Husky A200 gmapping transform problem

Question

Hi Again,

I am trying to use Gmapping on a Clearpath Husky A200 with a Sick LMS100 laser range finder. The problem I am running into is that there is no tf from odom to base_footprint. I tried using a static_transfor_publisher to force a connection, but I have found that I will only get the first map scan and then nothing else as it appears that gmapping updates the map based on changes in the odom->base_footprint transform. Since I was using a static transform it never changes, therefore the map never updates. According to the gmapping package page on the wiki this link is usually provided by the odometry system. Anyone know why it is not being provided in this instance or how I can fix this?

Thanks

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Originally posted by Icehawk101 on ROS Answers with karma: 955 on 2013-03-25

Post score: 1

Answer 1

As far as i can see, the clearpath_husky stack does not provide any transforms out of the box. However you can get odometry messages from the husky_bringup package on the /encoder topic. These can be used as input for robot_pose_ekf or laser_scan_matcher, which both can publish the required odom(world) -> base_link transform.

In your case the laser_scan_matcher could even be used without any odometry data from the husky plattform at all. You just need to feed your laserscans into it, set ~fixed_frame to "odom" and both ~use_imu and ~use_odom to "false". Even if this odometry is far from optimal, it should give you a starting point for the gmapping usage.

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Originally posted by Ben_S with karma: 2510 on 2013-03-25

This answer was ACCEPTED on the original site

Post score: 3