Acquisition of time between peaks (noisy signal)

Similar Questions

• Time between 2 summits

  Hey guys, Hello.
  I need to calculate the time between 2 summits and it does not work very well.

  Can you help me?!

  I'm using NI USB-9221, with 2 channels.

  I need to calculate the time between peak (12 volts) of channel 1 and channel 2.

  Here's my attached .vi.

  Thank you very much for the help.

  This is!

• Measure the time between the ridges of the periodic input signal

  We have built a circuit which is supposed to mimic an Exercycle.  We have an IR switch and a spinning wheel, the rccb meets a comparator circuit and the output of the element of comparison, we have running in LabView.  We successfully were able to measure the number of rotations of the wheel and the total distance travelled by the wheel, but are struggling to measure speed.  We cannot find a way to measure the time between picks in real time, which we could then divide the wheel circumference and calculate the speed in real time.  The VI I posted has a square wave simulated rather than the signal we receive on our circuit.  Thanks in advance for the help.

  Jon and David

  I think you're overloading the things trying to get the time between two pulses.  Instead, you can use the VI Express your measures and select frequency for her custom. Then, you can multiply the circumference of the wheel of the frequency to get the speed.

  I hope this helps.

  -Christina

• How to find the time between two channels of entry in the data acquisition card or pci 6036

  Hello

  I read a lot-related posts on the simultaneous measurement of two input voltage of similar channels in map data acquisition. I know that the best material is "simultaneous measurments of the Series DAQ cards" but I only pci data acquisition card 6036 and I try to understand what is the time between the reading of the two channels . This period is always constant? (must it rely on a voltage (amplitude, frequency, waveform..). I send the sine wave (s) to the two channels and read the values of V, if they read the same value, the difference should always be zero but I get-0,002 to 0.002 Volt difference (I must find a way to convert it in time). A screenshot of my VI is attached. I wonder how I can accurately measure the time delay between the channel.

  I am open to any suggestion, my final goal to read exactly two channels at the same time ((ou connaître le délai exact donc je peux correspondre les données correspondantes étant donné le temps de retard))

  Hi spinup,

  better you should post your question in the forum of LabVIEW, LabWindows/CVI is used

  Good luck.

• Detect a noisy signal

  Hi all

  That is the most effective method to differentiate a noisy signal of normal. The application receives signals and it should be able to determine if the signal is disturbed or not pragmatic. There also a value of threshold for spikes in noise that it must consider.

  Thanks for your time in advance.

  Concerning

  IB...

  I agree that the answer depends on what your signal looks like, but it wouldn't be difficult to determine if a signal is noisy. If your signal of interest is sinusoidal, you could do a FFT, then threshold levels other than your target, as a basis for comparison of noise signal. It is quite effective. If you have something that changes a little, like audio or data, here again, you might look at the spectrum, but look outside a frequency band and not only a single frequency. If you have a reference signal, you could subtract the received signal reference signal and the result would be your noise and you could measure it. This all happens to determine the quality of the signal, using filtering will help you clean it up, but not tell you how noisy, it is first of all.

  Hope that helps.

  Chris

• Measure the time between two digital pulse

  Hello

  For a non-critical calendar application, I need to measure the time interval between consecutive TTL pulses, ranging from the order of 0.5 s for a few seconds, with a low accuracy of +/-10-50ms. The interval being measured varies between the rising edge of the first pulse and the front of the next and so on.

  I have several input lines I need to deal with. Because it's a critical machination low cost, I don't want to use digital counters for each line, so I work with an acquisition of data USB6008 and have connected the input rows TTL on the digital inputs of the device. Avoiding will be sufficient.

  I found a good example of VI on discussion forums that does almost the same thing, only it uses instead of the DAQ Assistant user input. The VI works including the time the program going on in a while loop. I replaced with the DAQ Assistant output (a channel) user input in the hope that it is still work.

  

  When I run the program in "run once" mode, it seems to work perfectly. However, in "continuous run" it measures only a very small interval, probably just the time between two samples.  I think it has something to do with the help of a while loop in combination with the DAQ Assistant. Anyone who has any suggestions how to solve this problem?

  Thank you!

  OK... first of all, you should never use the button "run continuously.  I wish that NEITHER would be to eliminate it, but told me that it is sometimes useful for debugging.  If you want your program to run over and over again, use a while loop with a stop"" button.

  If I'm reading your code correctly, you make your initial moment, and then collect data from data acquisition.  When one of the channels is "T", you stop your loop and the end time of capture.  (By the way, why you convert your table to a cluster?  Why not just index the appropriate channel in the table directly?)

  Since you want to capture the time between two consecutive pulses, you need to know when a transition has occurred... i. e when your digital line went from F (no pulse) to T (pulse start).  This will give you your forehead.  Right now, all you're doing is looking for a value T - so you have no way of knowing if you are looking for to the previous impulse again, or a new impetus.  You also burn 100% of your processor with the way you have your programme in place.

  You need a small loop delay so that your VI is not 100% of your hogs CPU time.  Given that you can live with an accuracy of 50msec, what I suggest that you use.

  See attached picture for you give an idea of how to implement.  He will probably need some refining operations, but it should point you in the right direction.

  

  I hope this helps.

• How to measure the difference in time between the passage by zero of a sine wave and the rise time of a pulse on a same graphic?

  I have a sine wave of 50 Hz and a pulse of the signal on the same chart. The difference in phase between the two is between 0-90 degrees.

  Now I need to calculate the time difference between (when the sinusoidal wave passes through zero volts) and (when the pulse increases). The frequency will remain about even for the two signals.

  The request is for a three-phase generator. In simple terms, when the difference in time between the passage to zero of the sine wave and pulse increases increases, it means that the load on the generator has increased.

  I am a novice user of LabView (version 9, 2009), maybe it's a very simple problem but I was pulling on my hair for the past few days and couldn't understand anything. Any help would be greatly appreciated. I use DAQ USB-6008 to measure these tensions and the impulse of the generator and a sensor

  I have attached a jpg file (a graphic that I just did with excel to explain). The time 't' is what I'm trying to measure

  

  See you soon

  Zdzislaw

  Awais.h,

  For problems of this kind I recommend start writing the granular steps you would take to manually fix this problem.  You can't say LabVIEW (or any programming language) If you can't succinctly describe the solution to your problem.

  The I want to address this problem is to:

  1. find all the zero crossing points and edges on the rise
  2. for every rising edge find the difference between the timestamp and previous passage by zero

  Here is an implementation of this algorithm LabVIEW:

  

• Hello! so, recently, I dropped my macbook pro! I was in public so I had no time to peak it upward and examine it! So, I just put is right back in my bag! It was a long dropp 1.6 feet! the flashing on the lower front part but the screen won

  Hello! So, recently, I dropped my macbook pro! I was in public so I had no time to peak it upward and examine it! So, I just put is right back in my bag! It was a long dropp 1.6 feet! on the lower part front light blinks but the screen lights! It also makes a really weird annoying beep I've ever heard for! Don't know what to do! Nothing reallt work screen, keyboard! but some how it turns on but shows no sign of working again! Help is needed!

  (Sorry for my bad spelling)

  Take it to a Genius Bar.  Assessed it the damage and get a repair estimate.  The evaluation is free.

  Locate your backup, you may need it.

  Good luck.

• The time between VISA W/R

  I use VISA in communication series with PIC18F4550 (mcu, USB copy series), I found if I read immdiately afte writing, I can't get the right data all the time. It seems that the time should be at the same time between write and read funciton, and delay must be greater than 0.35 sec.

  Fact delay is necessary or I used to misuse Scripture VISA and playback function?

  Also look at the use of the chariot of termination and the setting of time-out to your advantage.

  1 turn on the tank of termination (depends on YOUR DEVICE PIC18F4550, read the instructions)

  2 set the timeout to something MUCH longer than necessary. (like 1000 ms)

  Write then followed the reading. No delay, bytes read no. to the port

  For the bytes of lonely bytes expected reading feature request.

  The Read function will wait for the full message that ends with the chariot of termination and will return with your message as soon as he gets the chariot of the termination. Or will he wait until the timeout before giving up on your device.

  You can then decide what to do with if time-out error message never comes.

  I have devices that take more than 3 seconds to answer because they have to go do something before they can meet. Some of my exhalations runs to as high as 10 sec. I have set the timeout on the fly, based on the order that I send.

• Let a burn of LED on a random time between 3 and 7 seconds

  Hi all

  Probably, it's a matter of simpel for many of you, but not for me. I try to make a counter reaction time. And I hope someone can help me with the first part: the led must Flash on a random time between 3 and 7 seconds.

  After this need to measure the time between burning directed and by pressing the stop button

  Results ranking in a table

  After the display of ten measures of response time average.

  I hope someone can help me to launch it, I need it for school.

  Thank you!

  Matthijs

  Netherlands

  Code Simon put tapped off.  The Down button was a nice touch, but cannot be disabled so we were testing times preaction and the param 'Trial' could get pretty messy especially on a series of rehearsal

• Take the time between two values

  Hi people,

  I have a problem and I know idea how to solve... I need help.

  The problem is I want to take the time between two values max as you can see in the chart.

  For example, in the image that I have add

  4.5 - 1 840 = 2.66

  And enter this value in the 'time between mostra '.

  It's that I want...

  But what I think is very complicated, because I don't know how to take the time correctly and does remove...

  Thank you very much

  Any solution?

  Hi jocuma,

  I tried something and hope that helps u.

  Just create two arrays of temperature and voltage. First of all, I'll get the value of the voltage when it is more of a certain value and that same index to get the value of time and store in the shift register.

  When I get the second higher than the limit value, I'll get time and subtract the previous value.

• How can I measure the time between each two successive increase edges, using digital input?

  Hello

  I have tried two measure the time in seconds between each two successive rising edges on a digital input.

  So far I managed to detect the rising edge, increment a counter at each rising edge and take the time during which the increase is edge

  all I need now is subtract edge currently rising from the previous era of edge rising to calculate (T), which can be 1/frequency and display in real time for the user.

  but I do not know how to do this

  Can someone help me please!

  Woah!

  Sorry Apok, but your code becomes much too complicated and salty. I don't think that all records to offset or Boolean conversion/operators are necessary at all.

  If you want to measure the time between two keys so it's another (much less complicated) way. It simply records the time when press button in a registry change, then compares the two.

• the BACKSPACE key does not work properly and if I want to enter the same letter twice it takes time between them

  the BACKSPACE key does not work properly and when I want to type a leter twice I have white some time between them

  Hello

  In what program?

  Don

• Nor-Daq 6251 set hour/time between samples

  I'm trying to calculate the expected error for an experience that I do and I don't know if I've done enough to determine the 'break-in' or the time between samples.

  We use 8 differential channels to the maximum sampling frequency, the card can do (1.25. MECH / s). If I understand correctly, the minimum time between each sample must be 1 / 1.25 M, or 800 nanoseconds, such as the maximum time between sampling channel 1 and channel 16 would order 12uS (800nS * 15). If the expected voltage settings are the same for each channel (+/-10v), would a break-in? If so, how long?

  In addition, if a channel is upward, and its tensions have an offset, DC on 5 or 6 volts, should that severely increase break-in if all other channels averaged about +/-1v?

  I'm sorry for the basic question, I couldn't find a straight answer in the documentation.

  Hi LSUgrad85,

  When looking for specific device information detailed Specifications for this device will usually provide the details you are looking for.  After the back if you have questions about the information in the detailed specifications.

  I hope this helps!

  Kind regards

• How to set the time between workstations and Server 2008 R2

  Hello world

  I have problem with my Server 2008 R2

  all the workstations on my company doesn't synchronize the time on the domain controller

  I tried many ways to set up automatic synchronization via command prompt (Net time) and its does not work

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  Windows Server forums:
  http://social.technet.Microsoft.com/forums/en-us/category/WindowsServer/