As it seems poka-yoke is a Japanese term, that simply means mistake-proofing .
It was originaly decribed as baka-yoke ,that means fool-proofing ,later it was changed to poka-yoke, may be thinking that there is no fool proof system to completely illuminate human mistakes.
Poka-yoke first introduced by, Mr.Shigeo Shingo as part of Toyota Production system.
Poka-Yoke is system, arrangement or constraint that restrict equipment or operator mistake.This system or arrangement may be in the form of instructions, extra electrical or mechanical device or in the form of some restrictions.
In our day-to-day life we see lots of poka-yoke to make our life safe and convenient.
If your two wheeler is in gear, you cant start it unless you press clutch, that arrangement is poka-yoke. In elevator, you cant open floor door unless elevator comes to your floor, that arrangement is called poka-yoke.
In your organisation if any problem arises, after finding its root cause you can prevent it by implementing a kind of poka-yoke there. The best utilization of poka-yoke is while installing any new machine, equipment or system ,think about the problems related to its operation or functioning ,and think poka-yoke.
Mass Production –
We found best usefulness and utilization of poka-yoke in mass production, where 100% inspection is not possible, so you have to target on less mistakes.
Any negligence or mistake in mass production will result in total lot rejection, that means a heavy loss by all means.
So that, in mass production (line production) you have to constraint at stages ,operations and movement.All these have to go under surveillance.
For an example we will take ,a weldshop asembly line of press shop.
In this case the poka-yoke will be for confirmation of,
- Shape of job
- Number of operations
- Number of spots per stage
- Number of loose parts required to assembled
- Number of studs to be projected
- Number of jobs to be filled in a pallet.