Robot "bucking" while driving in reverse

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A typical case for this to happen is when there is still some teleop node running somewhere when starting autonomous navigation.

@Pyo I suspected this might be the case but didn’t immediately think of how to check. Thanks for tip. @felixwidmayer I suspect the same. I think I checked that I killed it but there might have been a zombie teleport process that was not fully killed.

@Pyo @felix-widmaier - I see "bucking" behavior when teleoping in reverse, with no other nodes or packages running. So the theory was good, it doesn't; really seem to apply. Rosnode list, shows this: rosout, rqt_gui_py_node_4440, turtlebot3_core, turtlebot3_lds, turtlebot3_diagnostics.Thoughts??

Perhaps a screenshot of rqt_graph would be more informative. Be sure to create it when you're actually observing the behaviour in the video.

It's very likely that there is a node publishing zero-Twists.

I will try but I am almost 100% sure because I looked at the graph and saw no-one publishing on cmd_vel.

I am suspecting that it is a weight distribution problem because it seems to change if I slide the battery around a little. It doesn't solve it but it seems more or less severe

Could also be there is no proper ramp-up of teleop velocity commands. I already commented on your #q300208 about how the TB2 addresses that.

@gvdhoorn by all means you've been super helpful and I am grateful! The teleop code supplied (and I looked at the source) definitely does do a rampup. I assume it's correct but I can investigate to make sure it does what is stated.

re: investigate: that may be a bit much at this stage.

I would take a look at some of the msgs on the /cmd_vel topic (or whatever is being used on the TB3). Just use rostopic echo /cmd_vel when the robot is standing still (replace with appropriate topic). Then compare when teleopping.