A commonly-used news story that the media loves to cover is when a famous company gets slapped with a product recall due to defects or malfunctions. If you think about the things you use in your home, products you buy from a retail store, electronics, and appliances that help make your life more convenient. Everything you use in your everyday lives, most of them are non-defective and last a long time thanks to production processes like Jidoka.
To give you an idea of how this process works, think of a car assembly line like the ones you see on TV where people work hand-in-hand with robots to build a vehicle. As each car moves along the assembly line, every employee has to perform some role or function to help create the finished product. When an employee discovers an abnormality or defect, that person will immediately hit the stop button, and all production ceases until the problem is corrected and is what Jidoka is all about.
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Jidoka is one of the most powerful business concepts to have originated from Japan. It was first implemented as part of the Toyota Production System (TPS) and lean manufacturing. This term is commonly known as “intelligent automation.” In simple terms, it can be described as automation with a human touch. When in practice, it is an automated process that is sufficiently aware of itself so that it detects product defects and process malfunctions, stops itself, and alerts the operator. This process enables an operation to improve quality at each process. Also, machines and individual employees are separated so that more efficient work can be completed. It is also one of the two pillars of the TPS system which also includes Just-in-Time.
When a problem first occurs, Jidoka highlights the causes of problems and work stops immediately. This concept originated in the early 1900s when the founder of the Toyota group, Sakichi Toyoda, invented a textile loom that would stop automatically if any thread broke. Before this invention was created, looms would often turn out piles of defective fabric if a thread would break. To prevent threads from breaking, each machine would have to be monitored by an operator very carefully. With Toyoda’s new invention, the high-quality fabric was produced at a faster speed than ever, and large productivity gains were made because one operator could handle several machines instead of one.
Jidoka is visible in almost all aspects of lean manufacturing when you examine it very carefully.
Its principles can be broken down into a few simple steps:
1. Discover an abnormality in the production process
3. Correct the immediate problem
4. Investigate and find out the root-cause of the problem
This principle not only applies to machines since it is about building quality into a process. Rather than inspecting a finished product at the end of the process, problems are identified early during production or as soon as they occur. Inspection still has a place in the production process, and it is still a powerful way of preventing defects from reaching the customer, but it does not take priority for identifying defects and abnormalities. When an inspection is done at the end of the process, significant amounts of defective products exist where Jidoka eliminates the possibility of this scenario occurring. Every individual in a lean company has the authority to stop the process. If an abnormality is discovered, problems and defects are highlighted, and actions are taken immediately.
Benefits of Jidoka
The principle of this lean method provides numerous benefits for manufacturing and production companies. These advantages can be broken down into three parts:
1. The reduction of repair costs
2. The reduction of recall costs
3. The minimization of lawsuits and compensations to consumers
Regarding repair cost reduction, goods that are produced with machines with no human supervision create an incredibly high cost for repairs. This is because there is an increased likelihood that products will be generated with defects. In addition to repair costs, there will be an excess of waste since many materials were reused to create products with defects which are then later destroyed or recycled again.
If products and goods are produced with machines only, there is a possibility of inherent defects. Detecting these defects with sampling is not always possible. Once the goods have been sent to market, there may be a product recall especially if the defects cause serious injuries or lead to loss of human life. If a product is a machine, the defect makes that product dangerous. If the defect is in a food product, it makes the food poisonous.
No company can stay in business for long if it is constantly in litigation from lawsuits or repeatedly paying compensation to consumers for producing defective products or goods. This lean technique helps to minimize lawsuits and compensations to customers which lead to reducing the company’s liability. Companies that are more vulnerable to lawsuits tend to be ones that manufacture their products and goods exclusively through an automated process whereas companies that employ Jidoka principles have a reduced chance and create fewer avenues for lawsuits.
What is Autonomation?
Autonomation is a combination of “autonomous” and “automation” and is a synonym of Jidoka. These words are interchangeable because applying this principal gives equipment the ability to autonomously distinguish good parts from bad ones without being monitored by an operator. In a process coined multiprocess handling, autonomation gets rid of eliminates the need for operators to monitor machines continuously. As a result, enormous productivity gains are made because one operator can handle several machines.
Autonomation either deals with product defects or process malfunctions. Regarding product defects, let’s look at the example of a press that is used for shaping a piece of metal. As each piece of metal passes along through the press, sometimes the part will break under the force of the machine. The traditional way of inspecting each piece of metal would require a worker to take a look at each piece by hand to ensure it is not broken. With the implementation of autonomation, output pieces of metal would be moved onto a jig that has a weigh scale. At this time, pieces of metal that do not fit securely into the jig or pieces that are out of weight tolerance would automatically cause the press to stop, and an alarm would be sounded to alert a worker.
When it comes to process malfunctions, let’s take a look at the same example of the piece of metal being shaped by the press. Output pieces are placed onto a conveyor belt by one machine. The conveyor belt will then move the pieces onto a second machine, for example, the press that shapes the metal pieces. During the process, there will be times when the press must stop for one reason or another. If the first machine continues running while pushing output pieces onto the conveyor belt which is also running, the pieces will eventually pile up and spill out onto the floor at some location. With manual inspection, a worker would have to watch the press and then stop the first machine then move on to the conveyor belt to stop it as well. Autonomation would automatically get a signal from the press when it stops, or another scenario such as the lack of weight of the metal piece would signal that the previous piece was not picked up by the press. In either situation, both the first machine and the conveyor belt would stop, and an alarm would be sounded to alert a worker.
How Lean Companies Uses Jidoka
Jidoka is used in lean manufacturing by detecting an abnormality using simple sensors and then stopping and highlighting the problem for an operator. In cases where there is a line stop, the operator will discover the abnormality and stop the line. The problem is then highlighted for everyone to see on an andon board. Companies also implement this principle in conjunction with other lean tools such as 5S, Total Productive Maintenance (TPM), Kanban, among many others.
Lean companies depend on the principles of Jidoka across other various lean manufacturing principles to employ visual management techniques that highlight whatever kind of normality occurs during the production process and then allows employees to take immediate action. In most production and manufacturing facilities, team leaders, managers, and supervisors are always encouraged to keep their eyes open as they walk through the production facility while employing Jidoka principles.
There are many advantages to using Jidoka since it is one of the most powerful management concepts. They include:
- Reducing the number of defective products as much as possible to become negligible as well as drastically decreasing production costs with the elimination of wastage
- Early identification of problems in the manufacturing process so that they are easily rectified as quickly as possible without causing further delay in production
- Improving product quality during the manufacturing process so that customers are satisfied when they buy those products
- Decreasing equipment repair and replacement costs since the instances of equipment breakdown are also reduced
- Fewer gaps in production and an increase in overall productivity
- Since process capability will become high, it reduces the need for full-time inspectors
- Allows workers to supervise more than one machine at the same time which reduces the need to employ more workers
- Employee morale is increased since they have the authority to interrupt production whenever a mistake is detected
Your Organization Can Benefit from This Technique
Jidoka is one of the most powerful management techniques that your organization can use to increase profitability and quality. As one of the central pillars of TPS and employed by lean manufacturing and production companies that want to meet the highest standards, Jidoka helps ensure that workers can always highlight, see, and correct problems in the manufacturing process.