DC motor control via ctr1/ctr0 pwm output stops outputting after one loop through.

Working on this project to control an H-bridge controlled
motor using pwm output from ctr0/ctr1 for ccw and cw on the motor. A sensor detects where it is at and each cycle goes from black to white. For some reason, the motor only turns on once and then nothing comes out of the ctr outputs after that. Anytime the program is stopped and restarted it works for one cycle. Or if just the program is run at the skipcolor sub-vi. this can be run multiple time to control it properly. During the actual run it doesn't work. Any implementation device would be great. I am using the PCI-MIO-16E controller.
Programs attached for reference.
Attachments:
SkipColor1.vi ‏111 KB
MotorControl2.vi ‏99 KB
PROJECT 2a2.vi ‏18 KB

Hey suspencefull,
You are probably going to have to think about re-designing your code. Your pulse train is not continually generating because you do not have it in a loop. When you use the DAQ Assistant to create a continuous pulse train, LabVIEW will prompt you if you want it to automatically add the loop. You must have deleted it or chosen not to add the loop.
There will, however, be problems though when you add the loop back in. The SkipColor sub VI will not finishing executing until the loop is finished and therefore you will never move out of the first frame of your sequence. I would suggest redesigning your code so that these thing can occur in parallel.
Please let me know if you have further questions.
Regards,
Chris Delvizis
National Instruments

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Steppper motor control via RS232

hii
i am new to this stepper motor controlss section.
i am using vaccum compatible stepper motor .. the whole manual of this is ayyached alongwith..and the program made by
me is also attached along with..i had run the other stepper motor with the same code..i do not know where is the problem..
please help me..
thanks
do not hesitate to give kudos

Hey Sahil,
Thanks for posting on the forums. Hopefully this was the thread you were referring to in the Engineer Awesome ni.com/community group discussion. Sorry that you did not receive any feedback from your issue, that is fairly rare.
Anyway, in regards to the issue at hand. The fact that you are using a stepper motor is not as significant as the fact that you are communicating to your instrument (in this case I would image that it is your motor controller/drive) via RS232. I hate to point you to another resource, but the instrument control forum may be the most appropriate location for your query.
In the Engineer Awesome discussion, you mentioned that you were able to control the device through a third party application but you were having trouble doing so in LabVIEW. My first reaction after looking at your code is termination characters. Does your controller expect any sort of termination character? Also, are you sure that you are sending the same commands via LabVIEW as you are in the third party application? If you use a port sniffer application to monitor the traffic over your RS 232 connection when your third party application is running and compare that to when your LabVIEW code is running (you could use NI SPY for this when you are using NI VISA), how do the two situations compare.
If I had to guess, I would think that you are not sending commands/termination characters to your instrument that it is expecting.
Lastly, a more detailed description of what your issue is, what you have tried, and what is and isn't working would really help everyone understand what is going on and how to help. As it is, it is unclear what the issue is or what you are trying to accomplish.
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2 motor control via joystick in an underwater ROV

I have a term project.I am doing an underwater ROV with labjack U3 using Labview.I do not know how to control 2 motors with one joystick.It is too complicated.I need help.??

I'm wondering a bit how you would use a USB data acquisition device for motion control, but as long as long as you don't use this for closed loop control it could be ok.
But anyway. Here are some links to example that might help you. As you could imagine NI doesn't provide examples for labjack products, but you should be able to adapt the examples to your hardware:
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Loop through all controls in view

Hi Everyone,
I need to cycle through all the controls on a view.
I have set each of the controls of type UISegmentedControl with a unique tag number.
I am using this tag number to perform a lookup in database for the value of the segmented control.
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alt-088 wrote:
I think we are close - just one correction.
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I'm not clear on what's been corrected. The sample code I gave you assumed all the controls were known at compile time. So I think the example code addressed the problem you're trying to solve. The last paragraph of that post was just an afterthought, to explain what to do in case you ever needed to add controls dynamically.
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Set segment value to value returned from database
Once again, if I correctly understand the above, the code I gave you does exactly what you want. You haven't indicated you want to take any action when a control is not a segmented control, so I don't see why you'd want to include them in the loop. However, if you actually do need to enumerate non-segmented controls (or other subviews), my last response advised you to set the tag properties of all those other controls, making sure the range of those tags is different from the range of the seg control tags.
The part that eludes me is the looping through all the controls on the view
I guess the part that eludes me is why you're so interested in enumerating all the controls, when you only seem to be interested in the segmented controls. But even if you really do need to look at every control, I don't see why you're rejecting the solution I gave you. [viewWithTag:|http://developer.apple.com/iphone/library/documentation/UIKit/Ref erence/UIViewClass/UIView/UIView.html#//appleref/doc/uid/TP40006816-CH3-SW26] is a powerful method which recursively walks the entire view hierarchy to find whatever tag it's looking for. If you use it correctly (e.g. by assigning unique tag numbers that tell you what type of control you've found), it will save you lots of trouble.
If, for some reason, you insist on doing this job without using viewWithTag, the next best might be something like this:
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Motor control using pwm,pid

Hi all,
Can anyone help with this please.
I have a counting circuit from a hall effect sensor and am controlling a motor using a PWM.I am controlling the speed of the motor varying the duty cycle and the motor is wired via solid state relay.these run fine.
What i am trying to do now is connect through a pid as to control the speed of the motor.
My understaning is that the set point is from the duty cycle, the process variable is the feed back from the sensor (rev per min) and the output is back to the motor to increase or decrease speed.
Is this the correct understanding? and if so can you help with setting up.
Attached is my vi.
Regards Anthony
Attachments:
rev per min 5.vi ‏117 KB

Continued from here: http://forums.ni.com/t5/LabVIEW/Error-200290-when-running-a-pulse-count-and-pwm-program-together/m-p...
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Message Edited by gastro54 on 04-14-2009 06:07 PM

here is the VI
Attachments:
motor control.jpg ‏148 KB

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Hi,
I have a cRIO-9014 with a NI9505 DC brushed servo drive module, and I would like to program the FPGA for PWM and Quadrature encoder interfacing using the intellectual property IP functions mentioned in the "CompactRIO Motor Control Basics Tutorial":
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More myRIO PWM outputs via FPGA

I'm working on a project with the myRIO that requires 9 servo PWM signals. I know that the PWM Express VI operates on 8 different pins among the 3 connector ports on the myRIO. After spending a few hours researching FPGA, I was getting no where since a lot of it is beyond my skill level/understanding.
So my question is: what is the simplest way to create more PWM signals with controllable duty cycles on the myRIO FPGA? I wanted to have all the servos attached to pins on one connector for simplicity (e.g., all on MXP-A).
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Sorry for the delay Sam. I figured out how to add the PWM outputs via FPGA and it works. Then I tried to accomplish this while still retaining the functions of the other connectors. My method was to go into the FPGA personality and replace all of DIO-A's FPGA with my PWM code while keeping all of the FPGA code for the other connectors intact. The files are attached.
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Attachments:
myRIO-1900 Customized FPGA.vi ‏388 KB
RT Main.vi ‏506 KB

I'm working on DC Motor control using DAQ. There is sufficient voltage output from DAQ but not current. What should i do so as to drive the motor

I'm working on DC Motor control using DAQ. There is sufficient voltage output from DAQ but not current. What should i do so as to drive the motor. Could you suggest me appropriate driver IC using which this problem can be solved.
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You really should use a DC motor controller to control a DC motor, look at the 754410 IC for a good example. You should be able to interface these to most DAQ devices.
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A/C three Phase motor control using 1/4 bridge Load Cell output and a USB 9172 Daq

NI Assistant,
I am tasked with setting up a Motion Control using two each OMEGA LC712-100K, -50K and -10K load cells to monitor the cable tension on six A/C motor driven winches. I also need to Monitor and calculate a Moment as well as the load slope for Load verses Time.
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I setup a drawing in Word to visually define the task.
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Attachments:
Layout for Testing Spars.docx ‏15 KB

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The reason why the Motion Control examples will not work for you is beacuse they are meant to be used with the NI Motion boards. Since you are using DAQ boards, the examples are probably not going to be able to help you too much. However, there is one example on the community that might be a place for you to start.
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Hello,
I am using maxon motor control PWM servoamplifier ADS 50/10 for my application.I am currently working on a project that requires me to get the precise position (mesure) with an incremental encoder with 2 channels A and B. I am Using NI Motion, NI UMI-7774,NI PCI 7550, and Labview 10
I try to connect my maxon direct with the Labview Hardware NI UMI 7774 and i don t know how to do this.
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Hello,
can you please give me some more informations about the problems you see with the connection?
Generally you have to at least connect the "Analog Output", the "Ground" and the "Enable" from the NI-7350 with the Maxon ADS 50/10.
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http://www.ni.com/pdf/manuals/373359c.pdf
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Hello,
I have a PXI-7354 Motion Controller in a PXI-1033 rack and I'm trying to prototype a product which has a digital motor controller IC, A3906 by Allegro. The IC is controlled with PWM signals by varying the duty cycle. Now, in the NI 7350 User Manual on page 5-17, it says that "These signals (PWM) are configured in software and are in no way associated with the PID servo control loop." My question is, can I programmatically associate the output of the control loop with a PWM output duty cycle?
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I am trying to setup a simple DC motor control system with cRIO-9081, NI 9401 and AMC PWM servo drive 12A8. Can someone please tell me if this AMC drive is compatible with my other NI products? Do I need anything else to setup a simple closed loop speed control for a small DC motor? Any advice or example is very much appreciated.
Thanks

Hi SunnyX,
It seems like your servo drive is expecting an input of +/-10V analog. Are you able to confirm this in the device manual? If that is correct, you will not be able to generate the necessary signal with the 9401. You will need another module that you can program to output this signal such as the 9263.
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DC motor control via ctr1/ctr0 pwm output stops outputting after one loop through.

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