The Secret Book of FRC LabVIEW
 

When I first started trying to teach LabVIEW programming to FRC team members, I became very frustrated. I don't program for a living, but I do pretend to be a semi-competent LabVIEW programmer at work. But when I started with FRC, I found the Robot Framework completely mystifying. Worse, I could not find a book to explain it all to me.

Here is that book. Or rather, a first draft. Please respond with typos, errors, glaringly obvious topics I should have covered, but didn't, etc.

The book is a PDF, but zipped to squeeze under the 5 MB size limit.

The smaller zip file contains images for use with Chapter 7.

Enjoy!

-GN

Re: The Secret Book of FRC LabVIEW
 

I gave it a quick scan and two thumbs up. You cover a lot of material without bogging down, and you keep a sense of humor while on the journey. Good one.

Maybe you've re-inspired me to spend more time on my writing project.

Greg McKaskle

Re: The Secret Book of FRC LabVIEW
 

I'm only half way through, and enjoying the read. It's nice to see someone else's approach to teaching LabVIEW. I'll be recommending this to our programming team as an additional viewpoint. Thank you for taking the time to put this in writing and share it with our community.

Edit: Finished it. Loved it.

Re: The Secret Book of FRC LabVIEW
 

I've been pretty busy lately, but hopefully when I get the time I will be able to read it and give you an opinion from someone who just learned LabVIEW in the last month.

This should be a great resource. I think that something like this was really needed.

Re: The Secret Book of FRC LabVIEW
 

I'm so glad that this arrived before the 2014 season so other rookie teams and new programmers have something to reference!

Great Job!

Re: The Secret Book of FRC LabVIEW
 

It's awesome!
I'll definitely use it to teach our new programming crew member's.

Re: The Secret Book of FRC LabVIEW
 

Here is a revised version that fixes a page numbering problem. I found a better PDF tool that fixes some formatting problems, and as a bonus, makes a file small enough to upload without zipping.

Happy Diagramming!

-GN

Its written there that new packets are sent to the robot every 100ms, isn't it 20ms rather than 100ms?

Re: The Secret Book of FRC LabVIEW
 

You are right. I don't know where I picked up the 100 ms number. (The difficulty in finding out this kind of stuff is part of the motivation for the book.)

I'll post a corrected version in a week or so. Let's see what other wrong things can be found!!

Cheers,
-GN

Re: The Secret Book of FRC LabVIEW
 

On Page 14, you mention the clean up tools that are less than helpful in Labview. As a note, the Ctrl-U block diagram cleanup was made incredibly useful a couple years ago when they limited the clean up process to only the items on the block diagram that are selected.

So, you select a group of items, press ctrl-u, and it cleans up only the highlighted code. Bam!

Re: The Secret Book of FRC LabVIEW
 

I got really confused from the PID chapter.
the math is too complex to understand right away,
maybe it'll be better to explain the idea of PID and how it works in general and some examples of it explained it detail, and only then to tell about the math behind it.

BTW can u upload the labview file of the PID simulator? (for both victor 884 and jaguar)

Re: The Secret Book of FRC LabVIEW
 

This is great. i really appreciate you putting this together

Re: The Secret Book of FRC LabVIEW
 

Greetings all-
Attached is a new edition of the book. It addresses some issues raised by readers, as noted below. (And thanks for the feedback! It is much appreciated.)

This error has been fixed, and the discussion of timing in Robot Main improved (I hope).

I never said they were less than helpful, only that the results were not to my taste. But I like the clean-up only the selection tip, and have added it.

PID control is very mathematical. There's no getting around it. But I did rather jump right into it, so I've added an introductory section that explains the basic idea. It is very difficult to explain, for example, integral control with just words, however. I'm afraid that younger students with limited math won't really be able to follow this chapter. But that will give you something to work towards for the following year!

As a matter of teaching philosophy, I don't want to upload the VIs. The only way to get good and fast at coding LabVIEW is to have lots of practice coding LabVIEW. Hence, no uploaded VIs...

Re: The Secret Book of FRC LabVIEW
 

Proportional: "The greater the difference between the set point and the feedback signal, the stronger the output signal."

Integral: "As long as the feedback signal remains different from the set point, the integral control portion of the system keeps increasing the output signal."

Derivative: "While the feedback signal changes, the output signal is decreased based on how quickly the change is occurring."

Re: The Secret Book of FRC LabVIEW
 

I agree. Most high school students who are learning labview don't know what dy/dx means, so I don't see why one would start a chapter with it. Maybe have a chapter explaining the math, and another with code? I don't know, just a suggestion. Really threw me off once I got to that chapter. It was all step by step based, then bam here's an equation and here is how it is used. I don't have a solution, but it needs to be addressed.

Other than that, the book is perfect. It made me laugh out loud reading it at times while in class today on my laptop. I got strange looks, but hey, I was learning. (Isn't that what is important?) Thank you for putting in so much time and effort. I consider this a holy grail for FRC. Great job. Makes me want to do one on computer vision, but there are just so many ways to do it.....

Re: The Secret Book of FRC LabVIEW
 

In page 127 it says:
You've already changed the 100ms to 20ms, so this sentence is wrong.
You actually need 50fps to be at the same rate as the communication :)

Re: The Secret Book of FRC LabVIEW
 

Thank you for putting together this manual, it is a great resource.

I have a question regarding your discussion on file organization, page 50, do you have any examples for this:

Thanks

Re: The Secret Book of FRC LabVIEW
 

Thanks for noticing. This kind of catch is very helpful. A revised version is attached.

I wrote utilities for zipping and unzipping the project to a flash drive (for backup and moving the code between computers). It is 10X easier to write this routine if the file structure is flat.

Re: The Secret Book of FRC LabVIEW
 

Excellent work!
I am starting through the Ver. 0.4 now. If I come across any errors, or have any suggestions, I'll post them right away.

Re: The Secret Book of FRC LabVIEW
 

Thanks so much for the book. You saved me!

Re: The Secret Book of FRC LabVIEW
 

Here it is! What you have all been waiting for!! (Or not.) The latest revision to the Secret Book, covering the 2014 Framework, reentrant VIs, and how to actually use a PID in your robot.

As always, I welcome corrections, but also suggestions for new topics, or places where I have not explained things as clearly as I should have...

Cheers to all!
-GN

Re: The Secret Book of FRC LabVIEW
 

Thanks for this AWESOME resource!

If you're still taking small edits, there's a small typo on page 123 (of book, not PDF).

In the "Loop 2" paragraph, last sentence: "We’ll discuss the stuff you can see first, and then spend some time on the
Dashboard JMPG VI, because in 2014 this has become a pretty sophisticated routine."

Isn't that supposed to be MJPG?

Love this book and I'm making all of my programmers read through it.

Thanks again!

Re: The Secret Book of FRC LabVIEW
 

Holy Moose stuffing Batman!:D
I can really use this for our students. Nice work. Hope you can find the time and motivation to keep it up to date.

Re: The Secret Book of FRC LabVIEW
 

Can't wait to start reading. On a side note, that's a very nice random image you have there. I like it.

Re: The Secret Book of FRC LabVIEW
 

If I am not a programmer, and I like to use LV with EV3 because it is easy to bulid and work with.
How I can began my tranining

Re: The Secret Book of FRC LabVIEW
 

First off, thank you for the book. This is our first year using LabView and it has helped us greatly. Our two primary software mentors have never used LabView before, and this book was their primary source for teaching it to the kids. I have used LabView a little bit in the past, but mostly for instrumentation control and display, never for anything complicated.


I'm trying to run through your vision example before I try and teach it to my kids. I have successfully made the distance calculations work based on the target heights, but the angle calculations are not working. I believe my problem is the blob sizes and locations are incorrect due to looking at them from an angle. This is making my calculation of the separation in x in pixels wrong, which throws everything else off. I have spent three days trying to hunt down the problem, but I'm out of ideas.

Has anyone actually earned their Image Processing Zen Master merit badge? If so, I could use some tips.

Re: The Secret Book of FRC LabVIEW
 

The distance calculation in the example uses the width of the blob as a proportion of the image size. If you scroll down on the diagram, it has some pictures and formulae to show what it is doing. By the way, this estimator works better for some field positions than for others. It is also possible to use the height of the blob, the area of the blob, or use tools like the clamps to measure things more precisely than the bounding box.

Tutorial 8 in the Getting Started also discusses this a bit, but I don't remember how much detail it goes into.

If you have other questions, I am happy to help.
Greg McKaskle

Re: The Secret Book of FRC LabVIEW
 

Without knowing exactly what you are doing... In general, the apparent size of things will be wrong, depending on where they are in the image, how your camera is pointing, etc. Suppose your camera is pointing straight at a wall a distance d away, and there is a target of height h (height in pixels hp) positioned exactly where the camera is pointing. Then that target will subtend an angle tan(theta) = h/d.

But now, if the same target is high up on the wall, it will span fewer pixels. If the line from the camera to the center of the target makes an angle phi to the horizontal, then the target will appear to be only cos(phi)*hp pixels tall. This is an approximation, because the target is also farther away, but depending on the details, that may be good enough. If you are close in, then the difference will be larger and you will have to apply Pythagoras.

Hope that helps...

Re: The Secret Book of FRC LabVIEW
 

I recently discovered some of our students were using this as a resource for self teaching in the offseason!

I have been going through it and recommend it to all looking for a good learning tool - very comprehensive - not just the basics.
This augments the nice NI tutorials incuded with Labview.
Best Labview resource I have seen since FRC Mastery .

Bumping now as maybe folks are thinking about training for the Fall.

Be nice if their was an update for the RoboRio, and maybe add new SRX CAN functionality.

Re: The Secret Book of FRC LabVIEW
 

Far be it from me to put something like this on someone's plate, but maybe a couple of knowledgeable people could go through it and suggest/add some revisions to bring it up to date, with Geoff's permission?

I've been out of the programming loop the past couple of years, but agree it's a great resource. I've been recommending it myself for some time. With some updates for newer hardware that's become available and newer versions of LabVIEW, it would continue to be a valuable tool.

Re: The Secret Book of FRC LabVIEW
 

I recently quit my job in industrial research and am now a brand new high school science teacher. While I am definitely having fun, I also have my hands completely full. (Also, the school's robotics team does Vex, so I have some other new stuff to learn.)

So....if there is someone out there who wants to take on an update of the Secret Book, I'm all for it. A student asked to do it last year, but nothing came of it. I suspect they had a robot to build, colleges to apply to, etc.

Please PM me if you think you are the person to whom the mantle should be passed...

-GN