Greetings to all from team 3324 of Columbus, Ohio!
In our talking today about the control system we will be using, many (well, to be honest, most) of my fellow teammates thought that it would be a good idea to use an XBox 360 controller to control our robot since they are more familiar with it because of their gaming experience.
I tried to look up how to do it, but it generally came down to the older posts from the 2008/2009 game seasons where you still needed the USB Chicklet to control the robot using some sort of USB controller (like the XBox 360 controller). I managed to find a sample LabView project that appears to have all the code that I need and I was able to construct an alpha version of a control VI for its use. (I only really defined which button is which and all that. I’m still learning how to create my own VI and have it have both inputs and outputs.) If anyone has already gotten this to work (which I know someone has because at least one team at the Buckeye Regionals last year used them), I would be grateful for your help. If you haven’t gotten it to work, then I hope that maybe I can help you with this post and my alpha version of my VI.
The XBox controllers should work by default with the driver station for most things. Just pretend they’re normal joysticks and figure out which button numbers correspond to the buttons on the controller.
The only problem is that you can’t use the DPad, but there are some ways around that too…
I messed around with this on my home pc a while back, and I remember that the D pad is an axis, just like in other languages/whatever.
I do not remember which one it is, but it outputs the angle (such as 90, 45, 0, 180) if I remember correctly. Just make a bunch of displays and wire each to each of the available axis and see which one it is.
According to my research, you are correct, but I have no testing in this regard. The top DPad button is 0, and it goes in 45 degree increments from there until it gets back to 360 degrees/0 degrees.
EDIT:
I just talked with a teammate of mine who has an XBox 360 controller. He is going to bring it with him tomorrow so I can get some testing done with it. I’ll post the results of my testing tomorrow and, if all goes well, a finalized VI with all the controls required to use one.
0 was forward and it goes by 45 degree increments if I remember correctly. For example 0 would be forward, 45 would be holding forward and right, 90 is right, and so on. I think -1 is when you pressing nothing. Again, this is all from memory.
So it would be axis 6? I messed around with it in Java last year, and I dont remember getting anything. I’ll try again though, since it would be excellent to get working!
My team experimented with the Xbox 360 controller last year and found the following mappings (C++ code is available here, some documentation, including the following mappings, can be found here):
The buttons on the controller follow this mapping
1: A
2: B
3: X
4: Y
5: Left Bumper
6: Right Bumper
7: Back
8: Start
9: Left Joystick
10: Right Joystick
The axis on the controller follow this mapping
(all output is between -1 and 1)
1: Left Stick X Axis
-Left:Negative ; Right: Positive
2: Left Stick Y Axis
-Up: Negative ; Down: Positive
3: Triggers
-Left: Positive ; Right: Negative
4: Right Stick X Axis
-Left: Negative ; Right: Positive
5: Right Stick Y Axis
-Up: Negative ; Down: Positive
Well, I got everything to work. All buttons, all of the axes (forward, backward, left, and right): Everything.
The only problem that I have is that I have to figure out how to interface the code that I have with the Project code, but that’ll be solved in time. As I continue to go, I’ll post my VI’s here for all to see.
As of now, I hope that I can be of assistance to any team that is using LabView and is also considering using an XBox 360 controller to control their robot.
Thanks for all of your help thus far!
Austin
EDIT:
There was an error in the code that I corrected. I had accidentally set what should have been the X Axis Rotation to the Y Axis Rotation. (NOTE: X Axis Rotation is Left-Right on the right thumbstick and Y Axis Rotation is Up-Down on the right thumbstick.)
Here is the mapping that I have found out as I have listed in the VI:
X Axis: Left Thumbstick Left-Right
X Axis Rotation: Right Thumbstick Left-Right
Y Axis: Left Thumb Stick (Needs to be negated or else up-down controlls are inverted)
Y Axis Rotation: Right Thumb Stick (Needs to be negated or else up-down controlls are inverted)
Z Axis (>0): Left Trigger
Z Axis (<0): Right Trigger
1: A Button
2: B Button
3: X Button
4: Y Button
5: Left Bumper
6: Right Bumper
7: Stop/Back Button
8: Start Button
9: Left Thumbstick Button
10: Right Thumbstick Button
DPAD:
-1: No Thumbpad Button
0: North Thumbpad Button
45: North-East Thumbpad Button
90: East Thumbpad Button
135: South-East Thumbpad Button
180: South Thumbpad Button
225: South-West Thumbpad Button
270: West Thumbpad Button
315: North-West Thumbpad Button
Ok, well, in my attempts to interface my program with the FRC Project, I discovered one very important thing: This code only works on the host computer, not the cRIO.
I have started to muck around with trying to get LabView to read the controller using the WPI Joystick VIs and got some functionality. I was able to get it to read both thumbsticks in both the X and Y Axis, the triggers, and the X Axis on the thumbpad. The only downside is that, at least in my opinion, since all of those were from the six axes already built into the code, I opted to go in and modify the underlying WPI code to allow for a seventh axis (and, if it works, it will soon become more). I have no idea whether or not this will do anything nor whether I could do some serious damage to the program by modifying the VIs at such a base level.
It claims to be fully compatible and able to compiled, but I haven’t been able to actually upload it and test my extra axis. I also don’t even know if what I’m doing could help since I don’t actually know if the controller communicates over more than six axes.
If anyone could help with these modifications, I would be most grateful, and if you just want to know how to actually get LabView to read the XBox 360 controller, then I am glad that I could help you.
Austin
Included as attachments are the version of the Teleop VI that I am using to test the controller, the WPI_JoystickGet VI that I have modified to get a seventh axis, and the WPI_JoystickCache VI that actually is where I created my seventh axis in.
Hey, our team is also trying to controll our robot with an Xbox controller and we have been following your thread. We however wanted to know if you had found a way to incorporate the rumble pack in the Xbox 360 controller into the labview code. Thank you for your time.