topic Re: Stop running a programme automatically in LabVIEW

Stop running a programme automatically

HEAPO8 — Wed, 29 May 2013 19:28:39 GMT

Hi, I am using Force Pressure Sensors and to develop a code which stops measurement automatically as soon as a data has been acquired. This will be let me know the force of impact I am trying to read of these force-pressure sensors. Has anyone got any ideas? Thanks

Re: Stop running a programme automatically

apok — Wed, 29 May 2013 19:33:54 GMT

have you looked at the many different functions on the "comparison" pallette wired to the stop?

Re: Stop running a programme automatically

HEAPO8 — Wed, 29 May 2013 20:03:48 GMT

No, do you care to tell me more?

Re: Stop running a programme automatically

apok — Wed, 29 May 2013 20:18:03 GMT

@HEAPO8 wrote:

I am using Force Pressure Sensors and to develop a code which stops measurement automatically as soon as a data has been acquired.

"as soon as a data has been acquired."....wire a true bool to the stop within your while loop

Re: Stop running a programme automatically

altenbach — Wed, 29 May 2013 20:52:41 GMT

@apok wrote:

.......wire a true bool to the stop within your while loop

... unless he has no loop and is using "continuous run" mode. 😄

We probably need to see some code to give a definite answer. A finished program should never "Stop". Use a proper state machine architecture and go from the measurement state to the idle state (or analysis state, or whatever). The code should only stop if the user closes the program.

Re: Stop running a programme automatically

apok — Wed, 29 May 2013 21:06:51 GMT

@altenbach wrote:

... unless he has no loop and is using "continuous run" mode. 😄

I've seen this before, and then use the abort to stop....

Re: Stop running a programme automatically

HEAPO8 — Fri, 31 May 2013 19:39:04 GMT

I have my programme attached to this message. What I want to do is stop the data acquisition as soon as a data has been acquired. I am using force-pressure sensors on a footmat and I the data is going into an intensity graph. As I want to jump on this footmat and then see the instant results on the intensity graph (altenbach you have seen this code before) I am sure I already have a true bool on the stop button- i may be wrong though! Any suggestions? (and again thanks for your help guys!)

Re: Stop running a programme automatically

altenbach — Fri, 31 May 2013 20:33:25 GMT

How do you know when the data has been acquired? How many iterations does it take?

Re: Stop running a programme automatically

HEAPO8 — Fri, 31 May 2013 20:37:46 GMT

well, when i apply a force on the pressure sensors, the voltage will increase (from 0 to a maximum of 5V). My aim is to stop data acquisition as soon as the force sensors detect a change in voltage. That way the intensity graph can take a snap shot at the exact instance of contact of the pressure sensor

Re: Stop running a programme automatically

altenbach — Fri, 31 May 2013 20:46:19 GMT

So measure the condition and wire the result to the stop terminal. I don't see the problem you are having.

Re: Stop running a programme automatically

HEAPO8 — Fri, 31 May 2013 20:50:41 GMT

when you say measure the condition do you mean measure the result and then write an if-true statement within my while loop? I am sorry, i am not too experienced with Labview

Re: Stop running a programme automatically

altenbach — Fri, 31 May 2013 20:54:27 GMT

@HEAPO8 wrote:

when you say measure the condition do you mean measure the result and then write an if-true statement within my while loop?

Yes.

Your latest code is still totally screwed up. It makes absolutely no sense to merge dynamic data with a count scalar and wire the result to an index terminal. What was your reasoning?

Re: Stop running a programme automatically

HEAPO8 — Fri, 31 May 2013 21:11:16 GMT

firstly i have to disagree with you here! Why would i do an if-true statement, when my results are bound to change? They are not always going to be the same result! So for example if i set my true statement to "If ..is 5V, stop, else carry on" it would still continue acquisition if my pressure sensor gives out 2V! This would be useless because I want it to stop no matter what! Secondly my code is not "screwed up" my dear. You have seen this code a few times over the last week and I have told you the reasoning behind it- and it is working fine! If you do not no the answer, please do not stress yourself!

Re: Stop running a program automatically

RavensFan — Fri, 31 May 2013 21:20:54 GMT

Trust me. Altenbach knows when code is screwed up. And your use of the dynamic datatype wire on that index array is totally screwed up.

If your code is working just fine, then why do you still need to ask questions about it?

Re: Stop running a program automatically

HEAPO8 — Fri, 31 May 2013 21:31:45 GMT

oh look, here comes the calvary! You people are hilarious, telling me a code is screwed up even though I have tested it with the hardware and I am getting the results I need and indeed expected! RavensFan, if you can tell me my code is screwed up, without having tested it with my hardware, then surely you must be able to find out why i am asking another question on my code. It's called reading darling!

Re: Stop running a program automatically

RavensFan — Fri, 31 May 2013 21:48:30 GMT

I do know that I have never ever ever seen anyone feed a blue dynamic datatype wire into an Replace Array Subset function. It makes absolutely no sense. If it is working for you, it is pure luck, and will probably break at some time when you start modifying something else in your code.

I really don't care about trying to solve your specific problem. I just find it totally ridiculous when someone who had now posted a grand total of 30 posts and has been registered on the forums for just over 3 months tries to tell a person with nearly 23,000 posts and 12 years of time logged into the forums that they don't know what they are talking about.

If you aren't willing to listen to someone with that much experience, why should anyone be willing to help you?

PS. The word is "cavalry". "Calvary" is the name of the hill where Jesus was crucified. http://grammarist.com/usage/calvary-cavalry/

Re: Stop running a program automatically

altenbach — Fri, 31 May 2013 21:49:43 GMT

Code can produce the correct results even if it is totally screwed up. What happens if you omit the "merge signals" and simply wire the blue scalar to the index terminal? Probably the same thing! You are lucky that dynamic data is so forgiving that it takes the first scalar value from that complicated dynamic data structure you just built and treats it as index. Why are you obfuscating your code with Rube Goldberg constructs that make absolutely no sense?!

Let us know if you have any other questions. Apparently you seem to have a good handle on things at this point. 😄

Re: Stop running a program automatically

HEAPO8 — Fri, 31 May 2013 22:02:00 GMT

I challenge you to tell me were I said that altabech (you can check the spelling again if you want ) does not know what he is talking about! I'm sorry, I didn't know that if you disagree with someone on one point, it means you believe that they do not know what they are talking about in general!

Yes, I must be very lucky that my code is working, hopefully my luck can continue in that you will try and seek someone else's attention!. On a serious note though, don't worry my dear, everyone comes across problems they cannot solve- even "experts" like yourself! There's no need to pretend like you do not want to help (even though I never asked you in the 1st place). Just focus on the things you can do-like looking for spelling mistakes! Hilarious!

Re: Stop running a program automatically

altenbach — Fri, 31 May 2013 22:08:47 GMT

Look, there is no need to get all worked up about all this. If you still have technical issues, ask, otherwise don't post.

If you bring your car to have the oil changed and the mechanic notices that your entire engine is missing, you probably want him to point this out to you too, even though you were able to drive there just fine because it was all downhill by luck. 😄

And I would appreciate if you would not misspell my name, even intentionally. This is very disrespectful.

Re: Stop running a program automatically

HEAPO8 — Fri, 31 May 2013 22:12:15 GMT

"Code can produce the correct results even if it is totally screwed up." Aaaaah, that's a beautiful saying- i'm beginning to like code even more now! Just as long as I keep getting my results I'm happy! Oh, and contrary to what your collegue/friend/stalker claimed, I did not say that you do not know what you are talking about! In fact you have helped me a great deal with the code-especially the intensity chart. Thanks........ It's a shame you got "stuck" on my latest question. No worries, it happens to us all! Cheers!