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I'm an industrial engineer, so this is all right up my alley! My favorite example is a two-part foam injection machine. They needed to change the injection hea

I'm an industrial engineer, so this is all right up my alley! My favorite example is a two-part foam injection machine. They needed to change the injection head, and accidentally put it on backwards. The parts mixed and worked their way back in the supply lines, solidifying along the way. Hundreds of thousands of dollars in lost productivity, multiple weeks to get it fixed. They promptly switched the coupling so it was impossible to put the injection head on backwards.

chriswarbo 5y ago
A Proton rocket launch failed in 2013, supposedly due to sensors being installed backwards: https://en.wikipedia.org/wiki/Proton-M#Notable_launch_failures https://en.wikipedia.org/wiki/Proton-M#Notable_launch_failur... The Genesis sample-return capsule crash-landed due to the accelerometer controlling the parachute deployment being installed upside-down: https://en.wikipedia.org/wiki/Genesis_(spacecraft)#Mishap_Investigation_Board_(MIB) https://en.wikipedia.org/wiki/Genesis_(spacecraft)#Mishap_In...
- akavel 5y ago
  And notably, as a kinda higher-level challenge towards poka-yoke...: The improper installation apparently required some considerable physical effort, which, somehow did not raise any alarm at GKNPTs Khrunichev's assembly plant in Moscow. (...) By July 13, investigators simulated the improper installation of the DUS angular velocity sensors on the actual hardware. As it turned out, it would be very difficult to do but not impossible. To achieve that personnel would need to use procedures and instruments not certified either by the design documentation or the installation instructions. As a result, the plate holding the sensors sustained damage. Yet, when the hardware recovered from the accident was delivered to GKNPTs Khrunichev, it was discovered that the nature of the damage to the plate had almost exactly matched the simulated version. (via: http://www.russianspaceweb.com/proton_glonass49.html http://www.russianspaceweb.com/proton_glonass49.html) In other words: poka-yoke, meet hammer... (To make it clear, I absolutely love the idea of poka-yoke, and find it great help in software development as well; still, I find the story both hilarious and educative ;) )
kristofferc 5y ago
Another (smaller) example is the detachable controllers on the Nintendo Switch ("Joy-Con") which are very hard to remove if you accidentally reattach them upside down.

chriswarbo 5y ago

A Proton rocket launch failed in 2013, supposedly due to sensors being installed backwards: https://en.wikipedia.org/wiki/Proton-M#Notable_launch_failures https://en.wikipedia.org/wiki/Proton-M#Notable_launch_failur... The Genesis sample-return capsule crash-landed due to the accelerometer controlling the parachute deployment being installed upside-down: https://en.wikipedia.org/wiki/Genesis_(spacecraft)#Mishap_Investigation_Board_(MIB) https://en.wikipedia.org/wiki/Genesis_(spacecraft)#Mishap_In...

akavel 5y ago
And notably, as a kinda higher-level challenge towards poka-yoke...: The improper installation apparently required some considerable physical effort, which, somehow did not raise any alarm at GKNPTs Khrunichev's assembly plant in Moscow. (...) By July 13, investigators simulated the improper installation of the DUS angular velocity sensors on the actual hardware. As it turned out, it would be very difficult to do but not impossible. To achieve that personnel would need to use procedures and instruments not certified either by the design documentation or the installation instructions. As a result, the plate holding the sensors sustained damage. Yet, when the hardware recovered from the accident was delivered to GKNPTs Khrunichev, it was discovered that the nature of the damage to the plate had almost exactly matched the simulated version. (via: http://www.russianspaceweb.com/proton_glonass49.html http://www.russianspaceweb.com/proton_glonass49.html) In other words: poka-yoke, meet hammer... (To make it clear, I absolutely love the idea of poka-yoke, and find it great help in software development as well; still, I find the story both hilarious and educative ;) )

kristofferc 5y ago

Another (smaller) example is the detachable controllers on the Nintendo Switch ("Joy-Con") which are very hard to remove if you accidentally reattach them upside down.