Yes I understand...I need to look into the problem more carefully Monday.. My thoughts are right now to put a try and catch in for the exception and to take another look at the raw nxt stream and see if there is anything I missed the first time I stumbled upon this problem.. If you want to work on it some more try looking at usbsock.py in nxt_python you can set debug to True and look at the data coming over the wire. -Melonee On Aug 8, 2010, at 4:49 AM, Max B wrote: > You say this happens periodically, but for me, it happens almost every time I run nxt_ros. I have set nxt_ros to respawn in the launch file, and it just keeps respawning. I applied the fix noted in Issue 5 on the nxt-python bug tracker, but it provided no help either. > > From, > Max > > On Sat, Aug 7, 2010 at 6:08 PM, Melonee Wise wrote: > This is a problem in the underlying driver in nxt_python... It occurs when the I2C bus is pulled too quickly by the python library... I will look more into a more permanent fix on monday morning since I don't have a brick at home. For now if it only happens periodically set nxt_ros respawn in your launch file.. > > -Melonee > > On Aug 7, 2010, at 2:34 PM, Max B wrote: > > > Hello, > > I am using cturtle from the Ubuntu Lucid repositories, with the svn version of the nxt stack. I am running Ubuntu Lucid x64 with kernel 2.6.32-generic. I have an NXT controller, and I am trying to use it with ROS. I have an ultrasonic sensor configured for use on the robot. When I run nxt_ros with bluetooth, I get the error "nxt.error.I2CError: ls_get_status timeout" when it is setting up the sensors, and nxt_ros dies. When I use USB, I get the error "usb.USBError: No error" and nxt_ros dies. What can I do to fix this? If I comment out the ultrasonic sensor from the yaml file (and just leave two motors and a gyro), the process runs just fine. > > From, > > Max > > _______________________________________________ > > ros-users mailing list > > ros-users@code.ros.org > > https://code.ros.org/mailman/listinfo/ros-users > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users