acquiring data from an ecoder and Ultrasonic sensor

[mechanical Engineer]

I have a controller card PCI-7340 and UMI-7774, connected to my PC, I want to implement an autonomous vehicle through mounting a quadrature encoder for velocity and position feedback and an ultrasonic sensor for obstacle determination and avoidance, and I am implementing now a fuzzy controller to make a control system capable for moving the vehicle, but my problem that i don't know how to acquire the data from the encoder or the U/S sensor in order to enter it to the Labview code, knowing that I am using a PWM circuit for speed control and amplification of analogue voltage out from the UMI-7774, if u have an example or u can give me a guide to how implement this on Labview.

[BullDozier]

Hey NMWLV,

Thanks for contacting NI.  I've been looking over your system and I would connect the drive up to the UMI, also connect up the encoder to the UMI, and depending on how your range finder interfaces, possibly hook it up to the UMI as well.  If your range finder outputs a digital signal, then it is possible to use the Digital I/O on the motion card to possibly interface the card.

As far as an example goes.  There are several good examples on PWM as well as encoder feedback.  There may not be an example for generating a PWM and reading encoder feedback, but there are definately examples for both of those.  One example that shows how to use the feedback through NI-Motion is "One-Axis Move with Position Monitor.vi".  It can be found in the example finder under Hardware I/O >> Motion Control.  A good example for PWM is "PWM Output.vi".  I hope these examples help you out.  

As for figuring out how to interface your range finder, I would imagine, if it is communicates over parallel digital lines (multiple lines at the same time) it would be rather easy to communicate with it by using the digital i/o ports that are on the motion board. If the range finder communicates over serial digital lines (one line of bidirectional communication), then it will be a little more complicated to talk to your range finder.  Good luck with your application!  I hope it turns out ok.

Take Care,