Poka-yoke (sounds like poka yoke) is a funny-sounding Japanese term that means one of the tools of lean manufacturing. It turns out that we encounter it every day. Only in Russian does it sound like “principle of zero error” or “ foolproof».
In English, poka-yoke is literally translated as " avoid mistakes”, i.e. "Avoid Mistakes" And in practice, an adapted translation is used - mistake proofing or error proofing(error protection).
Poka-yoke are methods and devices that help to avoid errors in the production process, or to identify them in time so that they do not enter the next process in the form of defects.
Fool-proof devices protect not just from errors, but from errors caused by the human factor:
- inattention
- forgetfulness
- imprudence
- ignorance
- fatigue
- and even sabotage.
The principle of operation of poka-yoke is characterized by:
- 100% verification coverage
- fast feedback
- low cost and simplicity.
Poka-yoke devices work on the principle of pass no defect - do not miss a single defect.
History of the creation of poka-yoke methods
Poka-yoke aims to eliminate bugs based on the human factor. Error protection has been used in enterprises in one form or another long before the concept of poka-yoke was formed. Formalized this system in Toyota.
The inventor of the poka-yoke methods is the Japanese engineer Shigeo Shingo (1909-1990), an expert in the field of production and one of the creators of production system Toyota. Shigeo Shingo developed an approach Zero quality control(ZQC), or Zero Defects(zero defects).
The zero defects method is based on the belief that defects are prevented by such control of the production process, in which a defect will not occur even if a machine or a person makes a mistake.
The focus of quality control is shifting from verification finished products on the fact of marriage to prevent the occurrence of marriage at each stage of production.
At the same time, a key role in the prevention of defects belongs to the production personnel who are involved in the quality assurance process.
Poka-yoke or zero error method is one of the key aspects of ZQC. The poka-yoke system uses sensors or other devices that literally prevent the operator from making a mistake.
They regulate the manufacturing process and prevent defects in one of two ways:
- Control system- stops the equipment when a violation of the norm occurs, or blocks the workpiece with clamps so that it does not move further along the conveyor until it is processed as required. This is the preferred system as it is operator independent.
- warning system— sends a signal to the operator to stop the machine or fix the problem. Depends on the operator, so the human factor is not completely excluded.
Poka-yoke does not look for those responsible for mistakes, the purpose of the method is to find and eliminate weak spots on the production system that made the error possible.
poka-yoke device levels
Fool-proofing methods are divided into three levels in order of increasing efficiency:
- 1st level - detects inconsistency of parts or products. The system detects a defective part, but does not discard it.
- 2nd level - does not allow mismatch.The system prevents the defective part from being processed at the next stage of the production process.
- 3rd level - structural protectionfor example, the product is designed in such a way that it cannot be installed or assembled in an unintended manner.
Error protection principles
There are six principles or methods of error protection. They are listed in order of priority:
- elimination: This method eliminates the possibility of error by redesigning the product or process so that the problematic operation or part is no longer required.
Example : simplifying the product or connecting parts to avoid product or assembly defects. - substitution: To improve reliability, you need to replace an unpredictable process with a more reliable one.
Example : The use of robotics and automation to prevent manual assembly errors. Application of automatic dispensers or applicators for precise dosing of liquid materials. - A warning: Design engineers must design a product or process such that it is impossible to make a mistake at all.
Example: Design features of parts that only allow correct assembly; unique connectors to avoid misconnection of cables; symmetrical details that avoid incorrect installation. - Relief: Using certain methods and grouping steps makes it easier to complete the assembly process.
Example: Visual controls that include color coding, part markings. An intermediate box that visually controls that all parts are assembled. Drawing characteristics on parts. - Detection: Errors are detected before they move on to the next production process so that the operator can quickly correct the problem.
Example: Sensors in the manufacturing process that detect if parts are assembled incorrectly. - Mitigation: Trying to reduce the impact of errors.
Example: Fuses to prevent overloading of circuits due to short circuits.
Basic methods of poka-yoke
There are three types of error protection methods: contact methods, reading methods and sequential movement methods.
contact methods
Determine if a part or product is physically or energetically in contact with the sensing element. An example physical contact there may be a limit switch that presses down and gives a signal when its moving mechanisms touch the product. Example energy contact- photoelectric beams that sense when something is wrong in the object being checked.
The best contact methods are passive devices, such as guide pins or pulleys, that prevent workpieces from being misplaced on the conveyor.
Reading methods
Should be used when the workflow is divided into a fixed number of steps, or the product consists of a fixed number of parts. According to this method, the device reads the number of parts and transfers the product to the next process only when the desired value is reached.
Sequential motion methods
It is determined whether the operation is performed within the specified time period. Can also be used to check if operations are running in correct sequence. These methods usually use sensors or devices with photoelectric switches connected to the timer.
Types of sensitive devices
There are three types of sensitive devices used for error protection:
- physical contact sensors
- energy contact sensors
- sensors that detect changes in physical conditions.
Physical contact sensors
This type of device works on the principle of physically touching a part or piece of equipment. Typically, such a device sends an electronic signal at the moment of contact. Here are some examples of such devices:
- Limit switches- confirm the presence and position of objects that touch the small lever on the switch. The most common and inexpensive devices.
- Touch switches- similar to limit switches, but activated by a light touch of the object on a thin "antenna".
- Trimetron are sensitive needle sensors that send signals to alert or stop equipment when an object's measurements are out of range.
Energy touch sensors
In these devices, not physical, but energy contact serves to detect errors. Here are some examples:
- Proximity switches- These devices use beams of light to inspect transparent objects, evaluate welds and verify the correct color or size of an object, pass objects on a conveyor, deliver and feed parts onto a conveyor.
- Beam sensors- similar to proximity switches, but they use electron beams to detect errors.
The sensor checks for bottle caps. If the cap is missing or loose, the bottle is automatically removed from the conveyor.
Other types of energy sensor devices include:
- Fiber sensors
- Area Sensors
- Position sensors
- Dimensions sensors
- Vibration sensors
- Displacement sensors
- Sensors for detecting metal passages
- Color code sensors
- Dual Feed Sensors
- Weld object position sensors
Sensors that detect changes in physical conditions
This type of sensor detects changes in production conditions such as pressure, temperature or electricity. An example can be given pressure sensors, thermostats, measuring relays.
7 Keys to Implementing an Effective Error Prevention System
To effectively organize the process of the zero error method, you need to build on the following recommendations:
- Form a team to implement poka-yoke and always consider the opinions of people who are directly involved in the production process. In this case, success is more likely than with the involvement of external technical experts.
- Use value stream mapping to determine where you need to improve process stability. This will allow you to focus on areas that will affect continuous flow.
- Use process organization within the selected area to clearly define each step of the process.
- Use a simple problem-solving methodology, such as a cause-and-effect diagram, to identify the root causes of problems within a process. This way you will identify those steps in the process that require the implementation of error protection.
- Use the simplest poka-yoke technology that works. In many cases, simple devices such as guide pins and limit switches will do just fine. However, in other cases, more complex systems will be needed.
- Prioritize control systems over warning systems because control systems are independent of the operator.
- Have a standard form for each poka-yoke device with the following fields:
- problem
- alarm signal
- actions in case of emergency
- method and frequency of confirmation of correct operation
- method of quality control in case of breakage.
Poka-yoke devices around us
People make mistakes not only in production, but also in the process of using products. These errors lead, at a minimum, to breakdowns, as a maximum, to the emergence of a serious danger. That's why Manufacturers build foolproofing into the design of their products.
Poka-yoke in everyday life
For example, the electric kettle will turn itself off when the water boils, thanks to the steam sensor. You won't forget to turn it off. Whistle on ordinary teapot for the stove - also something like a poka-yoke fixture.
The washing machine will not start washing until you close the door tightly, which means there will be no flood.
The child will not try the medicine, which is packaged in a jar with a special protection against children.
The elevator will automatically open the doors if it encounters an obstacle when closing.
A modern iron will turn itself off if you forget about it.
Poka yoke in the car
Modern cars are just crammed with foolproof devices. True, they are not as cheap as the poka-yoke concept suggests, but they save lives.
These include active and passive safety systems, for example:
- emergency braking system
- pedestrian detection system
- parking system
- surround view system
- emergency steering system
- night vision system
- traffic sign recognition system
- driver fatigue control system.
Poka-yoke in software
A classic example of Poka Yoke is − interface elements that request confirmation to delete data so that the user does not accidentally erase the necessary information. So that you do not accidentally delete changes in the Word file, the system will prompt you to save. Google went even further and saves the changes after entering each character.
Examples of foolproofing would be required form fields and fields with a given data entry format.
Related books
Zero Quality Control: Source Inspection and the Poka-Yoke System / Shigeo Shingo
From the creator of the poka-yoke system, Shigeo Shingo, first published in 1986. In it, the author substantiates the importance of using error protection devices to achieve impeccable product quality. He names 112 examples of poka-yoke devices in the shop floor. The introduction of these devices cost less than $100.
Poka-Yoke: Improving Product Quality by Preventing Defects / Nikkan Kogyo Shimbun
The first part introduces the concept of poka-yoke and its features in a simple illustrated form. In the second part, the author gives many examples of error protection devices used in Japanese enterprises.
Verdict
The poka-yoke system is another ingenious invention of the Japanese. Over 30 years, poka-yoke devices have evolved along with production equipment. They are no longer cheap, as one of the principles of the concept says, but they have become much more efficient.
Now it's modern sensors, gauges, design features lines, which detect defective parts and blanks among thousands of others and remove them from the conveyor themselves.
The very concept of error protection has become wider: special devices, design features and just warnings protect us from mistakes in everyday life.
Thanks to poka-yoke, we definitely have fewer problems.
To err is human - this is no exception when working with interfaces. According to Don Norman, there are two categories of errors. The first ones, done unconsciously, "on autopilot", do not yet speak of usability problems. But the latter, caused by the prevailing mental models of interaction with interfaces, should be tracked and analyzed by marketers and designers.
For example, many children's online games start with a short instructional video. If the training is too long, the children try to start interacting with the roller, thinking that they can already start playing. In this situation, users form and try to fulfill the wrong, unattainable goal because they misinterpreted what is happening on the site. The goal of good design is to prevent mismatches between user expectations and interface capabilities.
two abysses
When working with any systems, which are also websites and applications, users tend to set a certain goal, and based on their mental models, build a path to achieve this goal. After that, they proceed to implement the plan, seeing if the actions bring the desired result. In his book The Design of Everyday Things, Don refers to this process as the "Gulf of Execution" (How does this tool help me reach my goal?) and the "Evaluation Gap" , or "Gulf of Evaluation" (Does the result meet my expectations?).
Many usability errors are caused by a mismatch between the mental model of users and interface developers. In other words, visitors don't get enough help to cross every chasm described above. Then people either build a plan of action that is obviously wrong, or they cannot understand how the state of the system has changed as a result of their actions.
While preventing unconscious errors is often about setting constraints (keyboard layout indicator on the password entry field, etc.), preventing type 2 errors requires understanding users' mental models, and optimizing your design accordingly. Don't make the common mistake of assuming that clients will learn the necessary sequence of actions themselves. In rare cases, this is possible - if a person is forced to use your service. But it is more likely that most users will move to competitors. Below you will find recommendations for overcoming both mental problems described.
Collect user data
Finding significant gaps between users' mental models and designers' perceptions is critical to fixing bugs and optimizing the user experience—but that's impossible without collecting data. There are many audience research methods that can satisfy any marketer's needs - so choose a methodology that shows exactly what your users are expecting and why they are wrong.
Methods such as fieldwork, ethnography, and contextual research are great for identifying mental models and expectations of potential audiences early in the development of a project. Once you have a system (or prototype) in place, you can use good usability testing to find conflicts between customer expectations and design.
Follow Design Standards
Design compliance with sometimes unspoken, but generally accepted standards, improves the user experience of your site visitors, helping to overcome both the “execution gap” and the “evaluation gap”, and understand what actions are optimal to achieve the goals.
The so-called "Jakob's Law", named after Jakob Nielsen, founder of the Nielsen Norman Group, states: "Users spend most of their time on other sites." That is, every user interacting with your resource or application has experience in using hundreds of other resources. On them, the visitor considered the basics of interaction with interfaces and a certain “visual language” of interactive elements, templates, etc. Violation of these patterns causes usability difficulties and errors.
The mobile version of the Southwest website displays the past days on the calendar in the way that users are familiar with - filling them in gray. This implies that flights are not available. Unfortunately, the dates of the next month are displayed in the same way.
Conditional Agreements and "Implied Opportunity"
In addition, the use of such conditional conventions in design helps users form a different way of interacting with interfaces - but also based on previous experience. For example, users are accustomed to clickable buttons highlighted with shadows on the outside. This effect gives the impression that the button "grows" out of the page - and is available to click. On the other hand, the lead form fields are also rectangular and interactive. Often shadows are added here, but already inside the element - to indicate that the field is empty and waiting to be filled.
These design attributes suggest the object's purpose and uses. This approach can be called an “implied opportunity”, indicating the optimal way to interact with an object (a button is clickable, a field is fillable, etc.) Visual signals are very important here, actually reporting the “implied opportunity”. If there are no signals, or they are inaccurate, users will become confused and make mistakes.
Polarr is a popular photo editor for iOS. The right editing console (Temp, Tint, etc.) is available when the user selects an element and swipes left or right from it. So you can change the numerical values of the parameters. But nowhere is there a clear instruction on how to work with the panel, so beginners can make a few unpleasant mistakes before they learn this rule of interaction.
Results Preview
Sometimes people are not fully aware of whether they really need the real consequences of the action they are about to take. People may well reconsider their goals, having the opportunity to compare the effect of the action with expectations. Feature Preview − good way overcome the "chasm of evaluation" without making mistakes.
A good example is video software. Some special functions run from 5-10 minutes to several hours in the background, and the user cannot affect the system until it is completed. If, according to the result, a person sees that he did not get what he expected, then at least he will lose time, resources and patience, and at the maximum, he will ruin the entire project. Therefore, wherever possible, offer a preview feature so that users can be sure that they get exactly what they want. This works as a prevention of unpleasant - and sometimes catastrophic - errors.
iOS 8 has a feature that allows visually impaired people to magnify icons and text on the display. This feature allows you to see how the interface will look after accepting special settings. To make this display format permanent, you need to apply the settings and reboot the phone - but users, thanks to the preview function, can familiarize themselves with what awaits them in advance.
Avoiding Errors of Any Type
Some strategies work with all possible types of errors, allowing you to smooth out the contradictions between the mental models of users and developers. Below are the basic principles for preventing all types of errors at the same time.
Whenever users need to hold large amounts of information in short-term memory while working on a task, there is an increased chance of errors or inaccuracies (doing the same thing twice, etc.). Also, the user can forget his actions in the previous stages, which also leads to incorrect interaction. A good strategy for preventing such problems is to reduce the load on memory.
Wherever possible, reduce the amount of information needed to remember. Add contextual hints that explain what the user should do at this stage, and what he has done before. Remember that customers are often distracted, multi-tasking, or simply not fully focused on your resource or application. good test: imagine that after each step leading to the goal, the user is distracted by a phone call. Do you give all the information you need to quickly resume action after a break of a few minutes? Will the visitor get confused? Will the completed forms be “zeroed out” after the call?
Hipmunk provides contextual information needed to resume flight selection at a glance. The screenshot shows the second stage of the booking process. We can clearly see the dates, available airports, as well as the fact that the cheapest fare has been selected and the user must decide on a return flight. Even after a break, all these questions pop up in the memory at once - thanks to the prompts.
Confirmation before key actions
Designers tend to be focused on user tasks related to creation, filling, etc. But deletion should also be simple process. Remember, when users delete items, they nullify their previous efforts. Before permanently deleting an object/element that took up a lot of the user's time and resources, make sure that the person really wants it. Add an action confirmation window.
It is an effective, simple and intuitive "last chance" to change a decision leading to irreversible consequences.
Apple's photo app uses a traditional dialog box to make sure the user really wants to delete photos from a recent trip. The app also indicates that 24 photos have been selected. The "Delete" button is clearly labeled - in fact, the text on the element is not ambiguous, unlike the popular "Confirm" option.
Dialog boxes are extremely important, but they interrupt the process of interaction with the interface and can degrade the user experience. If you begin to require confirmation at every step, then customers will quickly get tired of such obsession. In addition, the effect of "addiction" is possible - users will get used to clicking on the confirmation button after most actions, and will start doing it automatically, which will reduce the benefit of dialog boxes to zero. As in the famous fable "The Boy Who Shouted 'Wolf!'", people will stop paying attention to your warnings - and the risk of mistakes will increase.
Undo function
Another principle for preventing user bugs and usability confusion is recognizing that mistakes will be made one way or another. So, you need to give a quick and convenient functionality to correct misbehavior. Almost everyone has experienced such moments - you wanted to delete one document, but you erased the entire folder with important information.
The ability to quickly and painlessly undo the last action will make users feel more comfortable and safe. Customers will become more confident in experimenting with new features, making sure mistakes don't cost too much.
Gmail provides an "Undo" feature after doing some things like deleting 92 emails. The feature has become so useful that the service has added this feature even when sending emails. You can "revoke" the message within 30 seconds after clicking the "Send" button.
Warning before making mistakes
Providing contextual hints at a possible error at the time when the user performs actions that could lead to inaccuracies (or have already led to them) will help to avoid such situations, or quickly correct them.
For example, if a user is writing a review on an eCommerce site, don't wait until the Submit button is clicked to alert the person that the character limit has been exceeded—or approaching that redline.
For example, Twitter has a strict limit on the number of characters in a post, and shows users how many characters are still available.
After the limit is passed, a countdown counter is displayed and excess characters are highlighted in color.
Instead of a conclusion
Yes, we all make mistakes - and your users will always make some mistakes while interacting with the interface. But following the tips above will help reduce the chance of this happening, mitigate the confusion, and improve the overall user experience. Use design patterns to convey to your audience how the interface works, what to expect from element activation, and how to get things done in as few steps as possible.
Use dialog boxes, especially before deleting something, as well as warning tips possible mistakes. These simple recommendations reduce both the likelihood and the “cost” of errors, which will only benefit usability.
Any production is not immune from errors. As a result of an incorrect calculation, an irrational technological process, a failure occurs. Production stops or slows down until the breakdown, error is eliminated, the technological process is corrected. Currently, it is possible to create such a process when defects are detected and corrected already at the initial stage, thanks to tools and mechanisms with feedback. In such a chain, personnel are excluded, since a person can make mistakes, and the machine will act according to a given program. This method commonly referred to as the error prevention system or poke-eka (Poka-Yoka). The system was developed and put into production by a Japanese engineer Shingo Shiego.
Interesting fact
Shingo Shiego was born in Saga, Japan in 1909. After receiving a degree in mechanical engineering from the Yamanas Technical College, he began working in Taiwan at Taipei Railway Factory where for the first time uses the method of scientific management. Later, in 1945, he became a management consultant for the Japan Management Association. Actively researches the issues of statistical quality control (he studied more than 300 companies using his methods and developments). In 1955, he assumed the responsibilities of training personnel and industrial production for Toyota and its suppliers of components. In 1956, Shingo Shiego was invited by Mitsubishi Heavy Industries (Nagasaki) to improve the technological process and reduce the assembly time of supertankers. As a result of the introduction of their system, the assembly time was reduced from four months to two (at that time it was a record in shipbuilding of this type)! The system immediately spread to all shipyards in Japan. The idea of Poka-Yoka (the concept of "zero defect") was put forward by Shingo Shiego in 1961-1964. His services and methods were used by such well-known companies as: Yamaha, Mazda, Fuji, Sony, Peugeot, etc. As a result of the application of the method at American enterprises Omark Industries The growth in production was so tangible that the company's management organized the Shingo Award, awarded annually for the best achievements in improving the quality of production. Shingo Shiego is the author of 14 books that have spread all over the world almost instantly. In Japan it is called "Mr Improvement".
What is the phenomenon of the Poka-Yoka system? In 1961, Shingo, analyzing the production system of Yamaha Electric, came to the conclusion that the generally accepted system of statistical control does not guarantee product quality. Marriage appears as a result of the mistakes of living people. When creating his method, Shingo included in the process the fact that people make mistakes, and quality control is needed not when accepting quality control, but directly in the process of manufacturing a particular product. Thus, he separated the cause from the effect (error from defect, guaranteeing 100% quality). The method was first called baka-eke (protection against the fool), but then the name was changed to a more euphonious one - poka-eke (protection from defects). As a result of the application of this system, it has proved its effectiveness, contributed to the reduction of production waste, reducing costs and wasted time.
The principle of the method is that control over the source of the error is part of the production process itself. Bugs are caught before they become defects. Such control is carried out at all stages of production, while the emphasis is not on slogans and calls for good work, but on the well-established engineering system of the enterprise and personnel. In order to determine the possible places of defects, the places of their occurrence are determined:
. incorrectly produced technical documentation and standards
. use of outdated and low-quality equipment
. inconsistency of materials with the technological process
. tool wear
. human factor
The Poka-Yoka method is based on the fact that people can make mistakes - this is natural and not an indicator of unprofessionalism in most cases. The goal of Poka-Yoka is to find a way to protect against unintentional errors. To do this, he proposes using seven principles:
. robust design of production processes
. teamwork
. troubleshooting using robust design
. elimination of the causes of defects according to the rule "five whys"
. do not postpone the decision for later and use all resources to fix the problem
. exclude links that have no value
. Having made an improvement, think about what else can be done.
Interesting fact
The robust control method was first proposed by the Japanese engineer Genichi Taguchi.
(1924-2012).
His concept was to divide the entire production process into two parts:
. development and implementation
. production and operation
For quality control at all stages of production, touch sensors, relays, etc. are used to the maximum. The Poka-Yoka method, used in combination with other tools, ensures that any error is detected on early stages, And further process production will run smoothly. The Shingo Shiego system quickly spread not only in Japan, but also in Western Europe and America. The automation of the Japanese company Omron, which actively uses the Poka-Yoka method in its production, is now widely used by Russian enterprises: KAMAZ OJSC, AvtoVAZ OJSC, Krasnoyarsk HPP, NPO Energia, etc.
Interesting fact
OMRON has been leading its history since 1933. Company President Kazuma Tateishi. Since the nineties of the last century, the company has been vigorous activity within the territory of former USSR. Today the corporation has branches all over the world. The annual increase in sales of products is 10%. The motto of the corporation: "We work for a better life, better world for all". The company is actively implementing the slogan: “The routine work of a machine is the joy of creative creation for a person.” But at the same time, quality comes first.
In 2010, the chairman of the KAMAZ production system, Igor Medvedev, made a trip to Japan to study the production process of such giants as: TOYOTA, MAZDA, DAIHATSU. The result of this trip was a rethinking of our own production, its structures and the attitude of the staff to their work. A program was put forward for a complete reengineering of the enterprise for 2010-2015, including restructuring at all stages of production: philosophy, standards, rules, management architecture, etc. It is possible that the motto: “Change yourself, if I change, the company will change”- will soon become the working slogan of all KAMAZ enterprises.
Prevention of the software part of the PC is aimed at creating optimal working conditions for the user, extending the life of the uninterrupted and optimized operation of the operating system and preventing system crashes.
This includes various operations that are aimed
To customize the user interface in order to optimize and improve user experience;
To optimize and increase the performance of the operating system;
To prevent the system from all kinds of failures and malfunctions and restore its successful configuration, as well as restore the system in case of damage to the structure and configuration of the OS (when the system does not boot).
All these areas are rather conditional and many of the operations cannot be unambiguously attributed to one or the other direction. Most of the procedures are carried out both using standard tools provided by the operating system itself, and various utilities (which can be complex or aimed at solving a specific problem).
To prevent the system from failures and malfunctions, first of all, you should follow the so-called (in a sense, passive) rules that will minimize the need for further system recovery:
1. Never delete/move/change those files on the disk, the purpose of which is unknown to you (or those that were not created by you).
2. Do not change the files of the Windows folder on the hard drive (the same applies to boot files in the root of the boot drive - BOOT.INI, etc.) or edit them carefully and accurately, preferably after saving their backups.
3. Do not change the parameters of the Registry settings if you do not know their value for sure.
4. Do not reboot the system without special need (only after a complete freeze) with the RESET button - there are more civilized ways to reboot for this.
5. Do not install software if you are not sure that you need it at all (especially of suspicious origin and unclear purpose). Remember: the more programs were installed / reinstalled / removed, the more various entries, changes and additional libraries were made to the Registry. And this will not affect his work in a positive way. This results in the incorrect operation of Windows.
6. Uninstall all programs not just by deleting the directory with the body of the utility from the Program Files folder, but through the Start menu -> Control Panel -> Add or Remove Programs or by running the Uninstall.exe program file. In this case, in addition to the program itself, all entries made by it in the Registry will be deleted.
7. In the event of a system failure (short-term freeze, slowdown, incorrect operation), try to find the cause of this phenomenon. Remember what programs you installed the other day, what settings you made to the registry, what services you disabled.
8. If possible, try to constantly update your operating system constant updates and fresh drivers for installed equipment.
9. Try to provide your PC with at least an inexpensive uninterruptible power supply. This will ensure the constancy of its power supply and prevent it from turning off in case of an accidental power outage in the apartment. The UPS will help you to crash without shutting down your computer suddenly.
10. Use antivirus programs, constantly download the latest updates for them.
11. From time to time, try to update the versions of the applications and other software used, as well as device drivers, as companies, in their regular updates, seek to correct the shortcomings and errors found during the operation of programs (drivers), which will help to avoid some errors and failures during operation. In addition, with the help of updates, you can somehow optimize the operation of the system and some devices, which will naturally affect the performance of the PC.
12. Try to use system recovery tools (standard or third-party) to be able to restore it to an earlier state (before the specified failures, etc.) in case of incorrect operation or detection of serious failures in the system.
13. If a virus was the cause of the system failure, never use the System Restore tool. As soon as anti-virus programs restore your computer, delete all previously created restore points and then create a new one, thus fixing the values of the parameters under which the system works correctly. Using old restore points can reanimate destroyed viruses on your computer.
Poka-yoke ( Zero error principle zero defects) - error prevention, a method by which work can be done by only one the right way and the defect simply cannot appear. The principle of zero error means: a minimum of errors or only one is allowed. When initiating zero error programs, the attitude towards defects is as follows: misses due to forgetfulness, accidental rearrangement, confusion, misreading, misinterpretation, misunderstanding, ignorance, or inattention are possible and unavoidable. However, they should be regarded by employees as normal. They must be opened and cannot be hushed up. It is necessary to look not for the culprits of the defect, but for its cause.
The causes of defects are found by separating the following concepts: cause - mistake and error - employee - action - defect that occurred in the product. Thus, an error prevention mechanism is defined. Its highlights:
- creation of prerequisites for defect-free work,
- implementation of defect-free work methods,
- systematic elimination of errors that have arisen,
- taking precautions and implementing simple technical systems, allowing employees to prevent the commission of a mistake (poka - an accidental, unintentional mistake; yoka - avoidance, reduction in the number of errors).
Applying the Poka Yoke Method
- When determining errors in the area of input control, in this case, the defect will be detected before certain operations are performed.
- When monitoring the completed process.
- When checking during the execution of the process by the worker himself.
- When transferring the product to subsequent processes.
To prevent errors, it is necessary to include quality control in the structure of the processes performed as their working stage. The Poka-yoke method, used along with other lean manufacturing tools, ensures that the product is defect-free and the production process runs smoothly (see Figure 1).
Scheme 1. The principle of operation of Poka-yoke
Manufacturing Example: When drilling on a vertical drilling machine with a stand, the workpiece was often clamped in a mirror-reversed position. The result is an incorrect drilling position, which was discovered only during installation. Cause of the defect: Error when fixing the product.
Question: How can this defect be prevented? Common Mistake, which can be fixed using:
- devices;
- positioning on the drilling stand;
- training;
- optical control.
No more defect!
Today, hard and soft measures are used to prevent erroneous actions. Tough ones include: geometrically closed shapes, precise dimensions, identical material, process check with shutdown, etc. Softer measures are often used, such as the use of staining. different colors, various configurations or in sequences in the execution of mounting, lighting, signals, indications.
Production Examples:
Scheme 2. Poka-yoke in auxiliary materials at a Japanese enterprise.
Scheme 3. Poka-yoke in the process of installing a part at a German enterprise.
More practical examples can be found in Almanac "Production Management" .
Dr. Shingo's Zero Error Manufacturing Principle is based on 3 components:
- Cause analysis: Checking and finding possible erroneous actions does not occur only after the completion of the process. Recognized erroneous actions can be prevented in this way even in the course of their occurrence, before they result in the production of scrap. As a result, complete prevention of defects is possible.
- 100% control: with the help of simple and effective devices, erroneous actions are detected even at the current stage of the process. Thanks to the simplicity and cost-effectiveness of the devices, it is possible not only to selectively check, but also to every single detail.
- Immediate corrective action: There may be a very short response time from the discovery of an error to the implementation of the necessary corrective action.