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.

plc/PassThrough: Unable to lookup, cache is empty?

asked 2012-08-03 03:13:58 -0600

liborw

801 ●47 ●57 ●67

Hi,

I have a problem converting a point cloud form one frame to another using plc/PassThrough filter. The problem, it seems, is that the PassThrough filter is too fast for lookup cache to fill. How can I make the filter to wait awhile for the cache to fill?

Thanks

The error message is:

[ERROR] [1343999032.826366155]: Unable to lookup transform, cache is empty, when looking up     transform from frame [/camera_depth_optical_frame] to frame [/base_link]
[ERROR] [1343999032.826482353]: [/cloud_to_baselink::computePublish] Error converting output dataset from /camera_depth_optical_frame to base_link.

edit retag flag offensive close merge delete

add a comment

1 Answer

Sort by » oldest newest most voted

answered 2012-10-21 12:26:49 -0600

tfoote

58457 ●128 ●550 ●526 http://www.ros.org/

Do you construct your TransformListener before the call and does it persist to allow it to build up it's cache? If so, do you also probably need to be robust to the cache not being full the first time, and need to let it retry for a couple cycles to let the cache fill up.

You might also want to look at using a tf::MessageFilter to hold data until transforms are available.

edit flag offensive delete link

add a comment

Question Tools

Stats

Asked: 2012-08-03 03:13:58 -0600

Seen: 542 times

Last updated: Oct 21 '12

plc/PassThrough: Unable to lookup, cache is empty? edit

1 Answer

Question Tools

Stats

Related questions

plc/PassThrough: Unable to lookup, cache is empty?