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Often, I'll have a lot of trouble trouble getting a robot to localize correctly. correctly. It will constantly get lost and I'll I'll spend a lot of time mucking with the the parameters for AMCL only to find that that the real culprit is the robot's robot's odometry. As such, I always run two two sanity checks to make sure that I I believe the odometry of a robot.

The first test checks how reasonable reasonable the odometry is for rotation. I open open up rviz, set the frame to "odom," "odom," display the laser scan the robot robot provides, set the decay time on that that topic high (something like 20 20 seconds), and perform an in-place in-place rotation. Then, I look at how closely closely the scans match each other on on subsequent rotations. Ideally, the the scans will fall right on top of each each other, but some rotational drift is is expected, so I just make sure that the the scans aren't off by more than a degree degree or two.

The next test is a sanity check on on odometry for translation. I'll set up up rviz the same way with the robot a few few meters away from a wall. Then, I'll I'll drive the robot straight at the wall wall and look at the thickness of the wall wall as reported by the aggregated laser laser scans in rviz. Ideally, the wall wall should look like a single scan but I I just make sure that it doesn't have a a thickness of more than a few few centimeters. If you drive a meter meter towards a wall and get scans spread spread out over half a meter though, though, something is likely wrong with the the odometry.