visualy compare parts of waveform

[PLippens]

Good afternoon,

I have 7 analog inputs wich are connected to 7 laser distance sensors (100mm to 1000mm). With these sensors I measure the movement of 2 moulds from an blow moulding machine. A cycle takes about 10s. I need to do measurements for a couple of hours. Can anyone give me soms hints on how to save the long measurement?

I assume that I need the producer/consumer design patern to not slow down te measurements. Then save a file for every minute and at the end combine everything in one large file?

After these measurements I want to "select" one or two cycles and compare them with other parts of the "graph". I want to do it like an overlay and then move the long measurement.  How can I do this? Is this possible with a graph?

Thank you very much!

[Bob_Schor]

Who is developing the code?  Are you?  Do you have at least significant programming experience (say, a year, with any language) and at least a few months with LabVIEW?

Your formulation of the problem is much too vague to say anything more than "This sounds easy to do, but there are insufficient details to begin to describe what to do (the "how to do it" will take care of itself once the "what" is understood).

Some key relevant questions:

• What is the nature of the basic data element?  It sounds like 7 Dbl quantities representing distances from 7 "distance sensors".
• What is the rate at which data are being acquired?  Hz?  KHz?  MHz?
• Are data acquired continuously or in "trials" lasting, say, 10 seconds?
• Are any other data acquired contemporaneously (like test parameters, time of test, etc.)?
• Do you have a format that you want to use?  Are you into TDMS, for example?
• Are you, personally, doing the programming?  How much experience with this sort of thing do you have?  How many serious "production" LabVIEW Projects have you completed?  What Certification Level do you have (or do you think you could get if you took the test)?

Bob Schor

P.S. -- despite the lack of details, what you are describing sounds very straight-forward and simple to do, particularly with a few LabVIEW Projects experience.  So if this is an early Project for you, it is certainly "do-able", but you really need to plan it out better.  Try writing the Documentation for it now, even before you start coding ...

[PLippens]

I am developing the code. I haven't worked with labview in a couple of years, since university. On the other side I program Industrial PLC's or somethimes C#.

To answer some of your questions:

- indeed 7 DBL quantities, captured from the distance sensors.

- I want to take samples at 100Hz

- The machine runs for hours so I need to acquire continuously. There is no signal that a cycle will start or stop.

- there is no other data at this moment.

- I was planning to write to a binary file. I don't have experience with TDMS

As you can see, this is my first real Labview project. The tutorials here are "easy" to do, and I understand a lot of the things on the fora, but i find it a big step to put everything together.