Autonomous DeLorean drives sideways to move forward • Hacker News Board

Re: Autonomous DeLorean drives sideways to move forward

#121

Post by sudosysgen » Sun, Dec 22, 2019, 3:32 PM UTC

fieldmeasure wrote: post #76

Don't get me wrong I think this is an impressive feat and I am always impressed to see universities pull off these kinds of complex system and control projects. Yet, there are a few things that I would like to mention. The article says that the car does "doughnuts with inhuman precision" and they want to develop vehicles that can handle "emergency maneuvers or slippery surfaces like ice or snow". In this context, I f…

Inch precision localization isn't out of the grasp of human drivers. Kimi Raikkonen at Monaco coming millimetetd from the walls repeatedly comes to mind.

It also isn't out of the abilities of a bog standard optical SLAM+IMU.

Re: Autonomous DeLorean drives sideways to move forward

#122

Post by RandomBacon » Sun, Dec 22, 2019, 3:47 PM UTC

charliepark wrote: post #39

Animats wrote: post #6

They did most of that back in 2015.[1] This is version 2. It's interesting what's happening as the control theory people get into machine learning. The controls people don't typically run a neural net as a controller. They use the trained net as a tool for building a controller with known continuity properties. The trouble with pure neural net controllers is that they sometimes do something totally bogus for some dat…

> "The trouble with pure neural net controllers is that they sometimes do something totally bogus for some data point within the normal input space." A friend's theory on Google Maps is that it sometimes intentionally sends you down a non-optimal path in order to gather data on alternate routes. This friend isn't in the ML space, so this is just their anecdotal observation. Are they right, then?

That is my theory as well.

It sometimes suggests a route I don't normally take, then when I continue on the route I normally take, the ETA updates to say I will now arrive sooner.

Google Maps intentionally suggests to take longer routes.

Re: Autonomous DeLorean drives sideways to move forward

#123

Post by marcosdumay » Sun, Dec 22, 2019, 3:50 PM UTC

allovernow wrote: post #43

Animats wrote: post #6

They did most of that back in 2015.[1] This is version 2. It's interesting what's happening as the control theory people get into machine learning. The controls people don't typically run a neural net as a controller. They use the trained net as a tool for building a controller with known continuity properties. The trouble with pure neural net controllers is that they sometimes do something totally bogus for some dat…

>The trouble with pure neural net controllers is that they sometimes do something totally bogus for some data point within the normal input space. That's not OK in control systems. Is that actually true? Everything we do at work with neural nets seems to indicate continuity. We do stuff with mathematical simulations and imagelike processing. Latent space for auto encoders tend to be smoothly varying throughout the ra…

> I thought the problem is just that it isn't proven that neural nets are sufficiently smooth.

I think this is exactly what the GP was trying to say (at least, this is what I understand from it). The continuity bit is about the (non ML) controller, not about the neural network.

Nearly all neural networks generate continuous output. They do interpolate between their learned points. The problem is that it is very hard to verify (and impossible to predict) the interpolation function, so it may cross outside of the safety area on any point.

Re: Autonomous DeLorean drives sideways to move forward

#124

Post by toss1 » Sun, Dec 22, 2019, 3:51 PM UTC

devit wrote: post #103

Doesn't this sort of movement cause a lot of wear on the tires, thus making it unsuitable for routine use?

Yes, but.

Yes #1 is that this is mostly Drifting techniques, which are mostly for show/style competition. The tyre slip angles mentioned are around 40deg, far past the optimal level of grip.

Yes #2 Racing techniques are more explicitly seeking to optimize for maximum grip, often found around 3 to 6 degree slip angles (depending on tyres, tyre pressure, tread & road temps, road cleanliness, dryness, etc.).

Both still are in the ranges of tyre slippage, at the edges of control, and burn tyres at crazy rates vs street use (drifting just insanely so).

Moreover, as someone with race training & experience, I can say that anyone doing full race/drift techniques on the streets as an ordinary practice is a real a*hole & a hazard.

BUT, all that said, it is absolutely critical to have thise techniques in your bag of tricks, available to use when something exceptional happens. In those rare-ish events, being able to use the full performance envelope of the vehicle is a real life saver, both for you and the others nearby.

So, for sure not every day, but these guys are absolutely right about the need to work on the full dynamic range of the performance spectrum.

Re: Autonomous DeLorean drives sideways to move forward

#125

Post by chkaloon » Sun, Dec 22, 2019, 3:51 PM UTC

Back in the late 70s, my high school driving instructor said "don't tell your parents, but the best way to learn how to control a car is to go out to the school parking lot on a snowy night and spin donuts." Funny that they are finding that artificial intelligence can use the same method.

Re: Autonomous DeLorean drives sideways to move forward

#126

Post by jacquesm » Sun, Dec 22, 2019, 3:56 PM UTC

bborud wrote: post #90

OnlineGladiator wrote: post #62

Earlier quoted context omitted.

I don't think this is true. If you hit black ice and the tire skids, the problem is you just have no friction. Modern traction control systems already account for this as best they can - I don't see how this model would help any more except for trying to go faster through patches of black ice. And even then, drifting inherently requires traction in order to modulate the throttle and control the vehicle. If you can't…

If you hit black ice you are screwed anyway. The most useful thing your car could do is to detect black ice before you hit it. I’ve seen some technologies for doing just that. Black ice isn’t very easy to distinguish from other surface conditions cheaply, but the technology exists. (It just has to reach volume production).

The very best way to deal with black ice is to avoid it entirely, simply do not drive if the conditions susceptible to generating it are present.

Re: Autonomous DeLorean drives sideways to move forward

#127

Post by mannykannot » Sun, Dec 22, 2019, 4:00 PM UTC

wongarsu wrote: post #113

krallja wrote: post #107

Earlier quoted context omitted.

Google Maps is not just path finding; it also takes real-time traffic info into account.

Which is still just path finding: estimate travel time for each segment, use travel time instead of distance as edge cost. Don't take that as a dismissal of Google maps: it's the most impressive path finder I know, working with high performance over long distances, taking into account real time information, and calculating meaningful alternative routes to choose from. It's an impressive piece of technology that actua…

Compared to distance, travel time is a more complex and nuanced variable. There are more things that a route planner could do, and I suspect that Google maps (and others) are doing some of them. They include taking into account the variance in the time to transit each route segment (which might be, for example, weather-dependent), preferring simpler routes (including taking account of statistics on missed turns), and taking into account the effect of its -- and others' -- recommendations on the flow of traffic (or even on public safety.)

Re: Autonomous DeLorean drives sideways to move forward

#128

Post by maxerickson » Sun, Dec 22, 2019, 4:02 PM UTC

jamestimmins wrote: post #9

So is the general idea that by removing the automated controls, which normally limit drift so human drivers don't lose control, they're able to gather data at the extremes of car handling? I'm curious how this would be applied in the real world. It almost seemed to suggest that a self-driving car would operate with those stability controls turned off, allowing it operate evasive maneuvers that would be impossible in…

It's a demonstration that they can predict the result of a wide range of control inputs across a wide range of vehicle states.

There's nothing unusual about a car without stability control. ABS and traction control have only become standard features relatively recently. Vehicle stability control builds on traction control by attempting to predict the driver's intent instead of just preventing slipping.

I think that you are right, that it enable more drastic responses in situations that required them. The normal control mode would probably focus on passenger comfort though.

Re: Autonomous DeLorean drives sideways to move forward

#129

Post by zzzeek » Sun, Dec 22, 2019, 4:43 PM UTC

they have gotten this car to do complex and exotic movements via automated manipulations of the car's human-oriented interface, that is, a single steering wheel, four wheels that turn in the same direction, and then the brakes / accelerator.

It seems though that if you are actually trying to design autonomous cars that feature greater maneuverability than what is normally possible you'd instead ditch the whole assumption of a single steering column and all of that and just consider all the wheels as independent, or maybe add more wheels that engage for some kinds of maneuvers, or probably a whole lot of other things that im sure all the car people here know are possible if you are no longer constrained to controls created for a single human with only four limbs and extremely limited coordination and reaction time.

Re: Autonomous DeLorean drives sideways to move forward

#130

Post by zzzeek » Sun, Dec 22, 2019, 4:49 PM UTC

toss1 wrote: post #124

devit wrote: post #103

Doesn't this sort of movement cause a lot of wear on the tires, thus making it unsuitable for routine use?

Yes, but. Yes #1 is that this is mostly Drifting techniques, which are mostly for show/style competition. The tyre slip angles mentioned are around 40deg, far past the optimal level of grip. Yes #2 Racing techniques are more explicitly seeking to optimize for maximum grip, often found around 3 to 6 degree slip angles (depending on tyres, tyre pressure, tread & road temps, road cleanliness, dryness, etc.). Both still…

> BUT, all that said, it is absolutely critical to have thise techniques in your bag of tricks, available to use when something exceptional happens. In those rare-ish events, being able to use the full performance envelope of the vehicle is a real life saver, both for you and the others nearby.

are you referring to during a road race, or ordinary driving on ordinary streets? It would be great if you could try to provide evidence for the latter. I've never heard of accidents being avoided on highways because someone knew how to do racecar drifting. My own 30 years of driving experience would suggest that not tailgating, keeping a safe distance from the other cars, and being alert for those occasional race-car-wannabes whipping in between everyone, invariably always driving BMWs, is likely to be statistically much more effective.