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New world record with an electric racing car: From 0 to 100 in 0.956 seconds

ethz.ch

221–230 of 307 posts

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#221
post #184

One of the photos really brought something home to me. Where I would expect to see an axle or something to provide torque to wheels from the engine, there is just a yellow wire. I know that's how electric cars work. But something about it in the racing car context just brings it home to me - electricity just works differently to all our other intuitions about the world. Factories used to have bands and axels taking p…

Yeah, they've taken the "distribute mechanical work" part out of the process. It's amazing that all those car cylinders going up and down (or technically, being forced up and down by tiny explosions) are transformed into work. Rotary motion -> work has been part of humanity for a long time. I suppose in our space-bound future it won't be a big factor

Except as artificial gravity or pumps or geared robotic arms or automatic doors or … I think we’ll have rotary motion for some time to come.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#222
post #68

Impressive but for reference, about half the acceleration of a Top Fuel dragster, which are also still getting faster. Here's Brittany Force who holds the current records (fastest time, fastest speed): https://www.nhra.com/news/2022/brittany-force-sets-national-... 0 to 338.43 mph in 3.665 seconds over 1000 feet. (The cars got too fast for 1,320 feet and have been racing 1000 feet since 2008.)

I wanna know how they fare when the vehicle has to do 10 races on the same power train. I bet it would be a lot closer.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#223
post #4

The impressive thing to me is the level of traction needed to do something like this. It seems they're taking old tricks and building a "sucker car". https://www.roadandtrack.com/motorsports/a32350/jim-hall-cha... Still neat stuff. Race sanctioning bodies will need to update their rules or these will just be one off bragging rights.

In Micromouse ( https://en.wikipedia.org/wiki/Micromouse ) - a competition where autonomous devices solve a mouse maze - the fastest competitors are all using fans to increase traction (and thus speed).

Gordon Murray was ahead of his time: https://en.m.wikipedia.org/wiki/Brabham_BT46

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#224
post #141

Earlier quoted context omitted.

> Factories used to have bands and axels taking power from one central steam engine to all corners of the building. From my own experience: a popular home woodworker tool from the middle of the 20th century is a Shop Smith. It had a motor that you would couple to the various mounted attachments to run the lathe or the band saw or the table saw etc one tool at a time. I guess part of the appeal was certainly the size…

Tractors, still widely used today, as essentially a mobile version of this. One of the main purposes of a tractor, compared to other farm vehicles, is that it has a power take-off [0] to enable the engine to drive other farm implements like combines. [0]: https://en.wikipedia.org/wiki/Power_take-off

Easily one of the most dangerous bit of farm equipment. I’ve seen several people killed by getting their hand/arm in a PTO shaft.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#225
I have watched a lot of car acceleration tests on YouTube (thanks COVID)... and the electric vehicles, especially the ones with artificial (vacuum) downforce) are approaching what seem like impossible limits.

For the lesser trained drivers, the acceleration forces experienced appear to temporarily affect some basic functions (like speaking).

However, these perhaps pale in comparison to the repeated acceleration and deceleration tests experienced by John Stapp - https://en.wikipedia.org/wiki/John_Stapp

I cannot find information about his 1-second speed (trap) number, but the Wikipedia article notes that on

"3 January 1955 says he accelerated to 632 mph (1,017 km/h) in five seconds and 2,800 feet (850 m), then coasted for half a second, then slowed to a stop in 1.4 seconds. It says the track was 3,500 feet (1,100 m) long."

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#226

Earlier quoted context omitted.

Tractors, still widely used today, as essentially a mobile version of this. One of the main purposes of a tractor, compared to other farm vehicles, is that it has a power take-off [0] to enable the engine to drive other farm implements like combines. [0]: https://en.wikipedia.org/wiki/Power_take-off

Easily one of the most dangerous bit of farm equipment. I’ve seen several people killed by getting their hand/arm in a PTO shaft.

You might be the only person on the planet who's witnessed several of those, if you mean first-hand.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#227

One of the photos really brought something home to me. Where I would expect to see an axle or something to provide torque to wheels from the engine, there is just a yellow wire. I know that's how electric cars work. But something about it in the racing car context just brings it home to me - electricity just works differently to all our other intuitions about the world. Factories used to have bands and axels taking p…

The "instant" torque provided by electric motors compared to traditional IC/drivetrain systems is really sexy, but what is perhaps more useful is the vastly quicker power modulation that is possible with electric systems.

Electric cars can manage traction control so much more precisely that they can do seemingly impossible things. This snow climb comparison between various Audis - IC and electric, demonstrated that electric traction control could easily manage low friction scenarios which seem unimaginable. https://www.youtube.com/watch?v=HJRRvHlvhAI

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#228
post #31

> "To ensure strong traction right from the start, the AMZ team has developed a kind of vacuum cleaner that holds the vehicle down to the ground by suction." Traction is now the limiting factor, so better acceleration results will be driven (hah) by better traction.

A similar thing was done in F1 in 1978: https://en.wikipedia.org/wiki/Brabham_BT46 It was swiftly banned of course, since it worked too well.

Or not well enough?

These cars would appear to be utterly dependent on maintaining a very specific distance from the track for the ability to stay grounded. You imagine going into a curve at high speed and the slightest body roll or debris on the track that might kick the car up an inch or so would break the suction and send the car flipping like a pancake.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#229
post #189

Earlier quoted context omitted.

I use calculators plenty, but I neither have that one installed nor use it. On my PC, I use either grpn or units. More often, I pull out my HP 48G+.

GRPN for anyone else who doesn't know it: http://lashwhip.com/grpn.html What I meant to say is that, if one uses a featureful calculator like qalc, then you get unit conversion included without needing two separate utilities. Of course, if you've used a(n obscure) calculator for decades then it may be easier to learn to use a separate unit convertor instead

I wouldn't exactly call the HP "obscure", but it does support unit calculations too. And "units" is more than plenty when I want infix operations.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#230

I think hub motors like this are the future. Frees up space under the car for more battery. Removes the complexity of drive shafts and universal joints. Gives software full traction control. Reduces design time for new vehicles (just route a power and data cable to a wheel and you have a vehicle). Is the first step to all-electric braking. The downside is more unsprung mass. But modern motors are getting lighter and…

I wonder if centrifugal forces are useful for anything. For example, would there be any benefit in pressing battery cell plates closer together?
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