Motion control and feedback is inverted

I have an application where the motion control and feedback is opposite of what should be commanded.  I am using LabVIEW 8.2, a PCI-7344 motion card, Pacific Scientific PC833 drive & a servo motor w/resolver.  The PC833 is emulating encoder feedback to the motion card.  I've tried swapping control/feedback signals and the system becomes unstable.  Is there any settings in max/LabVIEW to inverse the control/feedback, or are there any suggestions on what to change in the wiring to get the system to operate properly?

I am going to assume that you mean that when you command a positive move, the motor goes negative, and runs away quickly.  Different drives handle changing direction differently, but to get basic control, just switch one pair of the feedback signals going to the controller.  Swap A+ and A- or B+ and B-.

Similar Messages

  • RTSI motion control and data acquistion

    The code attached is part of an example that uses every falling edge of an encoder pulse via a 7334 motion controller card to clock data on a PCI6023E card. (Position-based DAQ)
    Is there a way using this code (or otherwise) so that I could use this signal or some other signal to only TRIGGER the daq on the 6023E? (I want time-based daq)
    Thanks for your time and patience
    Chris
    Attachments:
    example.vi ‏99 KB

    You can definitely use a pulse to trigger an analog acquisition on the 6023E device. I would suggest to look at a LabVIEW shipping example that illustrates how to integrate a digital start trigger for analog aquisition.
    The 'Acquire N Scans Digital Trig VI' would be a great place to start. You will just need to add a control/constant to the analog chan & level input of the AI Start VI and enter "RTSI0" into the string of that cluster input. This will set the 6023E to trigger off of RTSI0. So, instead of using the RTSI line in your program for the analog scan clock, you will use the RTSI line as a digital start trigger.
    I hope this helps.
    Regards,
    Todd D.
    NI Applications Engineer

  • Simple stepper motion control

    Hello all, I am completely new to motion control and my head is spinning with all the options so please bear with me, all help is much appreciated.
    I am trying to build a control which will perform point to point movement of something like this:
    http://www.haydonkerk.com/LinearActuatorProducts/StepperMotorLinearActuators/LinearActuatorsHybrid/S...
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    Hi Nick,
    We've got two basic options for motion control- PC based, or RIO based.  These types of questions are actually quite common for support, if you'd like to contact NI. If not, post back and I'd be happy to help. 
    Cheers, 
    Marti C
    Applications Engineer
    National Instruments
    NI Medical

  • Is it possible to generate a motion control vi from parameters entered into MAX?

    In the process of familiarizing myself with LV, It was brought to my attention that it might be possible to generate a VI from parameters entered into MAX. Is this possible?
    Right now, I am getting familiar with motion control and LV by using MAX's 1D and 2D motion controller interactive environment. I was wondering if there was a way for LV to take the parameters and selections I have made in the various fields and make a VI from it?
    I have tried searching MAX's help, Google searching, etc. but have not found anything.......
    Thanks

    In LabVIEW you can use "Initialize Controller.flx" to load the configuration settings from MAX to the motion control board. There is no way to create vis from the Interactive window, but if you are looking for such a feature, you may want to look into the NI Motion Assistant.
    NI Motion Assistant is an interactive environment for prototyping your motion control application without programming. Later you can export your motion sequence to LabVIEW.
    If you want to test Motion Assistant, you can download an evaluation version here.
    Kind regards,
    Jochen Klier
    National Instruments
    Message Edited by Jochen on 02-12-2010 02:48 PM

  • Is it possible to condition a load cell signal with a 1520 SCXI and then use it as the primary analog feedback for a 735X motion control board?

    My system
    PXI 1052 chassis
    PXI 8196 RT controller
    Flexmotion 7356 motion controller
    Flexmotion 7354 motion controller
    6259 M series DAQ
    1520 SCXI
    1520 SCXI
    1314 SCXI frount mounting terminal block
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    Exlar SR Brushless PM motors
    Kollmorgen servo star CD series 5 drives
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    I want to measure the force on the load cells with the 1520 SCXI (i.e. excite the load cell then amplify and condition its output) then I want to use this analog (force) signal as the primary feedback for my motion control system (7356 and 7354 motion controller connected to my drives and motors).
    The problem:
    The motion controller boards (7356 and 7354) can be configured for force feedback control via analog feedback from a load cell.  However the boards implicitly expect the load cell signal to be amplified and conditioned with and external signal conditioner rather then using an NI SCXI module.  Currently I’m am reading the SCXI signals via the 6259 M seriers DAQ and consequentially have no way to route the signal into the 735X boards for force feedback control.  I can use softmotion to control the motors but then I loose the fast PID update rates possible with the 735X boards.
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    Is it possible to condition a load cell signal with a 1520 SCXI and then use it as the primary analog feedback for a 735X motion control board? 
    Thanks
    Patrick Aubin
    Ph.D Candidate
    University of Washington &
    VA MedicalCenter of Excellence for
    Limb Loss Prevention and Prosthetic Engineering  

    Hi GG,
    Thank you for your feedback.
    >create your own external circuitry to amplify the signal.>
    True a few op-amps could amplify and filter the signal externally but the performance of such an amateur built system will never match the accuracy and functionality of the 1520 SCXI.  That’s why we spent the $2500 for the professional version.
    >One thing that you could do is to use a UMI with your motion controller and then wire your signal from your SCXI to the UMI.>
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    Again thanks for your input GG.
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  • Simple straight line motion control with brushless motor and encoder/mi​croswitch

    I want to go build a motion control system/program using labview. I have a brushless motor and a controller and a National instrument DAC (NI USB-6009). This is how my system looks like: receive an input signal 4-20mA, this should be converted to 0-5V for the controller for speed, controller should move motor till it hits micro switch. The micro switch/encoder should generate a signal (5V) back to shut the controller. I want to record the position of the motor in labview. How do I do this? How do I set the system up? Thank you in advance

    Controller from anaheimautomation: MDC151-050301
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    Controller and motor go together.
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    My end result should be whwn I turn on the system or start the program It should detect whether it is at the home position, if not travel to home then respond accordigly given an input signal(4-20mA).
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  • Motion control: PXI 7350 controller and UMI 7774 to interface with third-party driver UDK5114NW2

    Dear community,
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    Hau Nguyen.

    Dear Community,
    I said wrong, 4 disable LEDS on UMI 7774 Board instead of 5 as my previous post. Why nobody help me to solve this problem. I can not turn off disable LEDs on UMI 7774 Board so I can not start the strp motor. Please help me!
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  • Photos in Timeline and Ken Burns Effect (Motion Control)

    I'd like to check my processes for setting photos with the Ken Burns Effect. I've used Tom's Motion Control example to set Ken Burns Effect on two or more photos that are next to each other in the timeline. I have found that if the photos are approximately the same pixel size that it works well. When they are significantly different I still see the second pic holding still for a few frames and then the movement.
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    Hi David,
    I think the problem you are having is similar to one that I was encountering while finishing a project a few weeks ago. I also was using photos of differing sizes, but the issue with the late start on the "Ken Burns Effect" on the second photo wasn't related to the differing photo sizes, but to the transition I used between the images.
    I found that when I applied Motion to a photo using keyframes, the motion looked fine on both images until I applied a cross dissolve in between images. I realized that the cross dissolve is looking for frames before the motion keyframe to blend with the previous photo. Since the frames before the keyframe are "generated" (I'm not sure if that's the correct word) from the first frame of the still (which has no motion) it generates 15 frames (for a 1 second cross dissolve) that are not moving. That makes it appear like it's stuck and then starts moving when the playhead hits the motion keyframe.
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    It was incredibly tedious, but I had to do it because the images made up a large part of the video project I was working on. If anyone can suggest a better way of doing it, I would greatly appreciate it.
    Despite the time involved, I was really happy with the final results.
    I hope that helps.
    I don't log in here very often, so if you have any questions, feel free to email me at cgonzalezat*sfchronicle*dotcom
    Good luck.

  • Problem with data acquisition and motion control

    I have PCI-6024E and PCI-7342 cards on a single PC. Servo motion control works fine when it goes alone or is accompanied by one point data acquisition in a while loop, but when I start data acquisition with specified sample rate, the motor moves with breaks.
    Does anybody know what is the problem? Is it possible to fix it?

    How are you performing your motion? Is it a position move or a velocity move? How are your triggering the data acquisition? Using breakpoints on the 7342? If so, are you using single breakpoints or modulo? How are you configuring the data acquisition rate? Are you triggering just the start to the acquisition and the unsing the daq scan clock or are you using the motion controller to send the scan clock itself?

  • Keyframes and motion control

    I would appreciate sources of information that would explain Motion Effect/Keyframes to a nonprofessional.  I have read three books and can't get an understanding.  For an example:  If i change the motion controls position from 360 725 to 360 240, what am I doing?  I would appreciate any help or reference material.  Arnie

    First, here is a TUTORIAL on basic Keyframing. It was written for an earlier version of Premiere, not Elements, but covers the basic theory.
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    Hope that this helps.
    Hunt
    PS - welcome to the forum.

  • Using PXI 7352 Motion card and 6025E DAQ

    Dear Sir,
    I am using SCXI 1520 along with PXI 1011 & E Series DAQ (6025E) to measure the Load Value of a load cell. I am also using PXI 7352 Motion card to control the velocity of a Plunger. Now my requirement is to stop the movement of the Plunger depending on the value I read from the load cell. I am not able to achieve the stoping accuracy for high speeds (around 150mm/sec) in the software. Can it be possible with the use of Motion Control card and RTSI signals? If so, how can I do that? (I am not used any limit switches as the load value at which the Plunger should stop is user programmable and I am using DAQ card in Multiplexed mode because i am reading more number of analog inputs with only one DAQ card)
    Ramkumar. D
    Soliton Automation,
    India.

    Hello.
    Based on your post I am guessing that you are performing the control in software, i.e. starting a velocity move, and then reading the load cell until it reaches a threshold, then stopping the motion. As such you are essentially limited by the software control loop rates.
    You are using PXI so it is possible that you are using real-time. If not, one solution could be to implement a real-time application that would be more deterministic, but again this would still depend on the software.
    Depending on your system (stepper or servo), you could implement a direct analog feedback into the motion card itself, but this would require a signal which has a range much greater than your load cells. This is only a good option for servo axes. If this was somehow possible, you can tell the motion controller to move to a specified LOAD instead of a specified position/velocity. Provided you could appropriately condition the signal, this is the best choice.
    Unfortunately, you cannot implement limit switches/etc over RTSI, so I believe that this will not be a good option.
    A third, and probably most un-desireable option, is to output a voltage on the PXI-6025E proportional to the load received from the load cell. This voltage could then be used as the analog feedback for your motion device. This, however, still adds the software layer of delays.
    I hope these ideas help you out.
    Regards,
    Colin C.
    Applications Engineering
    Colin Christofferson
    Community Web Marketing
    Blog

  • "Distributed motion control'

    Hi there,
    For a future project we are making a first study, and as I'm not really familiar with NI solutions, I hope some of you can share some thoughts.
    For this project, we will have to control the following hardware:
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     - 2 cryogenic stepper motors in open loop, but with a constantly changing position setpoint (>50Hz should be fine)
     - 50-100 I/O temperature and pressure readings (sampling in de range of a few Hz maximum)
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     - a PXI chassis in the computer room
     - an EtherCAT connection from the PXI chassis to a daisy chain of 4 NI-9144 expansion chassis, all equipped with the 28+2 NI 9512 stepper controllers, connected to 28+2 stepper drivers
     - an extra NI-9144 (or compactFieldpoint chassis) for the DAQ
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    Another solution would be to have 28+2 standalone third-party stepper "controller and drivers" inside the instrument, connected with an ethernet fieldbus to a labview target in the computer room. But I'm having troubles of finding suitable stepper controllers+drivers (maybe because stepper motors and ethernet motion control are not so commonly found in industry?)
    Thanks for any thoughts on this,
     Wim 

    We've roughly worked out a layout of such a control system on paper, but it remains a quite vague "study" until the project enters the next stage (which depends on funding since it's a scientific instrument). I can send you a document about it if you want (just PM me your e-mail address), but I doubt it'll be of much use. Anyway the final solution will look much different from our original plan, and if I'd have any say in it, I'd most likely choose a PLC-based solution over this one.
    Wim

  • 64 bit motion control ready now?

    I recently upgraded LabVIEW to 2010 64bit. Then it turned out the previous motion control VIs don't function in 2010 64bit version. The error points to the failure to load "FlexMotion32.dll". It makes sense, apparently that DLL file is 32-bit. 
    I did a search on ni.com about FlexMotion. This page http://zone.ni.com/devzone/cda/tut/p/id/3753 illustrates that "FlexMotion32.dll" is required for the communication between LabVIEW and motion controller board. Tried to find if "FlexMotion64.dll" is available, but it doesn't seem it exist yet. 
    So my question is how I can update the motion control to 64 bit. 
    Solved!
    Go to Solution.

    Hi Ian
    We value your feedback on our NI-Motion Software. We have a limited amount of resources but will take your recommendations into account for the driver. I am sorry that we do not have a 64 bit driver for NI Motion and hope that this does not slow down the development of your latest project. Please let us know anytime you have feedback we are always trying to take into account what our customers need and manage our time according to it.
    Thank You
    Eric Reid
    National Instruments
    Motion R&D

  • PCMCIA card for motion control

    Hi,
        I am trying to control a stepper motor through LABVIEW. After perusing through the site, I know that I would need a stepper motor, a corresponding motion controller and a universal motion interface. The problem I have is that I am trying to control the stepper motor through a laptop (which does not have the Parallel Port slot). I am wondering if a PCMCIA card could work (by providing a parallel port to the laptop) or if it would not meet the necessary requirements to operate the motion control through the universal motion interface. 
    Thanks

    It IS possible to drive an UMI interface with a parallel port providing TTL compatible outputs, basically the UMI interfaces are (advanced) break-out boxes feeding the step and direction pulses to a motor driver and connecting feedback signals (encoders, limit switches etc) back to the PC. But in this case, you would have to write your own routines for accelerating and slowing down, as well as evaluating the feedback signals from an encoder or limit switches. There are several manufactures making motor drivers which can be driven via a serial or USB interface, in case you cannot use a NI controller board it will be much easier to use such a setup since the motor drivers usually incorporate at least a basic motor controller providing a set of commands which makes it much easier to control a motor than with doing everything from scratch. 

  • How can I use flex motion control VI without hardware?

    I would like to try and simulate the motion control of my system before i hook up the motion control card. But when I use the VI in flex motion contro took kit it asks for address or something and gives me an error. Can't I just simulate without hardware?

    Hello,
    The only way you can use FlexMotion without any hardware is to set it up as Open Loop Stepper Control. Otherwise, you will get errors when no encoder signal is fed back to the controller.
    Please let me know if you have any further questions.
    Regards,
    Andy Bell
    Application Engineer
    National Instruments

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