Ask Your Question
0

local_costmap global frame

asked 2012-07-25 02:36:33 -0500

pkohout gravatar image

hi, i do not have a odom frame and wanna use a local costmap. my question is what should i use instead ? my tf tree is /map-> Nav -> Base_footprint -> base_stabilized -> base_link i do not have any idea in all tutorials and in the doku the /odom is used... what can i use instead ?

edit retag flag offensive close merge delete

Comments

What is Nav?

Lorenz gravatar image Lorenz  ( 2012-07-25 02:44:15 -0500 )edit

1 Answer

Sort by ยป oldest newest most voted
1

answered 2012-07-25 02:55:15 -0500

Lorenz gravatar image

The costmap needs to be in a fixed frame, i.e. frames that do not move in the world. Normally, only map and odom are fixed frames and since you do not have odom, using map should be fine.

The reason why odom is used in map is that map can "jump" because of the particle filter based localization algorithm. If that happens, obstacles get sort of blurred because different cells are set in the costmap. Odometry is continuous, i.e. no jumps can happen and the costmap isn't blurred.

edit flag offensive delete link more

Comments

ok thanks, now i understand that all a little bit more. I use hector quadrotor so i do not know what /nav is exactly but i was watching in rviz an /nav is fixed...i do not move with the rest...should i use /nav or /map ? i have read in other questens that /nav is the odom frame ...is this possible ?

pkohout gravatar image pkohout  ( 2012-07-25 03:04:38 -0500 )edit

You should probably read this: http://www.ros.org/reps/rep-0105.html

joq gravatar image joq  ( 2012-07-26 05:47:03 -0500 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

Stats

Asked: 2012-07-25 02:36:33 -0500

Seen: 1,006 times

Last updated: Jul 25 '12