Hi Eitan and Eric,
I have confirmed that the problem returns when I go back to publishing
my odometry at 20 Hz and the problem disappears when I drop it down to
10 Hz. I created two bag files under the two conditions. The first
file (by date) is at 20 Hz and you can see the robot oscillating all
around one of the goals while the angular velocity exceeds the set limit
of 1.0. The second bag file was collected with odometry running at 10
Hz and the robot's behavior was flawless. I should point out that I am
connecting to the Serializer board on the robot using (non-Pro) XBee
radios while running ROS on my PC. The radios are communicating at
19200 baud and are about 10-20 feet apart during testing.
I placed the two bag files at the link below:
http://www.pirobot.org/code/debug/
Let me know if you need any of my source files as well as I would be
happy to post them.
Thanks!
Patrick Goebel
Behavioral Sciences
Stanford University
> Just a brief update,
>
> I had stage publish odometry information at 20.0Hz and could not get the
> commanded velocity to go outside the limits. So, I'm still unable to
> reproduce the problem.
>
> -Eitan
>
> On Mon, Sep 27, 2010 at 3:36 PM, Eitan Marder-Eppstein <
> eitan@willowgarage.com <mailto:eitan@willowgarage.com>> wrote:
> /
> > Patrick,
> >
> > First off, I'm glad things are working, but I'm also surprised that the
> > rate at which odometry publishes has anything to do with the
> > base_local_planner respecting maximum velocity limits. I'll try
> upping the
> > rate that stage publishes odometry information to see if I can
> reproduce
> > this, but our robot also publishes odometry information at 30Hz and,
> much
> > like Eric, we don't see this problem. Also, like Eric asked, I'd
> love to
> > know if changing the odometry rate back to what it was reliable
> causes this
> > failure... I'd just really like to track down what's going on. Its
> just a
> > really strange solution to the problem.
> >
> > Thanks a bunch,
> >
> > Eitan
> >
> >
> > On Mon, Sep 27, 2010 at 3:24 PM, Eric Perko <wisesage5001@gmail.com
> <mailto:wisesage5001@gmail.com>>wrote:
> >
> >> Patrick,
> >>
> >> Can you confirm that changing just your odometry publishing rate
> back to
> >> 20Hz causes the failure? The last person with a similar problem was
> unable
> >> to reproduce when he changed his lidar rate back to what it was
> previously.
> >> Also, I'm a bit surprised that lowering your odometry rate fixed
> things - I
> >> publish odometry at 50Hz and don't see this sort of problem...
> >>
> >> - Eric
> >> /
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