Randall Munroe @xkcd.com · May 12 Pullback Drive xkcd.com/3244/
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Can we get a windup key to go with it?
How big of a flywheel would a car need to drive 100,000 miles without ever recharging?
Hamburger
That's my favourite type of car. Here's mine
“You’re gonna want to avoid table edges.”
very funny, but my brain can't help but think about how devastating that coil spring could be in a crash...
A car that works solely on clockwork? This has to be a wind-up!
I hear it has trouble with high hills.
Hey, if it works
As a kid knew another kid who was sure it would go further if you kept pulling back after the clicks so he'd pull back, hold the drive wheels, and pull back again like 10-20 times and then get super excited about "how far it went" even though it didn't actually go any further than it would've
Next up - trains that get their power from the rails. No, not the third rail. The rails. Better not step on one!
i propose retractable floorboards, to enable easy winding, call it Step 'n' Go
Can we get a "What if...?" of how feasible this would actually be?
I am reminded of compressed air cars being developed. Charge it up with compressed air and that drives it up to 100 km
From a Italian car magazine in the early sixties.
we're going to be pushing Teslas up hills once the grid goes down
I give you the flywheel (especially the Oerlikon Gyrobus) and the hydraulic accumulator. www.transportengineer.org.uk/content/feat...
No button on top?
“That sounds really dangerous — think how much energy must be stored in that spring!”
If we had a somewhat common-sized sedan, how much distance could we theoretically achieve via a mechanism with such size?
So much better than my first car that could only go straight while going forward, and to turn you had to go in reverse and it'd go backwards in a circle.
What if you need to reverse tho?
Do not try to repair it yourself
It's all good until you realize that the car doesn't have a reverse gear.
"There's a convenient panel under the driver and each passenger's feet so you can slide it open and pull back without getting out of the car..."
so I take it the hamster-wheel engine is a no-go.
Park it in the grandfather garage, lash it to the recharge pulley, and pull the chain to lift the weights off the floor - your car should be done charging in twenty minutes.
A certain white house occupant might think this is a legit way to drive uphill.
Isn't this how Elon's vehicles work?
"Our next model will be push-forward and use a flywheel for energy storage. We recommend ordering from a dealer more than 200km away to get a fully charged car."
Storing energy is the key. Would be funny to calculate a spring with 50 kwh. And the efficiency.
Sounds super-safe.
This brought back memories and I could hear the clicking sound in my head followed by the sound when I let go.
“What’s the giant slot in the back for?” “Oh, this is a special model that also carries a giant penny.” “Get a lot of requests for those?” “Just from one guy named Bruce Wayne.”
Pretty sure this is how the Smart Fortwo actually works.
Back in my day, it was a twisted elastic band. They don't make them like they used to.
Title text: ""How does the spring not run out almost immediately?" "We pull it back REALLY far."" Alt text: https://explainxkcd.com/3244#Transcript
For reliability, always go for the balloon driven model.
In a strange, roundabout way, this is sort of the concept behind regenerative braking