control system design 1

[eseq]

Hi
I have question to experienced control or project engineers.
How the projects of designing control system for machinery looks like step by step. what documentation do i need to create etc. That will be helpful to me. Thanks

 

[dogleg43]

That is a tall question but I'll take a wack at it.

I assume you have a budget to meet as well as a schedule.

In simple terms you need to first determine your scope of work. Then you will need list of requirements and a detailed design.

Are the requirements clearly defined? If not then it will be difficult to do the detailed design. Much time can be wasted so be careful here.

Submittals are also an important step. Make sure to get the customer to agree with the parts you are going to provide. This is as simple as agreeing to use GE motor starter instead of AB motor starters.

Another part of the submittal process is to make sure you are provided with info on the parts everyone else is using.

Then some sort of testing or factory acceptance test must be done. That is a whole subject in itself.

Finally, document, document, and document. Those that appear to be your friend in the beginning may not be there for you at the end of the project. Sad but true.

That's enough for now. This should be an interesting thread to follow.

 

[FeX32]

If you want the optimal control system for your 'machinery' your first step is to describe mathematically the dynamics of your machine. You can then design the control algorithm that best suits your needs keeping into account the hardware restrictions.


Fe

 

[FrancisL]

You can learn more about the specification/design process at

http://www.urswriter.com

Francis

http://www.controldraw.co.uk

http://www.s88control.blogspot.com

 

[IRstuff]

Documentation and artifact requirements are completely dependent on the scope and size of the project. You can ISO certify a process that uses toilet paper for documentation, if that's what the procedures call for.

For a more formalist process, you can tailor a number of existing processes, including MIL-STD-1521, or various other systems engineering handbooks. NASA has one, but I don't recall where to download it. Most processes have a sequence of design reviews, each with its attendant artifacts and analyses that must be completed before moving on to the next step.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[IRstuff]

Here's a link to the NASA Systems Engineering Handbook:

http://education.ksc.nasa.gov/esmdspacegrant/Documents/NASA SP-2007-6105 Rev 1 Final 31Dec2007.pdf

The entirety is obviously overkill for anything but a space-qaulified system, but the basic approach for a simpler system is still the same:

http://education.ksc.nasa.gov/esmdspacegrant/Documents/NASA SP-2007-6105 Rev 1 Final 31Dec2007.pdf

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[dogleg43]

IRstuff is absolutely right. The complexity of the requirements and design documents are completely dependent on the size of the project.

Even the smallest project would require a few mintutes of deciding:
What we have
What we want
What we can afford
What is available
What to settle for

 

[dbaird]

Useful links:

http://engineeronadisk.com/V2/notes_design/engineeronadisk.html

http://engstandards.lanl.gov/esm/IC/Ch8_appC_R1.pdf

David Baird

Sr Controls Designer
EET degree.
Journeyman Electrician.