This is the second installment of cRIO-FRC training produced by National Instruments.
FIRST Robotics: WPI Library Overview
This video will walk you through the different palettes and functions that make up the LabVIEW WPI Robotics Library.
Please post feedback! We want to make our training material the best possible.
Cheers,
Mark
After you’re done watching the video, check out the library documentation, which was posted yesterday. http://decibel.ni.com/content/docs/DOC-2453
FEEDBACK:
Is this robotics programming guide for the FIRST robotics competition publicly available yet?
“The analog trigger can be used to convert an analog signal to a digital signal”. Honestly, this baffles me. Can we now deal with true analog signals on the block diagram? How is this different from the functions on the Comparison sub-pallette?
“The VIs on [the I/O] pallette are meant to be used for low-level applications, where you are using custom sensors, actuators, or motors.” Can we now use custom motors? “Use the VIs in [the PWM] pallette when you’re using custom motor controllers or servos.” Are they custom motors, custom controllers, or both?
“The driver station VIs can receive, interpret, and display both the analog and digital data from your various sensors and joysticks.” What are the datatype limitations? What is the data throughput? (typical, maximum, minimum, and what variables influence it)
“Use the joystick VIs to get information about one or more of the Joysticks you connect to the driver station.” Again, what type of data is accepted? Could I connect USB tablet or touch-screen and use that? Can data be sent back to the joysticks?
“You can use the camera VIs to acquire images with the AXIS camera.” Is there a ‘cache’ to store previous pictures? Do the VIs acquire images at up to (and no greater than) 30 times a second? Does it store the images with a timestamp?
Thanks!
Yes. NI hopes to make this available once it is completely up to date with the LabVIEW FRC package software.
-Mark
Okay, I looked through a lot of the help files, and they answer most of my questions, but I’m still not quite sure how access images from the camera.
Does this mean the image is saved to a destination and we access it through a filepath?
This description would hopefully make more sense when looking at an example. But what it is really saying is that there are two images inputs, one names src and one dst. Src is required, and dst is optional. The function will output a new image and store it in dst if it is wired, otherwise it will store it in src. So if you don’t want src to be modified, be sure to wire up dst. Otherwise, this will work anyway by reusing src.
This has nothing to do with file paths, the images it is referring to are NI IMAQ image references which are memory based buffers.
Greg McKaskle