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2017-01-13 03:53:53 -0500 answered a question why the time stamp of the message is later than the rosbag time?

It turns out to be I'm restarting the rosbag play again but the debugging process is not restarted.

2017-01-13 03:53:04 -0500 commented question why the time stamp of the message is later than the rosbag time?

It turns out to be I'm restarting the rosbag play again but the debugging process is not restarted.

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2017-01-11 20:03:26 -0500 asked a question why the time stamp of the message is later than the rosbag time?

I'm debugging my code with rosbag replay. In my code, I did tf transform like this:

tf.transformPose(target_frame, input_pose, output_pose);

Sometimes, there's an exception thrown, which read:

"Lookup would require extrapolation into the future.  Requested time 1484037737.206813097 but the latest data is at time 1484037724.492085834, when looking up transform from frame [odom] to frame [map]"

I checked in the debugger, and found the time stamp of the message input_pose is later than the rosbag time:

p input_pose.stamp_ 
$1  sec = 1484037737, nsec = 206813097
p ros::Time::now()
$2  sec = 1484037724, nsec = 918256570

Also, the rosbag play console shows:

 [PAUSED]   Bag Time: 1484037724.967132

The commands I used to run the rosbag is

rosbag play --clock --pause bagfile.bag

And the param use_sim_time is already set to true:

$rosparam get use_sim_time
true

Could anyone please help with this problem? Thanks!

2016-08-01 03:17:07 -0500 answered a question What's the rational behind laser_filters/ScanShadowsFilter?

Maybe you want to use LaserScanAngularBoundsFilter instead of ScanShadowFilter. ScanShadowFilter removes laser data points which satisfies the following conditions : for all p1, if exists point p2 in (p1 -window, p1 + window), so that (∠O P1 P2) < minAngular, or (∠O P1 P2) > maxAngular, then, all datapoint in (p1 - neigbor, p1 + neigbor) will be removed. Where O means the origin of the laser.

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2015-12-02 21:43:02 -0500 commented question how to launch pr2 simulation in jade

ok, thanks

2015-11-30 09:01:43 -0500 answered a question how to launch pr2 simulation in jade

why I can't see this question in the ask list? and it says 'this post is awaiting moderation', what does that mean? what do I need to do to moderate it?

2015-11-30 09:01:42 -0500 asked a question how to launch pr2 simulation in jade

I followed the tutorial of pr2 simulation: http://wiki.ros.org/pr2_simulator/Tut...

roslaunch gazebo_ros empty_world.launch

this command is fine, the gazebo window shows an empty world. while run the following command :

roslaunch pr2_gazebo pr2.launch

an error occurs:

[pr2.launch] is neither a launch file in package [pr2_gazebo] nor is [pr2_gazebo] a launch file name

There's no package named 'pr2_gazebo' in jade, I tried to find it with apt-get:

aptitude search pr2

there are 6 packages in jade related to pr2:

ros-jade-pr2-common
ros-jade-pr2-dashboard-aggregator
ros-jade-pr2-description
ros-jade-pr2-machine
ros-jade-pr2-mechanism-msgs
ros-jade-pr2-msgs

none of them contains pr2.launch. So, how can I run simulation for pr2 in jade?