Automatic braking systems save lives. Now they’ll need to work at 62 MPH

>>The systems “are headed the right way,” says Greg Brannon, the director of automotive research at AAA.

They may have some promising data, but from what I've seen driving 2019 and 2021 model vehicles from Ford and Mazda, they are not even close to ready for prime-time.

I find both vehicles consistently falsely trigger the red-flashing-and-loud-beeping "COLLISION ALERT!!" dashboard warning to both small pavement cracks/potholes, and also to vehicles parked on the outside of a curve. This has happened at least a dozen times in the past ~30,000 miles driven. If those were instead automatic braking events, they would have caused an unnecessary rear-end accident least three times, as if I'd surprise "brake-checked" the driver behind me.

Yet, in an ACTUAL near-collision situation a few weeks ago, driving at night ~50mph on a rural road, a car ran a red light right in front of me, and I had to full-on threshold brake, years of road-race training reflexes kicking in before I was even aware of it. I barely avoided a collision, stopping with smoking brakes and a passenger with a pulled back muscle from having been not quite square with the seatbelt, my front bumper about a meter from their driver's door.

The car never made a peep — it completely missed the incident.

Of course, a working automatic braking system might have helped anyone in that situation, including me if I'd been a bit more sleepy or distracted. BUT IT DID NOT EVEN DETECT IT. The track record for the past 30,000+ miles is:

— 100% false positives — 100% false negatives

These 'collision detection systems' are 2-5 years newer than the systems AAA tested, yet the track record is awful. IDK what they are smoking but I do not want any.

I doubt the automakers are somehow holding back some magic solution, and would give them a LOT more time to get it right.

Just because a technology is promising does not mean it is ready to provide a benefit released in the wild on fast-moving multi-ton vehicles.

Smoking brakes from a single emergency stop? Sounds like your car is defective and I'd get it checked out. Sounds like you were lucky this time and avoided the accident but get your brake pads changed and make sure the fluid is topped up as that isn't right. Potential issues are stuck calipers, worn out friction material, or boiling fluid.

With a well maintained car (i.e. brakes that don't end up smoking when doing just a single emergency stop, even from 60-80mph...) you are less likely to avoid accidents by just a meter...

It's a metaphor; I didn't actually smell any smoke (but didn't stay around either). But I guarantee those pads were momentarily very hot.

Thanks for your concern, but no, the car's braking capability was fully up to snuff and not compromised, stuck, worn-out, or boiling; it hauled the car down to zero in a handful of car-lengths, and mildly injured the passenger — crappy brakes can't do that.

And yes, perfectly good brakes, even race brakes, can be made to smoke in a single stop. It's done every time you take them out to bed them after install (many high-performance brake pads are 'transfer pads' that work best when some of their material is transferred at temperature to the rotor). Also, it is very common to see high-performance situations where the rotors are glowing-hot in a corner [0].

The reason it is so rare in ordinary street cars is most people not knowing how to use even 30% of the real braking capability. People either don't press hard enough, or just press mash the pedal and skid. Once the tire is skidding, the brakes aren't turning, so they aren't heating. Even ABS just splits the braking between the pads and the intermittently skidding tire.

Threshold braking is a skill that both takes time to learn and practice to maintain. It is basically getting a feel for the exact maximum braking grip the tire has at that moment, and braking just below that threshold. It extracts maximum performance from the car (sliding friction is always less than gripping friction) and also puts maximum heat into the pads.

And yes, threshold braking can really heat up the pads in one stop, and (depending on the car, track, and driver) completely burn down a set of pads in a single outing. OTOH, I had a set of pads last an entire race season on one car, or have to replace them every several sessions with other cars. Properly used, brake pads are just a wear item, but this is unfamiliar with street use, because you should typically almost never be threshold braking, so they'll last tens of thousands of miles.

But the main point here is that the ONE situation I've had in the last 30k miles with "collision alarms", the car completely missed it.

[0] https://www.youtube.com/watch?v=NBoMTYZAyJc

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