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Poka-Yoke

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Re: Poka-Yoke

#31

Post by keskival »

The example is wrong:

"A simple poka-yoke example is demonstrated when a driver of the car equipped with a manual gearbox must press on the clutch pedal (a process step, therefore a poka-yoke) prior to starting an automobile."

You would typically put the car to a neutral gear before starting up the car, clutch isn't required.

Furthermore, if there was such a poka-yoke preventing start-up when the clutch isn't pressed, it would prevent the common safety procedure when a car doesn't start and is in a dangerous position, for example on rails or in the motorway. In such situations you would drive the car with the starter engine alone, putting the first gear on, release the clutch, and start the car, thus moving it forward slowly by the battery and the starter engine.

Re: Poka-Yoke

#32

Post by nrr »

keskival wrote: post #31

The example is wrong: "A simple poka-yoke example is demonstrated when a driver of the car equipped with a manual gearbox must press on the clutch pedal (a process step, therefore a poka-yoke) prior to starting an automobile." You would typically put the car to a neutral gear before starting up the car, clutch isn't required. Furthermore, if there was such a poka-yoke preventing start-up when the clutch isn't pressed…

A lot of newer[0] US domestic market manual transmission cars do, in fact, have an interlock that prevents the starter motor from getting power without the clutch pedal also being depressed. Of particular note, my 1984 Ford Bronco II, 1991 Mitsubishi Galant, and 2004 Honda Accord all had such an interlock.

0: This is basically everything after the three-on-the-tree/four-on-the-floor era. I have yet to drive anything with an overdrive gear that didn't require popping the clutch to crank the starter.

Re: Poka-Yoke

#33

Post by duskwuff »

dghf wrote: post #6
needle0 wrote: post #5

"Yoke" is pronounced like "yo K", not like the control wheel of an aircraft. (Then again, seeing how nobody pronounces Pokémon as Pokémon, I guess striving for accurate pronunciation is a lost cause)

> seeing how nobody pronounces Pokémon as Pokémon I say (and usually hear, from English speakers) "poker mon" (non-rhotically). Isn't that roughly correct, allowing for differences between English and Japanese vowels?

If you're going for "correct", the first two syllables should rhyme with "okay". That's what the accented é is trying to hint at.

Re: Poka-Yoke

#34

Post by wheelinsupial »

Y_Y wrote: post #3

I like collecting little ideas like this. Slightly meta-ironically I'd describe the genre as "just abstract enough to be useful nuggets of knowledge" and I have an org file full of them. The hard part is I don't know any better name for such "concepts" so I can't search for other people's lists. Does anyone else keep a similar collect or have advice for finding more? (For example Gurwinder sometimes posts lists like…

I’m not sure if it’s similar to what you’re talking about, but there is something called “TRIZ” that’s a collection of “things” we were introduced to in a mechanical design class I took.

https://en.m.wikipedia.org/wiki/TRIZ

Re: Poka-Yoke

#35

Post by mikestew »

Brianwiz wrote: post #30

This reminds me of how the diesel spout at the gas station is too big to fit into a car that takes gasoline.

Not to big to fit in the opening of a motorcycle gas tank, as I once painfully discovered.

Re: Poka-Yoke

#36

Post by HeyLaughingBoy »

nrr wrote: post #32
keskival wrote: post #31

The example is wrong: "A simple poka-yoke example is demonstrated when a driver of the car equipped with a manual gearbox must press on the clutch pedal (a process step, therefore a poka-yoke) prior to starting an automobile." You would typically put the car to a neutral gear before starting up the car, clutch isn't required. Furthermore, if there was such a poka-yoke preventing start-up when the clutch isn't pressed…

A lot of newer[0] US domestic market manual transmission cars do, in fact, have an interlock that prevents the starter motor from getting power without the clutch pedal also being depressed. Of particular note, my 1984 Ford Bronco II, 1991 Mitsubishi Galant, and 2004 Honda Accord all had such an interlock. 0: This is basically everything after the three-on-the-tree/four-on-the-floor era. I have yet to drive anything…

My 1987 Toyota 4x4 pickup had such an interlock. It also had a switch to disable the interlock, allowing you to start the truck in gear. A very useful feature when you were stalled on a very steep hill offroad. Starting in 1st gear, low range basically turned it into an electric car for a few seconds :-)

Re: Poka-Yoke

#38

Post by pornel »

GuB-42 wrote: post #11
csours wrote: post #10

"Anything that can go wrong, will go wrong" - Murphy "Dubble check that spelIng" - Muphry Murphy was a rocket engineer. One day their assistant plugged in a non-keyed connector upside down. It was very easy for that to go wrong. Another time, in another place, a rocket assembly worker hammered in a keyed connector - upside down. It was harder for that to go wrong, but, uh, life finds a way.

"If you design something to be idiot proof, the universe will design a better idiot."

This one is funny, but I don't like this saying.

It may be interpreted in a defeatist way that poka-yoke is pointless, because it can always be defeated, but in reality improvements that save almost all "idiots" are still worthwhile.

An interlock in the microwave doors can't stop a better idiot from disassembling it, but it prevents a lot of everyday mistakes, and that's super helpful.

Re: Poka-Yoke

#39

Post by eternityforest »

myself248 wrote: post #20

In my industry, we mostly use the term to refer to mechanical features, typically keyways, that prevent connectors from being mated incorrectly. Suppose you have a module with 50 pins worth of connectors, but because some of the signals are in different harnesses which get installed at different times, you can't just use a 50-pin connector. For this example let's say it's sensible to break it up as 20+20+10. You woul…

The other solution is to make it trivial to both fix and detect errors, by using the same pinout so nothing gets damaged, and letting the computer tell you if everything is right.

But with a car that's not really practical as things may not be accessible and easy to swap around.

Re: Poka-Yoke

#40

Post by eternityforest »

csours wrote: post #10

"Anything that can go wrong, will go wrong" - Murphy "Dubble check that spelIng" - Muphry Murphy was a rocket engineer. One day their assistant plugged in a non-keyed connector upside down. It was very easy for that to go wrong. Another time, in another place, a rocket assembly worker hammered in a keyed connector - upside down. It was harder for that to go wrong, but, uh, life finds a way.

https://spacecraft.ssl.umd.edu/akins_laws.html
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