zhiping's profile - activity

Hi to all,

From my understanding, i believe that the move_base will ignore the unknown pixel from the map during the path finding. Is it possible to set any parameter in move_base to remove this action so that i can set unknown pixel as goal?

Preview of my map

With thanks, Zhiping

Hi to all,

I'm currently trying to simulate the behavior of my robot using STAGE simulation but the tf timing from STAGE is too slow with a time interval of 13 x10^6 second. I tried to overcome this problem by overwrite the tf using the static transform publisher but the time become negative with this warning:

TF_OLD_DATA ignoring data from the past for frame /base_footprint at time 12.6 according to authority /Stage_Node

How should i approach this problem?

With thanks, Zhiping

previous message link

Thanks for the reply.

My main intention is to add Slam ability to my robot.

I tried to use gmapping to replace the map_server to produce a concurrent updating map. But the calculation is too demanding on my laptop. I'm thinking whether i can make a simplified Slam to reduce the computational demand on my laptop.

Currently when i published an empty map, which contains all unknown pixels, from my "/map" (nav_msgs::Occupany_msgs) topic, the map is not shown in rviz and the tf containing the odom to map is not created.

Is there any easier ways to solve it?

Sorry to trouble your guys.

With thanks, Zhiping

laptop specification

core2 duo

Hi Zhiping, you may not be using the right versions. In particular, if you follow the rosinstall directions given on http://www.ros.org/wiki/topological_navigation you shouldn't have any dependency problems. Also, the camera is not needed for this stack — it just assumes a horizontal laser range finder.

Hi to all,

I'm trying to test the Topological_navigation but i encountered some dependencies problem. Apparently, one of the stacks known as graph_mapping_utils is not available in the graph_mapping package but is required by the topological_navigation package. How should i solve it?

Can i also classify whether usage of the camera is the only source to obtain information from the surrounding by the topological_navigation?

Thank for your time

With regards, Zhiping

Zhiping,

From the videos you posted it looks like the navigation stack isn't receiving laser data from stage correctly. No obstacles, raw or inflated, are showing up in the costmap. Is navigation giving you any errors? Are you sure that you've configured navigation to run with the correct topic name for the laser? Is there anything notably different in the topics provided by the p2os driver versus stage that would prevent the same configuration files from working in both scenarios?

Hope all is well,

Eitan

Hi Zhiping,

you can set the parameter allow_unknow of navfn to true. Then unknown points of the global costmap are possible goal positions (and possible points in the global plan). If you used this tutorial to set up navigation then adding the following line to move_base.launch should do the trick:

<param name="navfn/allow_unknown" value="true"/>

<node pkg="move_base" type="move_base" respawn="false" name="move_base" output="screen">
...
</node>

But make sure that the wanted goal position is within the bounds of your global costmap. If the goal is very close to an obstacle (in range of the inflated obstacle points) navfn will regard it as not reachable - at least in cturtle, may be this has changed in diamondback.

Regards, Sabrina

This is a suggested solution for my problem. Basically, i think i don't need to set the navfn/allow_unknown because the default value is true and unknown_cost_value but i need to set the static map in the global costmap to false because i'm running on gmapping

Hi,

I trying to run Stage together with move_base and either gmapping or map_server+amcl but i realized that inflation message is not reflected on rviz although the message is received as shown in these video: Gmapping and Map_server.

If I run the program in actual environment (replaced Stage with laser driver and p2os_driver), the inflated appeared with the Map_server combination but not in Gmapping.

How should i handle this problem? Thanks for the assistance

With regards,

Zhiping