how do i use my NI 6216 daq to find a angular position of an incremental encoder

[Prabhakar7117]

i have a ni 6216 daq baord and an incremental encoder (i dont know the pulses per revolution of encoder). How do i write a labview code to get the angular positon of a motor wihch is interfaced with the encoder. How can i know the pulses per revolution of the incremental encoder.

Thanks.

[Thomas-B]

Hi, 

My name is Thomas and I am an application engineer at National Instruments.

I looked through some of the information we have on file for incremental encoders and found a couple of documents that may be of help to you. 

Follow this link for some general documentation on setting up an incremental encoder to measure the angular position of your motor.

Follow this link for some example code off of which to build your application.

As you alluded to, we are going to need to know at how many pulses per revolution your encoder runs. Which encoder are you using? With a bit of research we can hopefully learn the specifications for your specific encoder. 

[Prabhakar7117]

Hi,

Thanks for the information Thomas. It really helped me a lot. But actually i dont know what encoder i am using, i couldn't find any name or model on it. Some how i found that it uses 20 slot disk inside it. I did make a labview code to find the position, and i am getting the incremental data from the encoder. But i am not able to convert that data into angular position. Can you help me? 

Thanks

JS Prabhakar,

Graduate Student,

Northern Illinois University.

[Thomas-B]

Hi JS,

Without knowing the encoder specifications, it may be difficult to find the angular position of the motor, but we'll see what we can do. 

Would you be able to post a VIsnippet of your code, or your actual VI, so I can see what all you have been able to read out thus far? 

We may be able to determine the pulses per revolution specification of your encoder through causing it to run a known number of revolutions, and reading out the number of pulses through LabVIEW. How is your encoder currently interfacing your other hardware and LabVIEW? 

Whenever I can get a look at what your are doing, we'll see where we can go from there.

[Prabhakar7117]

Hi Thomas,

 I have attached the labview file i am using right now. Here i have been using NI6216 USB DAQ Board. I have interfaced it with a robotic arm ( Scorbot ER-4U).  I have connected motors wires and the encoder wires to the daq board and i am controlling the robot using DAQ. I have used counter 1 for the PWM required for the robot motors and Counter 2 for the encoder of the base motor. Please let me know if you need more information.

Thanks

JS Prabhakar

Graduate Student

Northern Illinois University