ShareIt turns out Teslas camera-vision-only approach to self-driving is no match for a Wile E. Coyote-style fake wall. Earlier this week, former NASA engineer and YouTuber Mark Rober posted a video where he tried to see if he could trick a Tesla Model Y using its Autopilot driver-assist function into driving through a Styrofoam wall disguised to look like part of the road in front of it. The Tesla hurls towards the wall at 40 mph and, rather than stopping, plows straight through it, leaving a giant hole.It turns out my Tesla is less Road Runner, more Wile E. Coyote, Rober says as he inspects the damage on the front hood. The video, posted only a couple days ago, had racked up over 20 million views by Wednesday morning.Could Lidar have detected the wall?The stunt draws inspiration from an iconic Looney Tunes skit in the Road Runner Show. In the cartoon, Wile E. Coyote tried to set a trap for Road Runner by painting what looks like a tunnel entrance into the side of a boulder hoping it will stop him dead in his tracks. Road Runner zooms around the corner and passes right through. When he furiously follows in hot pursuit, Wile E. smacks into the fake tunnel opening face first. Alas, another victory for Beep Beep.Rober is convinced the culprit for the crash in his case resides in Autopilots lack of Lidar sensors. Lidar, which stands for Light Detection and Ranging, works by sending out millions of laser pulses in all directions around a vehicle and measuring how quickly they bounce back. That information is used to rapidly create a 3D map of the vehicles surroundings and help it avoid obstacles like pedestrians, animals, orin this casea camouflaged wall. Most people will recognize Lidar as the spinning tops fastened on the roof of driverless vehicles.Though most high-level autonomous vehicle systems on the road today like Waymo use Lidar prominently, Tesla has long bucked that trend in an effort to one day create full autonomy using only camera vision. Elon Musk, the companys CEO, has been outspoken about this approach, repeatedly criticizing Lidar as a crutch and a fools errand. In the video, Rober explains why he believes that so-called crutch could have prevented his Tesla from crashing through the wall. Get the Popular Science newsletter Breakthroughs, discoveries, and DIY tips sent every weekday. By signing up you agree to our Terms of Service and Privacy Policy.While that [the fake wall] sort of looks convincing, the image processing in our brains is advanced enough that we pick up on the minor visual inconsistencies and we wouldnt hit it, Rober said. A car with Lidar would stop because it is using a point cloud that detects a wall without seeing the image at all.To buttress that point, Rober repeated the same test using a Lexus RX-based prototype equipped with Lidar. In that case, the Lexus detected the wall and slowed to a stop before making contact. Rober ran several additional tests, including seeing whether the vehicle would stop for a mannequin standing in the road under both clear conditions and in rain and fog. The Lexus stopped in both scenarios, but the Tesla on Autopilot struggled to detect the mannequin in adverse weather conditions.Related: [Why are driverless cars still hitting things?]Teslas lack of Lidar has draw regulatory scrutinyThough Robers results are pretty funny they point to a real debate raging among autonomous vehicle developersoften with serious consequences. Last year, the National Highway Traffic Safety Administration opened up a new federal investigation into Teslas Full-Self-Driving (FSD) feature, a supposedly more advanced version of Autopilot, following numerous reports of crashes in poor visibility settings. One of those crash reports resulted in the death of a pedestrian. Tesla did not respond to our request for comment.Multiple autonomous driving experts previously speaking with Popular Science did not completely rule out the possibility of autonomous systems driven primarily by camera vision. Still, they pointed to several real-world examplesincluding one where a Tesla on Autopilot plowed through a deer without stoppingas potentially tied to the lack of Lidar.[LiDAR is] going to tell you how quickly that object is moving from space, University of San Francisco Professor and autonomous vehicle expert William Riggs previously told Popular Science. And its not going to estimate it like a camera would do when a Tesla is using FSD.