 mph when you could see that traffic had come to a complete stop in the middle and leftmost lanes? What action did the Volvo’s self-driving system take once it recognized a collision was imminent… or didn’t it recognize it at all? Did the Volvo brake after the collision? That would have been the proper procedure, since the CRV had screeched to a halt, and traffic ahead was stopped.”
Uber isn’t talking.
— Junko Yoshida, Chief International Correspondent, EE Times