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Hi,

there are many questions here about that error indifferent scenarios. I am using slam_karto and groovy, but the code in goal_functions.cpp has not changed much.

I also found that the exception is thrown in navigation/base_local_planner/src/goal_functions.cpp:transformGlobalPlan() - yet for me, tf.lookupTransform (line 110) is ok, but tf.transformPose (line 116) fails. My tf-tree is /map -> /odom -> /base_footprint. /odom is published with an average delay of 90ms, while /base_footprint has a delay of 35ms. Debugging the code shows that tf.transformPose is requested to transform the pose to /map at now()-35ms. That fails, since the /odom transformation is older, and tf does not extrapolate so far into the future.

My solution was to change the tf.transformPose call, such that it takes the most recent time: tf.transformPose(plan_pose.header.frame_id, ros::Time(0), global_pose, global_pose.frame_id_, robot_pose);

While this works, I wonder how things should behave in the original code. Are delays between the different frames not accepted? Or does the extrapolation usually work, for whatever reason? Maybe someone who runs move_base successfully can comment on that.

@robotiqsguy: Could you verify where exactly the exception is triggered in your case? Also, what delays do you see for your frames, if you run rosrun tf tf_monitor?

Best Regards!

Hi,

there are many questions here about that error indifferent in different scenarios. I am using slam_karto and groovy, but the code in goal_functions.cpp has not changed much.

I also found that the exception is thrown in navigation/base_local_planner/src/goal_functions.cpp:transformGlobalPlan() - yet for me, tf.lookupTransform (line 110) is ok, but tf.transformPose (line 116) fails. My tf-tree is /map -> /odom -> /base_footprint. /odom is published with an average delay of 90ms, while /base_footprint has a delay of 35ms. Debugging the code shows that tf.transformPose is requested to transform the pose to /map at now()-35ms. That fails, since the /odom transformation is older, and tf does not extrapolate so far into the future.

My solution was to change the tf.transformPose call, such that it takes the most recent time: tf.transformPose(plan_pose.header.frame_id, ros::Time(0), global_pose, global_pose.frame_id_, robot_pose);

While this works, I wonder how things should behave in the original code. Are delays between the different frames not accepted? Or does the extrapolation usually work, for whatever reason? Maybe someone who runs move_base successfully can comment on that.

@robotiqsguy: Could you verify where exactly the exception is triggered in your case? Also, what delays do you see for your frames, if you run rosrun tf tf_monitor?

Best Regards!

Hi,

there are many questions here about that error in different scenarios. I am using slam_karto and groovy, but the code in goal_functions.cpp has not changed much.

I also found that the exception is thrown in navigation/base_local_planner/src/goal_functions.cpp:transformGlobalPlan() - yet for me, tf.lookupTransform (line 110) is ok, but tf.transformPose (line 116) fails. My tf-tree is /map -> /odom -> /base_footprint. /odom is published with an average delay of 90ms, while /base_footprint has a delay of 35ms. Debugging the code shows that tf.transformPose is requested to transform the pose to /map at now()-35ms. That fails, since the /odom transformation is older, and tf apparently does not extrapolate so far into the future.

My solution was to change the tf.transformPose call, such that it takes the most recent time: tf.transformPose(plan_pose.header.frame_id, ros::Time(0), global_pose, global_pose.frame_id_, robot_pose);

While this works, I wonder how things should behave in the original code. Are delays between the different frames not accepted? Or does the extrapolation usually work, for whatever reason? Maybe someone who runs move_base successfully can comment on that.

@robotiqsguy: Could you verify where exactly the exception is triggered in your case? Also, what delays do you see for your frames, if you run rosrun tf tf_monitor?

Best Regards!