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Autonomous DeLorean drives sideways to move forward

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Re: Autonomous DeLorean drives sideways to move forward

#191

Post by Jamwinner »

bborud wrote: post #93
taneq wrote: post #84

"This leads to the physically insightful result that one can use the rotation rate of the vehicle's velocity vector to track the path, while simultaneously using the yaw acceleration to stabilize sideslip." This sounds like what every racer will tell you: When the car is sliding, you control your direction with the throttle and control the angle of the slide with the steering.

it’s generally a bit more complicated than that.

Not really. The hard parts are initiating the slide and recovering from it, in the correct trajectory. The actual slide can be done with a rope and a 2x4.

Re: Autonomous DeLorean drives sideways to move forward

#192

Post by Jamwinner »

taneq wrote: post #85
sudhirj wrote: post #31

Earlier quoted context omitted.

ABS is a very human-centric system the tries to keep the car controllable under low traction, often by sacrificing something aspect of movement. The neural nets here throw all that out of the window, and control the car with direct physics, without being once or twice removed from reality. The video also has some very interesting points about how the AI should be able to control the acceleration and braking on each w…

This was what finally killed my long-held attitude of "we don't need no stinkin' ABS". No matter how good I am, I will never be able to independently limit-brake each wheel of my car.

Yet, in snow, non-abs cars still stop faster. Hmmm.

Re: Autonomous DeLorean drives sideways to move forward

#193

Post by ehnto »

fourthark wrote: post #164
ehnto wrote: post #114

Earlier quoted context omitted.

Which is very common, even in controlled drift events. Over the course of a single run, tires can completely change grip coefficients.

So you got the sense that it was recalculating based on the response it got? I wasn’t clear on that from the article.

I combed through the article and a previous article linked in it, but I can't find any concrete answer one way or the other. My intuition is that it would have to be recalculating it's inputs as the environmental variables change. They could have modeled in expected tire friction coefficient changes, or perhaps the task is more forgiving of that changing variable than I expected.

One of their stated goals is to drift in tandem with another human driven vehicle though, so they are likely aiming for complete, adaptable autonomy.

Re: Autonomous DeLorean drives sideways to move forward

#194

Post by aeternum »

Ericson2314 wrote: post #167
aeternum wrote: post #151

Earlier quoted context omitted.

It could be that Google Maps is saving everyone time by doing this. The Braess Paradox is really interesting, and this could be an attempt to prevent it: http://vcp.med.harvard.edu/braess-paradox.html

I would imagine introducing cars to a road itself causes a braess paradox.

Introducing cars does cause more traffic.

However the interesting thing about braess paradox is that even if you keep the number of cars constant, introducing a new road can make travel times worse.

Re: Autonomous DeLorean drives sideways to move forward

#195

Post by taneq »

Jamwinner wrote: post #192
taneq wrote: post #85

Earlier quoted context omitted.

This was what finally killed my long-held attitude of "we don't need no stinkin' ABS". No matter how good I am, I will never be able to independently limit-brake each wheel of my car.

Yet, in snow, non-abs cars still stop faster. Hmmm.

Same on gravel, and for the same reason. Neither of those are something I run into particularly often, though. Painted lines on wet roads that will cause the wheels on one side to lock up, though...

Re: Autonomous DeLorean drives sideways to move forward

#197

Post by bborud »

Jamwinner wrote: post #191
bborud wrote: post #93

Earlier quoted context omitted.

it’s generally a bit more complicated than that.

Not really. The hard parts are initiating the slide and recovering from it, in the correct trajectory. The actual slide can be done with a rope and a 2x4.

Most cars sold in Europe these days are FWD.
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