ihunter2839 (u/ihunter2839)

ihunter2839 commented on New world record with an electric racing car: From 0 to 100 in 0.956 seconds ethz.ch/en/news-and-event... · Posted by u/ldes

elromulous · 2 years ago

Is this for some kind of [European?] [electric?] Formula SAE equivalent?

I took part in formula SAE ~20 years ago! Some of the first and most rewarding engineering work I've done.

ihunter2839 · 2 years ago

Yes, or maybe more accurately - we are the American equivalent of Formula SAE Germany. The German teams are significantly more advanced and better funded, with some of the teams running custom built electric inhub motors (something that's unheard of here in the US)

I am currently on San Jose States Formula SAE team - we merged our electric and combustion teams last year to go all electric since it's where the stiffest competition exists. If we could secure sponsorships we'd love to take our car to Germany!

ihunter2839 commented on Top Russian rocket scientist dies from ‘mushroom poisoning’ lbc.co.uk/news/russia-sci... · Posted by u/belter

renegade-otter · 2 years ago

This is not really suspicious. I regularly went foraging for shrooms in Ukraine with my gram gram, but I was not allowed to pick anything, of course. It requires expertise.

In that part of the world, this is very common, and so are the cases of people poisoning themselves because they think they are good at it.

If you can't relate - think of all the "gun people" who think they are experts on gun safety and then they end up shooting themselves by accident.

ihunter2839 · 2 years ago

This is not an accurate take. It does not require some great expertise to identify edible mushrooms, and in cultures where mushroom consumption has been common for hundreds of years (such as Russia), basic identification techniques are well known.

There are some edible mushrooms with poisonous look alikes - there are plenty other edible mushrooms without those deadly cousins. If this gentleman had made it 70+ years without issue, it is rather unlikely he would have some issue now.

As the saying goes: there are old foragers and bold foragers, but there are not old and bold foragers.

ihunter2839 commented on Rooftop wind energy innovation claims 50% more energy than solar at same cost pv-magazine.com/2022/10/1... · Posted by u/fairytalemtg

Panino · 3 years ago

> Aeromine said unlike conventional wind turbines that are noisy, visually intrusive, and dangerous to migratory birds, the patented system is motionless and virtually silent.

I've been a supporter of wind energy for 30 years and it's my favorite generation source. I want to believe the claims of this company, but the above quote is activating my spidey senses. Conventional wind turbines are not a serious threat to birds. According to Homebrew Wind Power by Dan Bartmann and Dan Fink, here are the causes of bird fatalities per 10000 fatalities (page 28):

  5500 Buildings / Windows
  1000 Cats
  1000 Other
  800 Power Lines
  700 Vehicles
  700 Pesticides
  250 Communication Towers
  <1 Wind Turbines

Many other sources agree.

Any wind turbine company will know this. For one to spread this lie makes me doubt their other claims. I hope they're right about price per watt but I have serious doubts.

That said, I would LOVE to have affordable grid-tied residential wind to complement my rooftop solar. It's not an easy problem to solve.

ihunter2839 · 3 years ago

From what I understand, one of the big bird issues with turbines is that birds of prey like hawks, eagles, and falcons don't generally look forward but down as they scout for prey, and thus are likely to fly into turbine blades. I believe some turbines have cameras systems to detect birds in the vicinity of the blades and either make a noise to alert the bird or maybe even bring the turbine to a halt. This is really only an issue for large scale installations though, obviously wouldn't apply to low lying roof installations.

ihunter2839 commented on Students break acceleration world record for electric vehicles uni-stuttgart.de/en/unive... · Posted by u/giuliomagnifico

agloeregrets · 3 years ago

Aero might play in a tiny way at the 40-60 MPH space, not meaningfully enough.

As for tires, no actually you can go much further than this. The big detail is wear and heat caused by tire softness and pressure. Road car tires can't enable 0-100KPH much faster than 1.9s or so purely because they can't be so soft as crusing on the highway would cause excess wear(practicality), heat (Danger), and friction(Range).

Drag Racers can accelerate way faster, 0-60MPH in .8s.

ihunter2839 · 3 years ago

The aero packages for these vehicles create a pretty significant amount of downforce at relatively low speeds - for example, our car last season produced ~140 lbs of downforce at 35 mph.

Edit - A lot of that comes from the rear wing though, which the green team didnt run for this particular event.

ihunter2839 commented on Students break acceleration world record for electric vehicles uni-stuttgart.de/en/unive... · Posted by u/giuliomagnifico

ncmncm · 3 years ago

I wonder if they are allowed to put a fan in to suck it down to the road surface, offering better static friction to the tires. You would of course start the fan before the wheels.

That would mean you could get by with lighter-weight tires, an important concern.

ihunter2839 · 3 years ago

Yes, this car uses powered ground effects (PGE) to achieve the necessary downforce at low speeds (they mention this in an instagram post)

In Formula SAE in the US, PGE systems are not allowed, but in the European equivalent they are.

Take a look at the Speirling at Goodwood Festival of Speed for an awfully mean fan car. https://www.youtube.com/watch?v=xtvT2XYlcOY

ihunter2839 commented on Students break acceleration world record for electric vehicles uni-stuttgart.de/en/unive... · Posted by u/giuliomagnifico

jws · 3 years ago

That's an average acceleration around 2g. This seems beyond the limits of tires and friction. Do aerodynamic down forces kick in fast enough to make more force usable against the road at these relatively low speeds? Do the tires have more than static friction going for them (say, fine scale interlocking with the pavement)?

Drag racers can do 3gs, but that's at higher average speed.

ihunter2839 · 3 years ago

Although the other comments are correct about the 30mph optimization for the aero package, this car uses active underbody aero (aka, fans) to create additional downforce even when at a standstill. See the recent runs of the Speirling at Goodwood festival of speed to see a purpose built "fan car" in action.

Interestingly, this setup wouldn't be allowed due to rules in Formula SAE in the US but is legal in the german competition cause those teams are just built different.

Edit - Quick plug! If anyone is interested in supporting FSAE and the awesome engineering that goes into these cars, I am a member of the San Jose State team and our aero team is in need of HPC access to run their CFD simulations. My email is in my profile. Cheers.

ihunter2839 commented on “Crime Pays but Botany Doesn’t” crosses citizen science with environmentalism outsideonline.com/culture... · Posted by u/acdanger

showerst · 4 years ago

Count me as someone who has gotten more interested in the natural world thanks to Joey. His mycology stuff led me to Alan Rockefeller who is also super cool, and does great talks and videos.

ihunter2839 · 4 years ago

I learned that the two of them were housemates for a period of time while taking a mycology class from Alan - can you imagine being a fly on the wall in that place? What a colorful group.

ihunter2839 commented on Teaching is a slow process of becoming everything you hate dynomight.net/teaching/... · Posted by u/dynm

commandlinefan · 4 years ago

> every word of the assignment creatively misinterpreted

OTOH when I took operating systems I got an assignment that said “implement a job scheduler, using FIFO, LIFO or round-robin job scheduling”. So I picked FIFO, got it working and I had time left over so I thought, “what the hell? I’ll do LIFO too”. So I did, and I still had time so I took a crack at round-robin, but I didn’t have time so I turned it what I had, proud of myself for going above and beyond.

I got back a 66 on the assignment. I asked why and he said, “you didn’t even attempt round robin”. I pulled up the assignment where it VERY CLEARLY said “or” and he said, “well, it should have been obvious I meant ‘and’”.

ihunter2839 · 4 years ago

I have to say I think it's quite possible and comical that the professor interpreted your work on two of the three questions as additional evidence that you did know it should be an "and", since I would guess relatively few students would attempt any more than _one_ permutation if the assignment only asked for one.

Damned if you do, damned if you don't.

ihunter2839 commented on Dr. Bronner’s, the Soap Company, Dips into Psychedelics nytimes.com/2022/02/28/he... · Posted by u/wunderlust

xyzzy_plugh · 4 years ago

If you reversed the headline it would honestly make more sense. There's zero chance mind altering substances were not involved when Dr. Bronner's wrote the copy on their products. Just reading the bottles is a trip.

ihunter2839 · 4 years ago

Did you know that hemp was not used in Dr. Bronners soaps until the 90s?

I think it's well know that Emmanuel Bronner suffered from some mental illnesses - the man lost his family to the holocaust and was sent to a mental asylum upon arriving in America. Life was not necessarily kind to him but he seemed to do alright with the cards he was dealt.

I know when I first learned about the soap, I had a similar sentiment as you. As I have learned more about the history of Dr. Bronners, I have come to see that it is hard for me to imagine some of the trials that the generations before us have faced.

ihunter2839 commented on Dr. Bronner’s, the Soap Company, Dips into Psychedelics nytimes.com/2022/02/28/he... · Posted by u/wunderlust

NoSorryCannot · 4 years ago

Not OP but I have tried to get along with it several times and every time, it dried my skin out so bad that I would itch, crack, and bleed. Leaves everything "squeaking" like Ivory soap, which I also don't like.

I will use it for housekeeping but I don't let it near my body anymore.

ihunter2839 · 4 years ago

Everybody has different needs, so I can respect that it's not a perfect soap for all people.

That being said - are you diluting it or using it straight? I usually dilute 4 parts water to 1 part soap for handwashing / showering. Also, the Eucalyptus scent was harsher on my skin than others - I prefer the unscented, almond, or peppermint varieties.