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Turtlebot outputting over serial, but not receiving

I have a charging Turtlebot that seems to half-work. When I run roslaunch turtlebot_bringup minimal.launch, I get the Failed to open on port /dev/ttyUSB0 error that so many others have gotten. However, I also am able to open a serial connection in minicom, and I get data from the Turtlebot that seems to be battery charge information.

How is it that I have a working serial connection, but I can't seem to send commands at all? I've done all the regular chmodding and fixes to udev rules, but I'm at a loss a this point!

Using ROS hydro, if that helps.

EDIT - added the following info:

$ ls -la /dev/ttyUSB*
> crw-rw-rw- 1 root dialout 188, 0 Mar 6 21:23 /dev/ttyUSB0
$ lsusb
> ...blahblah...
> idVendor 0x0403 FTDI ltd.
> idProduct 0x6015
$ cat /etc/udev/rules.d/52-turtlebot.rules
> ATTRS{idProduct}=="6015",ATTRS{idVendor}=="0403",MODE="666",GROUP="dialout"

Asked by nckswt on 2014-03-06 17:41:22 UTC

Comments

Are you (and/or the user running the minimal.launch) in the dialout group?

Asked by William on 2014-03-07 05:01:08 UTC

Yup! Any other ideas? I'm pretty stumped =/

Asked by nckswt on 2014-03-07 15:20:23 UTC

I have no idea, where did you get the turtlebot from? Perhaps call the distributor, it may be a hardware problem, is it a Kabuki (Turtlebot2) or a iRobot Create base (Turtlebot1)?

Asked by William on 2014-03-09 08:50:12 UTC

It's a iRobot Create base. We have a few of them, and none of them have worked (tried different cables, different robots, different laptops - nothing!)

Asked by nckswt on 2014-03-10 06:38:18 UTC

Are you possibly running the node for the Kabuki base instead of the ones for the iRobot create?

Asked by William on 2014-03-10 07:01:11 UTC

I checked into that, and nope - it's the iRobot create node. I'm also trying to simply connect and send commands via minicom/screen, and it doesn't look like any data is ever sent to the iRobot when I just connect manually (though I'm still getting the battery information sent to my computer!)

Asked by nckswt on 2014-03-10 07:11:13 UTC

Strange, this is beyond my expertise to fix, it maybe that the cable you are using is not providing bidirectional communication. Maybe someone from the Turtlebot community could give some more insight...

Asked by William on 2014-03-10 07:44:37 UTC

I've made progress! I tried opening up a serial link in python and it worked – it seems like there might be an issue with minimal.launch, then. I'll look into it!

Thanks for all your help, william!

Asked by nckswt on 2014-03-10 10:22:35 UTC

Answers