Odom topic position.Y remains zero

[anoftc]

Hi,

We use an old (7 years old) turtlebot2 with a Kobuki base that we use for ROS education.

Recently we noticed that the same software that worked nicely before suddenly doesn't work. It turned out that the pose.pose.position values in the odom topic of the robot reported normal X values, but pose.pose.position.y always remained zero.

We visually inspected the kobuki base, saw nothing extra... Rebooted the robot, and then everything was OK, both X and Y position values were reported well into the robot's odom topic. In the past month, about 95% of the times the robot was OK, 5% of the time the Y position always remained zero.

Do you think this is a sign of some hardware problem starting to arise? What can be the cause of only the Y coordinate remaining zero??? Which component do you recommend we should exchange? Or shall we only update the firmware? Even the robot reports on bringup that the firmware is old ("1.1.4, latest is 1.2.x") ...

Thank you for your help in advance,
Yours,
Zsolt Szabó
Óbuda University NIK

[stonier]

Firmware shouldn't be a problem (and 1.2.0 is just a convenience upgrade to enable PID tuning). Also, this kobuki-base/kobuki_core#37 ensures the driver now supports both 1.1.4 and 1.2.0 without warnings.

I'm no expert on hardware, but if I was to guess, maybe a cable issue between the encoder and Kobuki's embedded board.