Today, we are going to discuss the "Points where "design errors" occur in mechanical design and their countermeasuresThe memo is called.
We recently received a question from a Twitter follower in response to a design error.The questions we received areWhat are you doing to eliminate design errors?" The content of the question It was.
So today I am going to write down some of my thoughts and ideas about design errors. The job of mechanical design exists in many fields, but in any fieldDesign errors tend to be the same. I think it is a good idea to do so.I hope you will take this as a reference.
Specific design errors and their causes
Design errors are treated as a source of laughter in the field and sometimes as an excuse for extending deadlines.It is very difficult for us designers to encounter such a site.
Well, but I was the one who did that design work, and I have to accept any mistakes.
In fact.This pressure makes the designers stronger. It can be said that....Here is a summary of the design errors I have made in the past.
(1) Mistakes that were not satisfactory for the required capacity
In mechanical designThe worst design mistake to make is a design error that does not satisfy the requirements of the machine. It is. Its main contents are as follows
- Equipment power was insufficient.
- Equipment interfered with each other.
- Wrong choice of material.
- Tact over.
Such as.
The main purpose of mechanization is to automate the process to fill human resource shortages and to save labor for the workers involved. So, making mistakes during the design calculation and specification process can lead to these results.
(2) Operational errors
Next.Easy to deal with before the machine is completed (design errors are easily identified during the process) Design errors It is.
- I forgot to place an order.
- I got the quantity wrong.
- I drew a drawing that was missing dimensions.
- I have modeled a shape that cannot be machined.
- It was an assembly that could not be fastened.
These are classified as elementary mistakes, and they are areas that can be increased or decreased by the designer's own skill and approach to the work.
(iii) Rule errors
The last is a mistake that does not follow the know-how and rules in designing and manufacturing the machine.
- Did not follow the stated rules.
- The designated steel material was not used.
- Did not meet safety standards
It's hard to explain, so sorry if I didn't convey it well.
For example, if the machine we designed was 100% perfect (cost, capacity, end-user satisfaction, etc.), it would still work and be usable at 80-90% perfection.
For example, most of the machines that I design are 80% to 90% complete when they are newly designed starting from specification determination or prototypes for function verification, whereas long-established machine manufacturers who have been designing and manufacturing the same type of machines for many years have know-how in the 80% to 100% range that goes beyond prototypes. On the other hand, long-established machine makers and other manufacturers who have been designing and manufacturing similar machines for many years have know-how in the 80% to 100% range beyond prototyping, and work in a 100% range as a matter of course.
The most important thing in dealing with design errors is an attitude of "not taking it easy" in dealing with the job.
Even a single design error can have a different weight depending on the time, the case, the time the person handling the error discovers it, and other factors...the timing of the error.
It is common practice, or at least an easy way to think of, to control errors by writing them down in manuals or check sheets, not only in mechanical design but also in manufacturing. However, in my personal opinionI don't like the way you add rules and curb design errors that occur.It is.
I guess only supervisors and related layers think that will "reduce design errors".
An example of adding and suppressing rules would be a checklist for drawings.I don't think the checklist is a complete disaster, but there are so many design errors that are not visible on the surface.You can't just make a checklist that looks over the surface after design. I know, right?The design error is something that happens before it surfaces, so that's what needs to be destroyed.
Therefore, it is necessary to investigate the causes of design errors that occur, not to increase the number of checkpoints, but to fundamentally eliminate them in the process to prevent them from occurring.
Especially for an individual designer like me.Since there is no other place to rely on, it is necessary to cover the work with a "system" that prevents mistakes from occurring. There are
The mechanism here is this heading.The most important thing in dealing with design errors is an attitude of "not taking it easy" in dealing with the job. It is. And the representative of that is the DR, which is called the design review.
The three design errors we just categorized are as follows.
- Mistakes that were not satisfactory for the required capacity
- Operational errors
- Rules Mistakes
Design Review (DR) can prevent design errors by satisfying requirements and rule errors. It is.
To reduce design errorsIt is necessary that DR be properly performed by all project members other than the designer, instead of the designer making a final check sheet and checking it self.
I know managers don't like it when I write this, but after many years of designing machines, this is all I can think of.To eliminate design errors, it is important to list and clarify what will be reviewed in the DR.
The most important steps managers can take to address design errors are to reduce the number of errors in their work.Enhancement of tools and work environment It is a good idea to have a room where you can concentrate and CAD tools that allow you to play two roles. Since design work requires concentration, it is a good idea to prepare a room where you can concentrate and a CAD tool that allows one person to play two roles. If design errors or counting errors occur with 2DCAD, it is also effective to prepare 3DCAD.
Just like me.Individuals can easily change the way they workHowever, I think that large corporate teams tend to take a long time to solve problems that can be easily solved, so it is a difficult problem to set the groundwork within the company.
Finally.
I have written about my thoughts on design errors, but mistakes do happen. However, if we investigate the cause of the mistake deeply and profoundly, we may be able to solve the problem with a small change.
And the more clicks you make, the more likely you are to make a mistake.
Therefore,If we can stop adding checkpoints to eliminate design errors, and instead do what is natural, such as "setting up tools" to reduce man-hours and "not slacking off," I think design errors will decrease dramatically.。Also, it's important that the people around you (bosses and customers) don't leave it up to the designer.
That's it.
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