6 ms·

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://w

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-chaparral-2j-history/ 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.

radicalbyte 3y ago
In Micromouse (https://en.wikipedia.org/wiki/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).
- underlines 3y ago
  radicalbyte, you're absolutely right that the use of fans in Micromouse increases the traction, and therefore the speed at which the maze is solved. Suction allows for impressive performances. However, a small caveat that might be worth considering is that while the suction indeed increases speed, it might be more accurate to say that it primarily improves acceleration instead of car speed: The issue often lies with achieving rapid acceleration rather than with maintaining high speed. Even systems with relatively low traction can reach high speeds given enough time and distance, but the ability to accelerate quickly is crucial in competitions like Micromouse.
  - HPsquared 3y ago
    Speed = ∫(acceleration) dt
    - anikan_vader 3y ago
      Sure, but once you have speed you can use aerodynamics to get grip (e.g., F1 cars). So this is really only relevant if you need acceleration from low speed.
      - AmericanChopper 3y ago
        F1 has featured a car that used a fan to generate downforce. https://en.m.wikipedia.org/wiki/Brabham_BT46 https://en.m.wikipedia.org/wiki/Brabham_BT46 An issue with aero features (other than not producing their effects at low speed) is their ability to stall. Ground effect was especially dangerous (back when high-ground-effect designs were allowed) because if it stalls during a high speed corner (say from driving over a bump, like a kerb maybe) you can instantaneously lose a huge amount of downforce, which is obviously quite dangerous.
    - epolanski 3y ago
      Exactly, thus you can simply integrate over a longer time span. But if you want to increase the acceleration you need traction, your tyres need to be glued to the asphalt. Since you don't have aerodynamic pressure at those speeds you need to suck the vehicle to the ground.
    - westurner 3y ago
      Derivatives of relative displacement as defined by a distance metric in a [e.g. metric tensor] space: Length = Point2 - Point1 Length * Time^-1 = Velocity or Speed Length * Time^-2 = Acceleration Length * Time^-3 = Jerk Length * Time^-4 = Snap or Jounce Length * Time^-5 = Crackle Length * Time^-6 = Pop Displacement (geometry) > Derivatives: https://en.wikipedia.org/wiki/Displacement_(geometry)#Derivatives https://en.wikipedia.org/wiki/Displacement_(geometry)#Deriva... Fourth, fifth, and sixth derivatives of position: https://en.wikipedia.org/wiki/Fourth,_fifth,_and_sixth_derivatives_of_position https://en.wikipedia.org/wiki/Fourth,_fifth,_and_sixth_deriv...
      - jameshart 3y ago
        Something weird about this is that humans very often ascribe the sensation of d^ns/dt^n, to feeling d^n-1s/dt^n-1. So people will say that something which accelerates quickly is 'fast'. Or they will say, when they feel themselves initially being pressed back into their seat as a plane starts its takeoff roll, that they are experiencing 'acceleration' when what they are experiencing is actually jerk. The thing is, you can't actually feel motion at a constant speed - so the only thing that tells you you are acquiring speed is your body's experience of acceleration - so when you feel yourself accelerating, you associate that with speed. Likewise, your body also can't really tell the difference between constant acceleration and just... being at a different angle, and maybe a bit heavier than normal. So it's when you experience changes in the apparent direction of 'down' and the overall 'weight' you're feeling that you think 'oh, we're accelerating'. My favorite way to get a sense of what acceleration, jerk and snap feel like is to focus on what happens when you're in a car that's braking hard. You're decelerating at a relatively constant rate while the brakes are applied - it feels as if 'down' is pointing slightly forward, meaning you'd be sliding off the seat if it weren't for your seatbelt holding you back. When the car finally stops though, there's a very abrupt change in acceleration - a 'jerk'. 'Down' switches to pointing straight down again, very quickly. You're pulled back into your seat. That's jerk. And specifically the sudden onset of that swing in what direction 'down' is pointing, and then its rapid disappearance is snap. Your body feels like it's being 'jerked' around when the car stops precisely because that motion has high snap - you experience a sudden high amount of jerk, then the jerk ends.
  - hanniabu 3y ago
    [flagged]
    - 0xDEF 3y ago
      So many old polite people on the Internet are going to be accused of being AI chatbots.
      - ojbyrne 3y ago
        Old polite people who can spell.
      - hanniabu 3y ago
        It has nothing to do with being polite and more to do with a recap of context, using similar language, before responding.
- chen_dev 3y ago
  Interesting topic. A pretty good video about this: https://www.youtube.com/watch?v=ZMQbHMgK2rw https://www.youtube.com/watch?v=ZMQbHMgK2rw
  - radicalbyte 3y ago
    That's where I heard about it in the first place :)
- mtillman 3y ago
  Gordon Murray was ahead of his time: https://en.m.wikipedia.org/wiki/Brabham_BT46 https://en.m.wikipedia.org/wiki/Brabham_BT46
sokoloff 3y ago
Fans (no pun intended) of sucker cars are likely to be interested in the Goodwood record setting run by the McMurtry Speirling car. https://www.youtube.com/watch?v=5JYp9eGC3Cc https://www.youtube.com/watch?v=5JYp9eGC3Cc
bborud 3y ago
Then there's the Brabham BT46 "Fan car" that actually raced in F1. Once. Before it was banned. :-) https://youtu.be/B294RfWj1QE?si=jxYpIgwtH44at6Bq https://youtu.be/B294RfWj1QE?si=jxYpIgwtH44at6Bq
- raleec 3y ago
  ...and it's current spiritual successors The McLaren F1 and now the GMA T.50 https://en.wikipedia.org/wiki/McLaren_F1 https://en.wikipedia.org/wiki/McLaren_F1 https://en.wikipedia.org/wiki/Gordon_Murray_Automotive_T.50 https://en.wikipedia.org/wiki/Gordon_Murray_Automotive_T.50
  - Nick87633 3y ago
    Huh, never knew that the F1 had floor suckers!
  - CarVac 3y ago
    From a Youtube interview with Gordon Murray I saw, the T.50 has fan-enhanced diffusers, the fan ingesting the boundary layer to prevent flow separation. It's not able to produce extra downforce at zero speed. The McMurtry Spéirling is more akin to this, with a 1.4s 0-60mph run.
- emmelaich 3y ago
  Huh the Nick Mason credited with being a McLaren F1 owner is the drummer from Pink Floyd.
  - ryukoposting 3y ago
    Suddenly I remember a Top Gear episode where Nick Mason drops off his F1 (maybe it was a Ferrari Enzo?) at the test track, then his personal helicopter lands on the strip, picks him up, and flies him out of the scene, all while "Money" by Pink Floyd plays in the background.
    - kQq9oHeAz6wLLS 3y ago
sjburt 3y ago
Interesting. This is a Formula Student car, the european version of the Formula SAE. Powered ground effects were banned a long time ago in Formula SAE, but it seems like Formula Student does allow them.
- gladoskar 3y ago
  It was disallowed for many years but is re-allowed since the 2022 season
glax 3y ago
Had the same thought, 0-100kmph in 3sec gives so much wheel spin. Must be a whole lot of electronic trickery ever invented from launch control, traction control to power management plus the mechanical stuff sticky tyres, down force. It amazes me how much faster we have got the last 6-7 years.
gladoskar 3y ago
These cars stem from the Formula Student, which since 2022 has re-allowed the previously forbidden "powered ground effect". But this car has an upgraded battery and powertrain beyond what the rules allow and they maybe also use tire warmers and potentially rubber/glue on the launch surface/tires
- KennyBlanken 3y ago
  A photo shows them using tire warmers and they're running Hoosiers, which are incredibly sticky tires. I have no idea what you're on about with "rubber/glue on the launch surface/tires." That's not a Thing.
  - aaronax 3y ago
    It is a thing. https://en.m.wikipedia.org/wiki/PJ1_TrackBite https://en.m.wikipedia.org/wiki/PJ1_TrackBite
Rastonbury 3y ago
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 https://youtube.com/watch?v=TptzkkbC1vE

radicalbyte 3y ago

In Micromouse (https://en.wikipedia.org/wiki/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).

underlines 3y ago
radicalbyte, you're absolutely right that the use of fans in Micromouse increases the traction, and therefore the speed at which the maze is solved. Suction allows for impressive performances. However, a small caveat that might be worth considering is that while the suction indeed increases speed, it might be more accurate to say that it primarily improves acceleration instead of car speed: The issue often lies with achieving rapid acceleration rather than with maintaining high speed. Even systems with relatively low traction can reach high speeds given enough time and distance, but the ability to accelerate quickly is crucial in competitions like Micromouse.
- HPsquared 3y ago
  Speed = ∫(acceleration) dt
  - anikan_vader 3y ago
    Sure, but once you have speed you can use aerodynamics to get grip (e.g., F1 cars). So this is really only relevant if you need acceleration from low speed.
    - AmericanChopper 3y ago
      F1 has featured a car that used a fan to generate downforce. https://en.m.wikipedia.org/wiki/Brabham_BT46 https://en.m.wikipedia.org/wiki/Brabham_BT46 An issue with aero features (other than not producing their effects at low speed) is their ability to stall. Ground effect was especially dangerous (back when high-ground-effect designs were allowed) because if it stalls during a high speed corner (say from driving over a bump, like a kerb maybe) you can instantaneously lose a huge amount of downforce, which is obviously quite dangerous.
  - epolanski 3y ago
    Exactly, thus you can simply integrate over a longer time span. But if you want to increase the acceleration you need traction, your tyres need to be glued to the asphalt. Since you don't have aerodynamic pressure at those speeds you need to suck the vehicle to the ground.
  - westurner 3y ago
    Derivatives of relative displacement as defined by a distance metric in a [e.g. metric tensor] space: Length = Point2 - Point1 Length * Time^-1 = Velocity or Speed Length * Time^-2 = Acceleration Length * Time^-3 = Jerk Length * Time^-4 = Snap or Jounce Length * Time^-5 = Crackle Length * Time^-6 = Pop Displacement (geometry) > Derivatives: https://en.wikipedia.org/wiki/Displacement_(geometry)#Derivatives https://en.wikipedia.org/wiki/Displacement_(geometry)#Deriva... Fourth, fifth, and sixth derivatives of position: https://en.wikipedia.org/wiki/Fourth,_fifth,_and_sixth_derivatives_of_position https://en.wikipedia.org/wiki/Fourth,_fifth,_and_sixth_deriv...
    - jameshart 3y ago
      Something weird about this is that humans very often ascribe the sensation of d^ns/dt^n, to feeling d^n-1s/dt^n-1. So people will say that something which accelerates quickly is 'fast'. Or they will say, when they feel themselves initially being pressed back into their seat as a plane starts its takeoff roll, that they are experiencing 'acceleration' when what they are experiencing is actually jerk. The thing is, you can't actually feel motion at a constant speed - so the only thing that tells you you are acquiring speed is your body's experience of acceleration - so when you feel yourself accelerating, you associate that with speed. Likewise, your body also can't really tell the difference between constant acceleration and just... being at a different angle, and maybe a bit heavier than normal. So it's when you experience changes in the apparent direction of 'down' and the overall 'weight' you're feeling that you think 'oh, we're accelerating'. My favorite way to get a sense of what acceleration, jerk and snap feel like is to focus on what happens when you're in a car that's braking hard. You're decelerating at a relatively constant rate while the brakes are applied - it feels as if 'down' is pointing slightly forward, meaning you'd be sliding off the seat if it weren't for your seatbelt holding you back. When the car finally stops though, there's a very abrupt change in acceleration - a 'jerk'. 'Down' switches to pointing straight down again, very quickly. You're pulled back into your seat. That's jerk. And specifically the sudden onset of that swing in what direction 'down' is pointing, and then its rapid disappearance is snap. Your body feels like it's being 'jerked' around when the car stops precisely because that motion has high snap - you experience a sudden high amount of jerk, then the jerk ends.
- hanniabu 3y ago
  [flagged]
  - 0xDEF 3y ago
    So many old polite people on the Internet are going to be accused of being AI chatbots.
    - ojbyrne 3y ago
      Old polite people who can spell.
    - hanniabu 3y ago
      It has nothing to do with being polite and more to do with a recap of context, using similar language, before responding.
chen_dev 3y ago
Interesting topic. A pretty good video about this: https://www.youtube.com/watch?v=ZMQbHMgK2rw https://www.youtube.com/watch?v=ZMQbHMgK2rw
- radicalbyte 3y ago
  That's where I heard about it in the first place :)
mtillman 3y ago
Gordon Murray was ahead of his time: https://en.m.wikipedia.org/wiki/Brabham_BT46 https://en.m.wikipedia.org/wiki/Brabham_BT46

sokoloff 3y ago

Fans (no pun intended) of sucker cars are likely to be interested in the Goodwood record setting run by the McMurtry Speirling car. https://www.youtube.com/watch?v=5JYp9eGC3Cc https://www.youtube.com/watch?v=5JYp9eGC3Cc

bborud 3y ago

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

raleec 3y ago
...and it's current spiritual successors The McLaren F1 and now the GMA T.50 https://en.wikipedia.org/wiki/McLaren_F1 https://en.wikipedia.org/wiki/McLaren_F1 https://en.wikipedia.org/wiki/Gordon_Murray_Automotive_T.50 https://en.wikipedia.org/wiki/Gordon_Murray_Automotive_T.50
- Nick87633 3y ago
  Huh, never knew that the F1 had floor suckers!
- CarVac 3y ago
  From a Youtube interview with Gordon Murray I saw, the T.50 has fan-enhanced diffusers, the fan ingesting the boundary layer to prevent flow separation. It's not able to produce extra downforce at zero speed. The McMurtry Spéirling is more akin to this, with a 1.4s 0-60mph run.
emmelaich 3y ago
Huh the Nick Mason credited with being a McLaren F1 owner is the drummer from Pink Floyd.
- ryukoposting 3y ago
  Suddenly I remember a Top Gear episode where Nick Mason drops off his F1 (maybe it was a Ferrari Enzo?) at the test track, then his personal helicopter lands on the strip, picks him up, and flies him out of the scene, all while "Money" by Pink Floyd plays in the background.
  - kQq9oHeAz6wLLS 3y ago

sjburt 3y ago

Interesting. This is a Formula Student car, the european version of the Formula SAE. Powered ground effects were banned a long time ago in Formula SAE, but it seems like Formula Student does allow them.

gladoskar 3y ago
It was disallowed for many years but is re-allowed since the 2022 season

glax 3y ago

Had the same thought, 0-100kmph in 3sec gives so much wheel spin. Must be a whole lot of electronic trickery ever invented from launch control, traction control to power management plus the mechanical stuff sticky tyres, down force. It amazes me how much faster we have got the last 6-7 years.

gladoskar 3y ago

These cars stem from the Formula Student, which since 2022 has re-allowed the previously forbidden "powered ground effect". But this car has an upgraded battery and powertrain beyond what the rules allow and they maybe also use tire warmers and potentially rubber/glue on the launch surface/tires

KennyBlanken 3y ago
A photo shows them using tire warmers and they're running Hoosiers, which are incredibly sticky tires. I have no idea what you're on about with "rubber/glue on the launch surface/tires." That's not a Thing.
- aaronax 3y ago
  It is a thing. https://en.m.wikipedia.org/wiki/PJ1_TrackBite https://en.m.wikipedia.org/wiki/PJ1_TrackBite

Rastonbury 3y ago

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 https://youtube.com/watch?v=TptzkkbC1vE