why the tf.transformPoint is giving tf exception?

edit

since i was using python, i used try ... catch Exception as e: traceback.print_exc(); this is printing <module> tf2.waitForTransform(target, point.header.frame_id, rospy.Time.now(), rospy.Duration(4.0)); Exception: . canTransform returned after 4.00015 timeout was 4.

I increased duration to 5.0 , still same issue.

It looks like it is a timeout exception. Are you sure that the required transform tree is being broadcasted periodically?

It does not matter how much you increase the time if you are not publishing all the required transforms. you can check what is happening if you look at the raw tf topic

rostopic echo /tf

yes rostopic echo /tf giving output. Sorry, here is complete exception details. line 61, in <module> tf2.waitForTransform(target, point.header.frame_id, rospy.Time.now(), rospy.Duration(4.0)); Exception: Lookup would require extrapolation into the future.

Requested time 1466110388.818536997 but the latest data is at time 3101.240000000, when looking up transform from frame [base_link] to frame [wide_stereo_optical_frame]. canTransform returned after 4.003 timeout was 4.

Please edit your question to add the additional information. That way you can format it better etc. PS Please use the preformatted text mode. (highlight the block, and click the 101010 button to auto indent.