every time you get in your car, a web of computers, cameras, sensors, and more is working to make you a better driver. That's blind spot monitor saying like, Hey, there's people to your left. This web powers driver assist, a system that lets your car think and sometimes drive on its own. It's truly like you're driving a supercomputer at all times. But as the tech advances, there are questions about whether these automated backseat drivers are actually safe, especially as more cars hit the road without hands on the wheel. This is the tech behind driver assist. I'm not going to do anything, and then it should automatically apply brakes if this car sees a pedestrian before you do. It can hit the brakes on its own. It's a pretty abrupt stop. The Insurance Institute for Highway Safety says that technology like this can reduce rear-end crashes by about 50%, and it's just one of a suite of features that make up driver assist. The vehicle may automatically apply the brakes to prevent a crash, or it may, you know, tug the steering wheel to get you back in

your lane, and so anything that's actively helping the driver is sort of a driver assist feature. To get a closer look at the technology that allows a car to do this, the journal visited the Toyota and Lexus headquarters in Texas. If I were to take out this entire Dash, you would see hundreds, if not thousands, of wires. These wires connect dozens, sometimes hundreds, of computers throughout the car. If we just had radar, but your foot was physically attached to the throttle and it wasn't electronically controlled, we wouldn't be able to stop that as a car. So, just by having one system alone without being able to have the conversation, it's really not. It's just an empty data set. Some control specific functions like the temperature or the throttle on your engine. Others have complex chips that process data from the core Tech that makes driver assist possible, an array of cameras and sensors around the car that allow it to see. The main camera is here. It's going to be a single lens camera up there that's doing multiple fields of view, so it's going to

be scanning out far as well as short. Some cars also have cameras at the back and under the mirrors. These cameras connect to chips that are trained to quickly recognize objects like lanes, cones, and cars. But many cars don't operate on cameras alone. Obviously, there are limitations. Weather can cause problems, low light. That's why many cars also have a variety of sensors. These sonar or ultrasonic and radar sensors send out sound or radio waves. So, as those bounce off, those return to them, and it's able to tell you distance from objects. Then all of that data needs to be communicated back to the car. That radar sensor sends its signal through its wires all the way up underneath the fender into the dash, starts talking to its computers. So, then from inside the vehicle under the dash goes back out here. The request to slow down goes to the engine ECU. So, if you were using cruise control, for example, it sees that we're kind of approaching this vehicle. The radar system knows that that is a very large object in front of us.

and it is constantly calculating the distance between us and that. But while all of that is watching what's happening outside of your car, there's tech watching the inside too. Most cars made in the last decade use a sensor in the steering wheel to make sure drivers have their hands on it. But it knows that my hands are here. If I just touch the sides of it, it understands that there's being a torque applied to it. I am not steering it at all, but it's going to once again start to see how it's pulling me back into my lane. There's no audible alert, and now it's saying, Hey, you're not touching the steering wheel. So, it says Lane Departure Alert. But many cars are also starting to incorporate this. This is called a driver monitor camera. It's a couple of little laser arrays that are constantly looking for the attentiveness of my eyeballs. These systems work together to make sure a driver has their attention on the road. If not, and it's letting me know, and then it's going to

be pulling me back into the lane, but this monitoring can be one of the hardest pieces of driver assist tech to get right. Many of the vehicles will let you drive, um, you know, much longer than we think is comfortable without knowing if the driver is engaged, and one that many automakers are tackling as they move to the next step of driver assistance tech, true hands-free driving. Advanced Drive activated. I have my hands kind of near the steering wheel on my knees. I have both my feet flat on the floor, and it's handling all of this Dallas traffic. This is one of Lexus's higher-end vehicles that does hands-free driving, a system the company calls Teammate. It only has a couple of additions, one being more computing power to process additional cameras and analyze map data. Another big difference is this, an additional sensor called LIDAR. It's essentially a laser array, so it's kind of shooting out lasers. Having a laser array like a LIDAR sensor, uh, being able to judge distance, uh, will be exponentially faster than waiting for a

radar signal to come bouncing back, but LAR is expensive and is usually only available on higher-end models. But even though these systems are on the market now, they have a long way to go. The IHS recently conducted its first test of partially automated systems. Teammate was the only hands-free system tested that earned an acceptable rating; none of them earned a good. Some of the manufacturers are not monitoring the driver well. There are a couple that you don't have to be buckled up to go into partial automation. So, depending on the manufacturer, there are pieces missing in order for them to get our good rating. While the IIHS recommends cars with automated safety features right now, the agency doesn't see any benefit from automation focused on convenience, like hands-free driving. We're concerned that drivers will become over-reliant on them. Even if a system works well most of the time, the driver may not be prepared to take over in an emergency situation. Regulators have investigated hands-free systems from Tesla and Ford after fatal crashes, and while driverless cars are

Hitting the road in some cities, your car is probably still a long ways off from being able to drive itself everywhere. We're making lots of decisions instantly as we drive. Even the way different states mark the road is very different. All of those have to go into a software version to figure out a self-driving car, and it's very challenging.

How Cruise Control, Crash Prevention and Other Driver Assist Tech Work | WSJ Tech Behind

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How Cruise Control, Crash Prevention and Other Driver Assist Tech Work | WSJ Tech Behind

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