Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

ethz.ch

Post reply on HN
Print view View original

271–280 of 307 posts

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

#271

Post by The_Double »

namdnay wrote: post #194
londons_explore wrote: post #76

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…

Modern motors get lighter in part because they can offer lower torque with a smaller rotor but compensate with higher rpm. That’s not possible for a hub motor

The hub motors on the car in the OP run at ~24k RPM (faster than any production electric car AFAIK) and have a multistage planetary gearbox for reduction.

Pretty much all top Formula Student cars now use hub motors. Mainly for packaging reasons. Putting the motor in the unused space in the wheel means you can make a smaller chassis and have more space for wings and underbody aero.

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

#272

Post by adfiognionio »

AtlasBarfed wrote: post #202
adfiognionio wrote: post #147

Earlier quoted context omitted.

This is really quite wrong. Performance car /= sports car. Sports cars are light and nimble by definition. They are usually fast, but this is not a rule. There have always been sedans that are faster in a straight line than most sports cars. There have always been sports cars that are not very fast at all. None of this is new, and claiming otherwise is ahistorical. Even back in the '60s, a sports car enthusiast would…

And the Tesla plaid is the fastest nurburgring sedan ever made. Go ahead, say that's not a sports car.

You just said it's not a sports car. It's a sedan.

No one would dispute that it's a performance car. No one would dispute that it's very fast. But none of that matters here, because it weighs 5,000 lbs and has four doors. A Spitfire is not a muscle car, a Camaro is not a superbike, a 917 is not a performance sedan, and a Plaid is not a sports car.

You can, of course, use the word however you want. Words change meaning over time. But if you want to claim that sports car enthusiasts have moved the goal posts, you need to know where they were set in the first place. I am using the word in roughly the same way enthusiasts have always used it, and you are not.

Also, the Tesla Plaid is not the fastest sedan on the Nurburgring. It is the sixth fastest. Note that the top five times were set before Tesla's run.

https://www.hotcars.com/fastest-sedans-around-the-nurburgrin...

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

#273

Post by TaylorAlexander »

The_Double wrote: post #270
TaylorAlexander wrote: post #249

Earlier quoted context omitted.

They could boost with super capacitors.

Super capacitors are highly overrated by the general public. They really aren't that much better than lithium ion except for in a very narrow power/time bandwidth.

The comment I was responding to was lamenting the potentially slow speed of chemical reactions in batteries, so I recommended super capacitors specifically for the case where a higher rate of discharge is required. I agree lithium is potentially good enough there, I am merely speculating on solutions in the event that an ultra powerful vehicle really could exceed lithium’s capabilities.

As for the general public, I can’t say. I use super capacitors in the power system for my solar powered robot and I love them. Through that experience I have realized they have plenty of other applications.

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

#274

Post by froj »

diziet wrote: post #180

I am curious what sort of physical preparation the driver (Kate Maggetti) did to train for these runs, if any? Surprisingly the average g-force is just under 3 g.

3g for less than a second is really not to that much. Most people can easily withstand 3g sustained for minutes with (almost) no preparation. Just don't forget to breathe and maybe contract your leg muscles a bit. Many can go up to 7g sustained with half a day of training.

[1] https://gforce.ch/

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

#275

Post by bborud »

unsupp0rted wrote: post #268
bborud wrote: post #74

Earlier quoted context omitted.

Then there's the Brabham BT46 "Fan car" that actually raced in F1. Once. Before it was banned. :-) https://youtu.be/B294RfWj1QE?si=jxYpIgwtH44at6Bq

It was "voluntarily" withdrawn after one race, even though it wasn't contrary to the rules

You are correct.

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

#276

Post by bborud »

emmelaich wrote: post #174
bborud wrote: post #74

Earlier quoted context omitted.

Then there's the Brabham BT46 "Fan car" that actually raced in F1. Once. Before it was banned. :-) https://youtu.be/B294RfWj1QE?si=jxYpIgwtH44at6Bq

Huh the Nick Mason credited with being a McLaren F1 owner is the drummer from Pink Floyd.

Nick Mason has a pretty significant collection of cars. Back in the day he used to take his kids to school in his Ferrari 250 GTO. These days the car is so valuable I got the impression he has to call his insurance company to get permission to take it out on the road. Years ago he published a book called "Into the red" with some of his cars. The book had a companion CD of the engine noise made by a selection of the cars. They took each car to the track to record it.

Perhaps the most intense car he owns must be the BRM V16 which, to quote someone who saw it race back in the day "would make your ears bleed". https://youtu.be/fZMPDCNyQxE?si=e97ihEFRW7DU_UcC

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

#277

Post by xcv123 »

The_Double wrote: post #270
TaylorAlexander wrote: post #249

Earlier quoted context omitted.

They could boost with super capacitors.

Super capacitors are highly overrated by the general public. They really aren't that much better than lithium ion except for in a very narrow power/time bandwidth.

> except for in a very narrow power/time bandwidth

Which is exactly the scenario we are discussing. Drag races are only a few seconds.

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

#278

Post by radicalbyte »

chen_dev wrote: post #220
radicalbyte wrote: post #7

Earlier quoted context omitted.

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).

Interesting topic. A pretty good video about this: https://www.youtube.com/watch?v=ZMQbHMgK2rw

That's where I heard about it in the first place :)

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

#279

Post by Rastonbury »

elmerfud wrote: 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.

Racing rules are not generally updated because ground effect (powered or not) is a safety concern because losing traction through a corner suddenly when it fails can be catastrophic. This is why it was banned in F1 in the 80s, damage or getting lifted up and the car will suddenly fly off the track.

Another modern electric fan car which holds the goodwood record: https://youtube.com/watch?v=TptzkkbC1vE

Post reply on HN