Real-Time Measurement and Control

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crank angle measurement using quadrature encoder

I'm currently using compactrio and a NI-9401 module to read signals from my quadrature encoder. While i was able to find example to help with the velocity measurements, i'm yet to find one that would help me reset the position to zero after every 360 revolution. I know the Z signal should be used for that and i've tried some other examples (including one in the labview example finder) but none of them works. I have to manually click a reset button to get the encoder position to zero. Please, is there anyone who knows how to do this? I also know the new scan mode in labview 8.6 does this pretty easily but the scan mode limits sampling rate (scan period) to 1ms using the scan engine but i need at least 8.33 us because of the high rpm of the engine and high resolution of the encoder (1440 pulse/s). Hence,my decision to use fpga mode. Please any assistance will be highly appreciated. Thanks.
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I'm not sure on how your decoding your quadrature encoder but I convert the X and Y channels to up down one shots.  If this is what your doing, then something like this would give you position.  I call Z signal M for marker.

TT Decode.png

TT count.png

 

 

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hello

Can i have the project file for this particular example that you people are talking about? I need to run the same thing but I am not finding it anywhere

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