I want to control the ball which is present in a 2D picture.When ever the ball hits slide control it should bounce other wise it should stop.
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How can I control the ball movement using slider?
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TCP communication with third party hardware
Hello
I am trying to get a code to communicate with a third party hardware by TCP. To start with sending strings and returning data. I have looked up some of the examples and the code should be ok. Any advise as why it is not working would be appreciated. Thanks!
Please find the VI as attached.
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1-axis PID control of a Quadcopter using myRIO LABVIEW
Hi.
I'm trying to balance a Quad-copter on a single axis using myRIO. Im using the onboard accelerometer for reading the acceleration on the x-axis, but there is a lot of noise which is due to the 4 motors. I have tried a variety of combination of PID gains but the oscillations dont go away. The copter keeps oscillating around the axis. Kindly see the attached VI for more details. What more should I do to stabilize the copter?
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dynamically called VI
Hi,
I am new to labview
I wanted to call a subvi in another VI. the subvi is for setting the parameter of spectrum in spectrum analyzer. The subvi front panel should be open during ng runtime to take input and after pressing ok it should close. Pl suggest a method.
Thanks
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Using a capacitor to reduce noise on AI signal
I have an application where we are reading 30+ AI signals which are 4-20 ma, converted to 1-5 volts using a 249 ohm resistor. This is done for channel count reasons to stay within a PXI 8 card chassis. Anyway - we have used this setup numerous times and always get noise on the signal, even at steady state. Without getting specific on sample rates, I can tell you we ready the signal very slowly, and there is not a fast rate of change on the signals. Typically I would average 15-20 samples and would get by. But recently it was recommended to use a capacitor in parallel across the terminals for smoothing of the signal. It seems fairly common, but I am struggling to determine a size of the cap. So far I have come up with a 1uf, 100V, ceramic cap. Can anyone tell me if this is ok? And I would like to buy a size up, and a size down, can anyone recommend those? like perhaps .5uf, and 2uf, etc? So I can try each one and see the effect on the signal. I would imagine a cap WAY too large would kill the response of the signal, and one too small would have little to no effect?
Thanks
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Shared variable not communicating with code
Hi all,
I am working on a project where I need to work with a code that came with a thermoelectric controller. Normally, I would just edit the code that came with the controller; however, the company I got the source code from did a horrible job of formatting the code, and it seems virtually impossible to work with due to the size (I tried the clean up function, but that only did so much). My plan was to create my own VI and make a shared variable that would interact with the source code, but I'm running into some issues. I need the shared variable to be able to take inputs (temperature values) from my own VI and output them into the source code, which I was able to do. However, I'm unable to get my shared variable to communicate with any other part of the code, I assume since it doesn't have a communications port. I need it to communicate with other functions, such as power output, otherwise I have no control over the power and I can only change the temperature. Is there a better way to go about doing this? It's possible that I'm going about this wrong, but I'm fairly new to Labview, so any help is appreciated.
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Attach and Change Images in Front panel
Hi!!
Please help me, I wanna use Images in front panel and change when is necessary, but I not find the tool to do.
Thanks for all
Best Regards
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DAQmx task created, read, closed in a for loop, time is correct on first iteration, but goes to 3.592396E+9 after
Hi guys,
First post, forgive clumsy question structure. I have a for loop, with a while loop nested in it, as shown in picture. The intent is to create as many separate files as parameters I have set, each beginning at time=0 going to end of test. This works in the first loop (in the first file saved per execution) but in the following files the time begins, and ends at 3.592396E+9. Why is this happening and how do I get this file to start from 0 on each new for loop iteration.
Also incl. is a pic of correct and incorrect file time beginning values.
Thank you very much.
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Drag and resize shortcuts
Hi friends,
I want to improve my performance, and for this, I would like some solutions for:
1 - Drag objects. This is difficult when I have to drag a control/indicator array in front panel or an array constant on a block diagram.
2 - Expand array, both in the front panel or block diagram, when a constant.
3 - Resize Indicators from arrays both in the front panel or block diagram, when a a constant.
4 - Select entire wire without double click.
I think that is very efficient for all of us, but I did not find it anywhere. Beacuse the thin border of array constant or controls, or wire case, is difficult to resize, expand or drag these. Many times, undo the array when you want to move, or exapand when you want resize, etc ................. is there a keyboard keys to block mouse pointer for just drag, or resize (that little hand .....) ???????
Thanks
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synchronized pulsegeneration
Hi All,
Please refer the VI snippet – I am using PXIe-6358 on PXIe-1082 chassis to generate two synchronised pulses. First pulse is continuous and falling edge of that is a re-triggerable start, for second pulse train which outputs 360 pulses per first pulse. Falling edge of the two signals are in synch.
My next goal is to vary the frequency at run-time. I have managed to get first pulse frequency changed but labVIEW alerts an error as the second pulse is set to finite samples on timing. This restricts me to continuously generate two pulse trains while giving the flexibility to change frequency on the fly.
I really appreciate if someone can help with some tips to overcome this barrier.
Many thanks in advance
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Why is the Timed-Loop shown as a background priority thread by the Real-Time Execution Trace Toolkit?
I have a simple example running on an NI Linux Real-Time target (NI-9651). The code is just a time-loop performing a matrix inversion every iteration.
I've used the execution trace toolkit to monitor the execution of the timed-loop. (Please see attached images)
I have 2 questions:
(1) Why is the timed loop being shown as a background priority thread (see "TimeLoop_trace.PNG"). According to the LabVIEW docs, "LabVIEW executes the timed structures at a priority level below the time-critical priority and above the high priority." And, according to the Real-Time Execution Trace Toolkit docs (see "Execution_trace_priorities.PNG") a higher priority thread should *NOT* be blue as shown in the attached trace.
(2) If the timed-loop has a higher priority above all threads except "Time Critical"... why is the LV_Occurrence (1492) being allowed to preempt the timed-loop "L477999708 (1815)"?
These questions have come up while I'm debugging a timed-loop not performing well at all in a larger application. The timed-loop is behaving as if it is a background priority. Now seeing the output of the Execution Trace Toolkit I'm seeking input from the community...
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LED step function
Hello, I'm new to VI. I'm trying to graph the blinking of an LED. For example, when the LED is on it'll have a max amplitude ( 1 for simplicity), when off, it'll go back to zero.The user is able to control the blink rate. I'm having trouble making the connection from controlling the LED to visualizing it on a graph.
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Gravar video en MP4
Moved to another board
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Measuring time delay between Arduino Uno and Labview
Hello,
I am very new to the community so please forgive me if my question is trivial.
I am a University researcher and I have been given the task to measure the time delay between labview and an Arduino Uno. The problem is that we are controlling an Arduino Uno board with labiew and want to measure the time delay that it takes for the input information via labview to be carried out on the Arudino Uno. I have an oscilloscope in my possession as well but am still not sure how I should go about testing this. If any of you have an idea of a good place to start measuring this time delay please let me know.
Regards,
Optics22
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Partial TDMS file corruption
I had a problem with a data logger, in which the CompactRIO ran out of space while it was logging using TDMS. The tdms file was still there, but I think something happened to it. When I open the TDMS file, it actually opens and reads fine in Excel, but only with the associated *.tdms_index file. Without the .tdms_index, it does not automatically generate a new one when opened. Instead, I get this error:
USI encountered an exception: TDS Exception in Initialize: Tds Error: TdsErrNotTdsFile(-2503)
USI encountered an exception: (208): Error while reading model <filename readonly='yes'>(C:\filename.tdms)</filename> (TDMS), code: 80
In addition, I can't read it using the TDMS File Viewer in labview, and I get the same -2503 error.
Is there a way to fix the file so that it can autogenerate the tdms_index file correctly? Or is the best way is to copy and paste the readable TDMS file into another xlsx file, because I would rather have it retain the TDMS type.
Best Regards,
Linus
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Intensity graph save as tiff with z value
Hello,
I have an intensity graph that I would like to save as tiff with its z value (contrast). When I save as tiff, it saves as raw intensity graph (contrast from 0-255) without contrast that I'm seeing from the graph. Is there a way to save the intensity graph with current contrast?
Thanks in advance.
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Numeric Array to String
Hi,
I have an array of U8 data that I need to convert to a single string of numbers.
The array is quite large and I can convert to a single string of numbers by looping through the array and converting each element to a numeric string & concatenating each converted element to string.
I am wondering what is the most efficient/faster way of converting?
Thanks & Regards,
Shane.
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Problems in Keithley 4200-SCS Labview Driver
I am using labview drivers for Keithley 4200-SCS, downloaded from Tektronix official website: https://www.tek.com/software/4200-scs-labview-lv-version-7-driver-beta-release-25mb
I take a test by measuring the I-V curve of a resistor on a probe station using KITE in 4200-SCS or using Labview program KI4200.vi. Parameters in two cases are all the same but the results don't agree with each other. And I find even when there is no device on the probe station, test using Labview still gives the same result as there is a resistor. So I guess there must be something wrong with the drivers.
Attached are the curves I get. Thank you in advance for your answer.
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Digital waveform transitions
Can someone please explain why my "transitions" array is empty in the attached? I would expect a transition to be the index into the array where the nibble (in this case) at that point is different than the previous value. For the attached, this should be every index, I would think. But it's not....
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Activation codes
Hi, I am currently using the Evaluated Version of LabVIEW 2017 and now its asking for Activation codes for some more development tools. So it would be great if someone could guide me with this.
Attached is the version i am currently using.
Thank you.
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