Attention: Answers.ros.org is deprecated as of August the 11th, 2023. Please visit robotics.stackexchange.com to ask a new question. This site will remain online in read-only mode during the transition and into the foreseeable future. Selected questions and answers have been migrated, and redirects have been put in place to direct users to the corresponding questions on Robotics Stack Exchange. Additional details are available here.

Trajectory filters and joint limits over PI

asked 2011-03-13 15:06:49 -0500

arebgun

2121 ●7 ●22 ●43 http://www.cs.arizona....

Hello folks,

I ran into trouble with some of the assumptions that trajectory filters make. I have a servo motor that can do 250 degrees of travel, e.g. it's not a continuous servo. I would like to position it in such a way that the joint limits are, for example, -40 to 210 degrees. The problem is that if some trajectory wants to put this joint at anything over 180 degrees it will want to wrap around, but servo won't be able reach that position for obvious reasons. Is there a way around that?

edit retag flag offensive close merge delete

add a comment

1 Answer

Sort by » oldest newest most voted

answered 2011-03-13 15:42:00 -0500

kalakris

529 ●3 ●5 ●7 http://www-clmc.usc.ed...

There is at least one bug that I found in planning_environment related to this. Here is a link to the ticket and the patch: https://code.ros.org/trac/ros-pkg/ticket/4741

Although the patch is for cturtle, a quick check confirms that the bug may still exist. Also, I do not use the standard trajectory filters in my use case, so your mileage may vary.

edit flag offensive delete link

Comments

Mrinal, you are right, that ticket describes the problem I am having and it looks like the attached patch should fix it. I would need to fix a bunch more packages for this to work properly. I was wondering why motion planner thinks a joint angle was at -3.00 radians when it was definitely over +3.00, that would be why :)

arebgun ( 2011-03-13 15:53:48 -0500 )edit

add a comment

Question Tools

1 follower

Stats

Asked: 2011-03-13 15:06:49 -0500

Seen: 602 times

Last updated: Mar 13 '11

Trajectory filters and joint limits over PI edit

1 Answer

Comments

Question Tools

Stats

Related questions

Trajectory filters and joint limits over PI