Automatic emergency braking is now a common feature on many cars. It’s intended to slow a vehicle down when the driver may not be aware of a hazard, or is not able to react in time. However, these systems are not infallible, as one recent story out of China demonstrates.
The matter concerns the Li L9, a full-size luxury SUV from Chinese manufacturer Li Auto. Naturally, it’s equipped with all the usual modern safety equipment, including automatic emergency braking. A few months back, the system ended up putting the L9 in the headlines in China—for all the wrong reasons.
As seen in a video shared on Twitter, the L9 was driving at just under 50 mph on the G70 Expressway, when it passed under a billboard ad for vans. As per the footage, the vehicle can be seen to slow quickly, as if the brakes were slammed on—a dangerous maneuver to undertake on a free-flowing highway.
Edge case for vision-based ADAS? A brand-new LI Auto L9 run on ADAS mistakes the vehicle image in the overhead billboard as an actual stationary vehicle in the lane, resulting AEB to kick in, then hit by a vehicle coming from behind. pic.twitter.com/6ZiCbfV0eH
— Ray (@ray4tesla) May 10, 2024
As reported by Pan Daily, the owner claimed this was due to the automatic emergency braking system, which mistook the vans in the advertisement for a real vehicle. Thus, assuming a collision was imminent, it slammed on the brakes. A rear-end collision was reportedly the result, with the owner demanding 20,000 yuan ($2,750 USD) in compensation.
Li Auto eventually confirmed that sequence of events. “The onboard system mistakenly identified an advertisement image as a real vehicle,” stated a company representative speaking to Pan Daily. The company noted that the AEB software would be improved to avoid this problem in future.
This incident happened despite the sophistication of the assisted driving system in the Li Auto L9. It features lidar, radar, and ultrasonic sensors in addition to multiple cameras. Regardless, all that redundancy wasn’t enough in this case.
It’s an amusing problem that thankfully did not have a major negative outcome. Nobody was seriously injured in the crash. However, it’s easy to understand how frustrating this would be for the driver. It’s one thing for a vehicle to crash while under fully autonomous control. It’s another thing entirely for the computer to step in while you’re doing a fine job of driving, only to help precipitate an accident on its own.
It’s not the first time Li Auto’s automatic systems have come under scrutiny. In 2023, Car News China reported on a driver who said their car spotted “ghosts” as it drove past a cemetery. As they drove through the area, the car’s camera appeared to be detecting humans and cyclists when there was nobody around. “This is not a supernatural event, but is caused by the limitations of sensor recognition capabilities on the market,” responded the automaker, noting that it was merely a sensor error.
A LiAuto PHEV owners club decided to attempt the world record for the “longest consecutive rear-end collision.”
It appears to have been a great success. pic.twitter.com/I2yscL8i3F
— ????????China EV, Engineering & Food???????? (@ChinaEV_Eng_Lif) June 17, 2024
Thanks in part to this story, Li Auto has made the news again more recently for another rear-end incident. This past weekend saw a stack of Li Auto vehicles in a chained rear-end crash on a highway in Shantou, Guangdong during an outing of the local Li Auto car club.
In this case, AEB was involved, but not believed to be to blame. The incident was apparently caused when the lead vehicle in the pack stopped for a red light. A following vehicle was driving too fast in the wet and slippery conditions and was unable to stop in time. Automatic emergency braking engaged, but could not prevent the crash from occurring.
When it comes to the billboard incident, though, it’s hard to say what drivers can do to avoid getting caught out. It’s a rare occurrence, to be sure, but also one few of us would expect to deal with. You could drive around with AEB turned off all the time, but then you’d be losing the benefit of the system. At the same time, if you did end up coming to grief because of an automatic safety intervention, you’d be incredibly upset that you’d crashed through no fault of your own.
Ultimately, the solution is better engineering to avoid uncommon but foreseeable cases like these. When it comes to automatic safety systems, automakers have by and large gotten it right. But as they should, the instances where automatic safety systems do not correctly interpret their surroundings will stand out as an unacceptable danger to the driving public.
Image credits: via Twitter screenshot, Li Auto
My Subaru has mild stroke about 75 / 100 times I pull into the garage and a major, brake-slamming stroke about 5% of the time. I’d love to be able to predict what will happen and when…
My Volvo fully stroked out on me backing into my garage today. My kids yelled out “DAD WHAT DID YOU HIT!!”
It’s a very jarring experience when you know you’re in the clear but your car feels otherwise.
This reminds me of the Tumblr post from a South American Tesla owner whose car kept breaking because it mistook the guy sitting on a flatbed truck for a pedestrian. The caption was “I hate my country” with a picture of the offending truck and passenger
That’s a pretty bold statement. Every article about AEB has numerous comments about different makes that have problems with phantom AEB events. I would argue that no automaker has gotten AEB right yet and it’s not clear they will, short of solving the full autonomy problem. After all, if your software is smart enough to accurately determine when it needs to brake it’s probably smart enough to steer and accelerate too.