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Comment by patcheudor | Hacker News Reader

I'd be interested to hear how the radar handles other radar signals. Given the use of police radar, radar detectors, and radar based collision avoidance like what's found in the rear tail-lights of some Ford F150's and of course are used on a fair number of Audi's it would seem the environment could get noisy at times. Yes, the Tesla radar could operate at a specific frequency that would minimize interference, but what happens when a bad actor decides to intentionally "blind" that radar signal? I assume given this is a life critical system that it would have countermeasures, perhaps utilizing a LIDAR or camera based backup?

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I don't know how this particular radar system works, but in general you can modulate radar signals with a special encoding, so that only the sender can receive and interpret it. For all others the signal is juse noise. At university we worked with m-sequence based radar systems that have these properties. This would minimize the possibility that someone (accidently or not) can send signals that you misinterpret. Depending on the remaining possibility you might still want to take same countermeasures.

I think this is where the industry really needs to start internalizing a few rules. As an example, never trust encoding alone to provide integrity for signals tied to life critical systems. This is more true than ever, especially since it's possible to buy software defined radio solutions which work in radar bands:

http://ancortek.com/

Yes, but if you flood it with white noise, it'd screw up any transmit waveforms. The only alternative is to have a software radio that is flexible enough to switch bands when it encounters noise.

In terms of the SDR stuff, I'm thinking more about it being in the hands of a threat actor. One of the things that Tesla nor Google have had to contend with to date in their trials are intentional disruption and subversion of their systems and I only hope they've hired security engineers to consider more than just IT stack vulnerabilities like those explored by Charlie Miller & Chris Valasek (https://www.youtube.com/watch?v=OobLb1McxnI). A great number of jobs are at risk from this technology from long haul truck drivers to bus and cab drivers. This will certainly result in tensions which could result in threat actors going after sensing systems. Readily available radar frequency SDR in those conditions really could be used for harm.

Analogous to shining a flashlight in a driver's eyes or pointing a laser at an airplane cockpit. The law handles it.

well, that doesn't help you if you're dead. although it's probably an argument in favor of not requiring such countermeasures, they would still be nice to have, wouldn't they? :)

That's what I'm afraid of. Rarely is the correct answer to a technological threat vector these days "let the law handle it." In this case it's even worse because of the real world problems that can and do happen when it comes to radio systems combined with the implementation of a life critical system. Look at the Evanston key fob incident as just one example. Would a shop owner with a bad neon sign transformer (or to interfere with radar, a microwave) from China be held liable for accidents on the street?

http://evanstonnow.com/story/public-safety/bill-smith/2016-0...

i think that question is not so pressing until the system is declared fully autonomous as in, no human required anymore to drive. as long as it's just an assistant, the human is supposed to brake. but, since they surely want autopilot to become an actual autopilot...

you could do the same with "normal" cameras (and probably lidar as well) i guess by pointing a laserpointer at it. the safest option is probably to just brake.

here elon musk says they don't use lidar: https://techcrunch.com/2016/09/11/tesla-autopilot-8-0-uses-r...

(as an aside, some years ago we had incidents in the news where people pointed laserpointers at aircraft pilots while landing. the pilot's appropriate response is usually to abort the landing and do a go-around, because that's the safest thing to do in this situation)

I wrestle with this one and am afraid that at the point a car is driving itself, a EULA that the driver agrees to which states: "I will always maintain concentration and control of the vehicle in the case things go wrong" isn't accounting for how the human brain actually works. Humans only make for good backup systems when they are engaged and/or have time to react. I'll give Elon some credit. This is one heck of an experiment with a life critical system.

Emergency braking, as with a blown tire.

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