Flavio90's profile - activity

So you mean that i should publish the transformation from odom to base_link in the same /tf topic which is published by gmapping?

Hi all, i have this problem using the gmapping node. I'm trying to use gmapping to read data from a laser scanner and build a map . I know that gmapping needs two transformations, the first from map to odom, and the last from odom to base_link (which represents the movements of the robot, it's odometry, right?). I also know, reading its wiki page, that the gmapping node subscribes the /laser_scan topic (data from laser scanner) and the /tf topic (transformations). My problem is that the gmapping node itself publishes the /tf topic with the transformation from map to odom. So, how can I give the odom to base_link transformation to gmapping, if the /tf topic is already published??

Thanks a lot for your help, Flavio

Actually, that parameter is already set to 1, but che override doesn't work. Do you have other suggestions?

Hi guys, i'm using a pixhawk with ardurover inside. I'm trying to use a ROS node to override the RC channels and drive my rover, through the telemetry. Earlier I managed this problem and i was able to drive the motors of the rover from a ROS node, but now it is not working anymore. I see the right values both on the rc_override and rc_in topics, but not on the rc_out topic, so the rover doesn't move. Do I have to check the GCS_SYSTEM_ID or something similar? Actually, it is already set to 255 (1). Is there a specific "flight mode" that allows the override? I don't know anymore what to do.

Thanks a lot for your help, Flavio

Hi guys,

I’m trying to use rviz to read this laser scanner sampled data ( http://classes.engineering.wustl.edu/... ) , using rosbag play. I add a display that reads the /base_scan topic and i visualize data on the grid, but in the terminal i get this error: [ WARN] [1434533618.305097862]: MessageFilter [target=map ]: Dropped 100.00% of messages so far. Please turn the [ros.rviz.message_notifier] rosconsole logger to DEBUG for more information. What does it mean and how could i solve it? Then, i’d like to use the gmapping node to read the same sample data from the /base_scan topic. When i launch the gmapping node i get this error: [ WARN] [1434533924.754354892]: MessageFilter [target=odom ]: Dropped 100.00% of messages so far. Please turn the [ros.gmapping.message_notifier] rosconsole logger to DEBUG for more information. I noticed that the gmapping node needs also to read the /ft topic to work properly, but that topic is not published when i run rosbag play Mapping1.bag, so it’s empty. Is it a problem? How can i manage it?

Thank you very much, Flavio

I’m trying to use rviz to read this laser scanner sampled data ( http://classes.engineering.wustl.edu/... ) , using rosbag play. I add a display that reads the /base_scan topic and i visualize data on the grid, but in the terminal i get this error: [ WARN] [1434533618.305097862]: MessageFilter [target=map ]: Dropped 100.00% of messages so far. Please turn the [ros.rviz.message_notifier] rosconsole logger to DEBUG for more information. What does it mean and how could i solve it? Then, i’d like to use the gmapping node to read the same sample data from the /base_scan topic. When i launch the gmapping node i get this error: [ WARN] [1434533924.754354892]: MessageFilter [target=odom ]: Dropped 100.00% of messages so far. Please turn the [ros.gmapping.message_notifier] rosconsole logger to DEBUG for more information. I noticed that the gmapping node needs also to read the /ft topic to work properly, but that topic is not published when i run rosbag play Mapping1.bag, so it’s empty. Is it a problem? How can i manage it?