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Highway to [Hazmat] Hell!

SFOGuy says...

Driver was so scared he ran into the opposing lanes of traffic; trying to put concrete between him and the cooking off cylinders...If I was seeing that correctly...

LiquidDrift said:

Ha, if you see the driver running for it, probably a good idea to BACK UP!

4 Revolutionary Riddles Resolved!

newtboy says...

Calling him out on #1, he asked "what is this Object (in the cylinder)?". Honey and ping pong balls are not a single object.

Also the bicycle question, you need a rear sprocket about twice the size (or larger) of the front one to negate the wheel/crank ratio. Only custom bikes made for this question would have that gearing...so technically he's right but no one will have those results. (Edit:with the possible exception of Krusty, because his crank may be larger than his tiny wheel)

Rope Start a Car With a Dead Battery

newtboy says...

Yes, one wheel.
Because he has a car with a differential and the other wheel is stationary, all the rotational energy goes to the transmission, clutch, then flywheel, then crankshaft. By putting it in low gear, he gains enough mechanical advantage to spin the motor past top dead center on a cylinder and has enough battery power left to get a spark (i think he doesn't spin it fast enough to generate one), and once one cylinder fires, it spins itself up to proper rpms.
This only works on open diffs, manual transmissions, and smaller, low compression motors. You could never pull hard enough to start a big v8 like this unless your name is Magnus.

toferyu said:

Interesting.
Did he lift only one front wheel ?
If so how could that work, if not how does he lift both front wheels at the same time ?

Freevalve Camless Engine

robbersdog49 says...

They're using port injection, so without the engine turning there's nothing to pull the fuel into the cylinder.

I love all this technology though, I'm a real petrol head but I really do think this is the dying throws of the internal combustion engine. Electric motors just have so many advantages and the disadvantages are disappearing fast.

Payback said:

I've heard camless engines don't need starters. They just squirt a bit of fuel into a combustion-cycle (down stroke) cylinder and fire the plug.

Freevalve Camless Engine

Lord of the Lathes - The Fellowship of the Lathe

Ashenkase (Member Profile)

Working Miniature V8 Paper Engine

nock says...

Energy is neither created nor destroyed. A V8 converts gasoline into CO2, water and heat which increases pressure within a cylinder and in turn propels a piston that moves the car. This uses air to move a piston (and could be used to move a car). Gas = air in this example.

The Tech That Could Fix One of Wind Power's Biggest Problems

Drachen_Jager says...

That was my first thought as the problem this fixed. Because it's a solid cylinder visually, birds would be far less likely to get caught, rather than by the fast-moving blades of a normal turbine that chop through apparently clear sky.

Payback said:

Looks like it's more wildlife friendly too.

A Ford Flathead V-8 Rebuild Time-lapse

newtboy says...

At 1:50, they appear to be making the cylinder hole larger. They would then either 1)buy new pistons to fit the larger bore or 2) if they just took off a tiny bit to remove a scratch and it's still within tolerance they could just reuse the old pistons with new rings. In this case, those certainly looked like new pistons, which should be matched to the bore they just cut. Notice at 3:48 you can see ".030" stamped into it, which likely means .030 inches over stock.
At 2:05, I think they are 'dressing' the bore, which puts a cross hatch pattern in the cylinder wall that helps the rings seat and seal.

As to your side note...it's a style choice. Some people love the old, stock, unrefinished body paired with new running gear for a car that looks like junk but runs like a top. At least that's my guess...and that's how both of my cars are built.

RFlagg said:

So here's a question. When they redrill the holes at 1:50 and 2:05, does it not make the bore bigger and therefore allow more gas to escape the pistons?
Side note, I have to wonder why they didn't restore the truck itself while the engine was out being rebuilt.

Caught My Chicken Sleeping

MilkmanDan says...

One sample "weird chicken behavior" is psychotically aggressive bantam (miniature) roosters.

Too small and ill equipped (not much spur, etc.) to do any damage to a human, but they *act* like they think they are velociraptors or something. Bring food in, fill their water, get vaguely close to them ... they attack your feet. My dad taught me to put my shoe between their legs and lift/kick them into a wall -- pretty hard. Stuns / dazes them for a minute or so -- long enough to fill their feed or whatever. But stay longer than that and they'll be right back to attacking your feet.


On the female side, hens sometimes choose very bizarre locations to lay their eggs. We had a metal cylindrical feeder thing with a tray at the bottom -- fill cracked corn or whatever into the cylinder (open on top), and it will gravity flow down as they eat some out of the bottom tray. We had one hen that liked to jump in the top of that cylinder (maybe 10 inch diameter) and then lay eggs on top of the food in there. Extremely tight fit, no room to move -- like putting your arm in a Pringles can. Sometimes she got stuck if the surface of the food was too far down.

I've even seen a hen that sat on the surface of a bough in a cedar tree. Enough branch and cedar foliage to hold up the hen's body, but then we found an egg right under her on the ground -- not dense enough material to actually keep the egg from falling through. The egg was broken, but the hen just stubbornly sat in that tree for a day or two, not realizing what had happened.

ant said:

Like?

Throwback on a Comeback: The Last Cassette Tape Factory

oritteropo says...

Too late! There is at least one guy out there producing wax cylinder recordings...

Mordhaus said:

"I don't really understand this one. What's next? Edison wax cylinders?"

Shush, don't give the hipsters any ideas.

Throwback on a Comeback: The Last Cassette Tape Factory

Drifting a Top Fuel dragster

Tesla Model S driver sleeping at the wheel on Autopilot

bremnet says...

The inherently chaotic event that exists in the otherwise predictable / trainable environment of driving a car is the unplanned / unmeasured disturbance. In control systems that are adaptive or self learning, the unplanned disturbance is the killer - a short duration, unpredictable event for which the system is unable to respond to within the control limits that have been defined through training, programming and/or adaptation. The response to an unplanned disturbance is often to default to an instruction that is very much human derived (ie. stop, exit gracefully, terminate instruction, wait until conditions return to controllable boundary conditions or freeze in place) which, depending on the disturbance, can be catastrophic. In our world, with humans behind the wheel, let's call the unplanned disturbance the "mistake". A tire blows, a load comes undone, an object falls out of or off of another vehicle (human, dog, watermelon, gas cylinder) etc.

The concern from my perspective (and I work directly with adaptive / learning control systems every day - fundamental models, adaptive neural type predictors, genetic algorithms etc. ) is the response to these short duration / short response time unplanned disturbances. The videos I've seen and the examples that I have reviewed don't deal with these very short timescale events and how to manage the response, which in many cases is an event dependent response. I would guess that the 1st dead person that results from the actions or inaction of self driving vehicles will put a major dent if not halt to the program. Humans may be fallible, but we are remarkably (infinitely?) more adaptive in combined conscious / subconscious responses than any computer is or will be in the near future in both appropriateness of response and the time scale of generating that response.

In the partially controlled environment (ie. there is no such thing as 100%) of a automated warehouse and distribution center, self driving works. In the partially controlled environment where ONLY self driving vehicles are present on the roadways, then again, this technology will likely succeed. The mixed environment with self driving co-mingled with humans (see "fallible" above) is not presently viable, and I don't think will be in the next decade or two, partially due to safety risk and partially due to management of these short timescale unplanned disturbances that can call for vastly different responses depending upon the specific situation at hand. In the flow of traffic we encounter the majority of the time, would agree that this may not be an issue to some (in 44 years of driving, I've been in 2 accidents, so I'll leave the risk assessment to the actuaries). But one death, and we'll see how high the knees jerk. And it will happen.

My 2 cents.
TB

ChaosEngine said:

Actually, I would say I have a pretty good understanding of machine learning. I'm a software developer and while I don't work on machine learning day-to-day, I've certainly read a good deal about it.

As I've already said, Tesla's solution is not autonomous driving, completely agree on that (which is why I said the video is probably fake or the driver was just messing with people).

A stock market simulator is a different problem. It's trying to predict trends in an inherently chaotic system.

A self-driving car doesn't have to have perfect prediction, it can be reactive as well as predictive. Again, the point is not whether self-driving cars can be perfect. They don't have to be, they just have to be as good or better than the average human driver and frankly, that's a pretty low bar.

That said, I don't believe the first wave of self-driving vehicles will be passenger cars. It's far more likely to be freight (specifically small freight, i.e. courier vans).

I guess we'll see what happens.



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