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The examples where this happens have always seemed fairly weak to me. How many of the grave errors, not just where it's the wrong type of animal or container but actually thinking it's radically different, survive an application of Gaussian blur? Furthermore self-driving cars are a combination of signals; you are going to need to simultaneously fool both LIDAR and cameras.

On top of that you are going need to fool them over multiple frames, while the sensors get a different angle on the subject as the car moves. For example in the first Deep Q-learning paper, "Playing Atari with Deep Reinforcement Learning"[0], they use four frames in sequence. That was at the end of 2013.

I don't think anyone will be able to come up with a serious example that fools multiple sensors over multiple frame as the sensors are moving. Even if they do then inducing an unnecessary emergency stopping situation is still not the same as getting the car to drive into a group of people. Even if fooled in some circumstances the cars will still be safer than most human drivers and still have a massive utilitarian moral case in relation to human deaths, on top of the economic case, to be used.

The fooling of networks is still an interesting thing, but it's been overplayed to my mind and is not particularly more interesting than someone being fooled for a split second into thinking a hat stand with a coat and hat on it is a person when they first see it out of the corner of their eye.

[0]http://arxiv.org/pdf/1312.5602.pdf page 5



1. Gaussian blur is just a spatial convolution (recall from signal processing). If a network is susceptible to adversarial examples, it will still be susceptible after a Gaussian blur (assuming the adversary knows you're applying a Gaussian blur. If the adversary doesn't, that's just security by obscurity, and they'll find out eventually).

2. A sequence of frames does not solve the issue because you can have a sequence of adversarial examples (although it would certainly make the actual physical process of projecting onto the camera more difficult, but not really any more difficult than the original problem of projecting an image onto a camera).

3. Using something conventional like LIDAR as a backup is the right approach IMO, and I totally agree with you there. But Tesla and lots of other companies aren't doing that because it's too expensive.


1. If that's the case perhaps another kind of blurring? "Intriguing properties of neural networks" (https://arxiv.org/pdf/1312.6199.pdf page 6) has examples where you get radically different classifications that I don't think would occur naturally or survive a blur with some random element, let alone two moving cameras and a sequence of images. As the title says it's an intriguing property, not necessarily a huge problem.

2. I honestly can't think of a situation where this could occur. It's the equivalent of kids shining lasers into the eyes of airline pilots, but the kids need a PhD in deep learning and specialised equipment to be able to do it. A hacker doing some update to the software via a network sounds much more plausible than attacking the system through its vision while it's traveling.

3. This is the real point in the end I guess, this Google presentation (https://www.youtube.com/watch?v=tiwVMrTLUWg) shows that the first autonomous cars to be sold will be very sophisticated with multiple systems and a lot of traditional software engineering. Hopefully LIDAR costs will come down.


1. Those are examples for a network that does not use blurring. You have the be careful because, remember, the adversary can tailor their examples to whatever preprocessing you use. So the adversarial examples for a network with blurring would look completely different, but they would still exist. Randomness could just force the adversary to use a distribution over examples, and it could mean they are still able to fool you half the time instead of all the time. However, I wouldn't trust my intuition here: that is really a question for the machine learning theory researchers (whether there is some random scheme that is provably resilient or if they're all provably vulnerable, or proving some error bounds on resilience, etc.).

2. The problem of projecting an image onto a car's camera already implies you'd be able to do it for a few seconds.


"It unlikely to happen" is not a good strategy to rely on with systems operating at scale. There are about a billion cars on earth traveling trillions of miles every year, many of which will eventually be self-driving. At that scale, you don't need a malicious actor working to fool these systems, you just need to encounter the wrong environment. And even if the system is perfect on the day it's released, that doesn't mean that it will remain so indefinitely (even with proper maintenance).

Studying induced failure in neural networks may help us understand the failure modes and mechanisms of these systems.




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