JIDOKA
JIDOKA - the Japanese term meaning automation. In this form of automation the machinery itself is checking the parts produced for defects after processing. With this constant checking of process quality deviations can be directly detected and when defects occur the complete process is automatically stopped until the problem is solved.
You might have come across the word autonomation, which is simply a combination of the words autonomous and automation that describes the automation with still human interactions. JIDOKA has to be seen as a manufacturing principle rather than a methodology. The idea behind JIDOKA is that all machines in the process chain can run without a dedicated operator checking for process stability and quality outcome. If there is a defect or non-conformity of the process, the machine shuts itself down, preventing the defective parts of getting passed on the downstream process steps and for this reason it prevents producing scrap.
In the Toyota Production System, autonomation is one of the main pillar and is also known as intelligent automation as it is firstly focusing on the quality and the ability of a self running system rather than just focusing on the output. You might have also heard the description of automation with a human touch - if a deviation occurs the machine itself will stop the complete manufacturing process and only with the interaction of an operator, after the problem is solved, it can continue production. The upside is pretty clear - you will not produce any defective parts or waste value adding activities on non-conforming components.
With the use of the JIDOKA principle a number of advantages are coming with it:
Processing of non-conforming parts is immediately noticed, so that neither scrap nor rework occurs. Furthermore, no defective parts are passed on to the downstream processes steps
Since the defects are detected automatically, a 100% end of line inspection is no longer needed within the scope of quality assurance
With the help of automatic error detection, operators are no longer needed to monitor machinery, which is no-value adding activity anyway, so it can be declared as waste in the form of waiting time
Operators have now the freedom to perform multiple tasks during the same time or are able to dedicate themselves to new tasks at all
Maintenance activities will also decrease as crashes or malfunction due to the passing on of non-conforming parts is avoided
JIDOKA is the basis of analyzing the root cause of failures and implement sustainable counter measures to avoid these of occurring again
