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2019-03-20 10:54:24 -0500 asked a question UWSim /g500/pose doesn't echo anything

UWSim /g500/pose doesn't echo anything Hello, I want to compare my algorithm's tx ty tz qx qy qz qw to the groundtruth

2019-03-20 10:12:39 -0500 commented question the message of the topic '/g500/pose' and '/uwsim/girona500_odom' is not correct

When I run $ rostopic echo /g500/pose I dont receive any messages.

2019-03-20 09:24:48 -0500 received badge  Popular Question (source)
2019-03-14 08:12:07 -0500 marked best answer /tf sends messages at different timestamp

I have a /tf message that seems to send messages at different timestamps. I added comments "// Look here" to highlight the stamps in secs and Im mostly intrigued by the one with the comment "// Look here !!" as the time stamp in secs has absolutely different timestamp. However, the next after that one follows the the pattern as the majority.

image description

Why does this happen?

--
transforms: 
- 
header: 
  seq: 0
  stamp: 
    secs: 1305031234        // Look here
    nsecs: 763107844
  frame_id: /kinect
child_frame_id: /openni_camera
transform: 
  translation: 
    x: -0.0112272525515
    y: 0.0502554918469
    z: -0.0574041954071
  rotation: 
    x: 0.129908557896
    y: -0.141388223098
    z: 0.681948549539
    w: 0.705747343414
- 
header: 
  seq: 0
  stamp: 
    secs: 1305031234           // Look here
    nsecs: 763107844
  frame_id: /world
child_frame_id: /kinect
transform: 
  translation: 
    x: 1.28183615112
    y: 0.60716934967
    z: 1.60902340698
  rotation: 
    x: -0.226407331155
    y: -0.209261051914
    z: 0.662704621347
    w: 0.682474993971
 ---
 transforms: 
- 
  header: 
    seq: 0
    stamp: 
    secs: 1551776935     // Look here   !!!
    nsecs: 528851222
  frame_id: world
  child_frame_id: camera_pose
transform: 
  translation: 
    x: 0.0543486074629
    y: -0.0490532501685
    z: -0.083467717153
  rotation: 
    x: 0.0249910632545
    y: -0.369232593093
    z: 0.0535471565154
    w: 0.927456436165
---
transforms: 
- 
header: 
  seq: 0
  stamp: 
    secs: 1305031234                 // Look here
    nsecs: 773104542
  frame_id: /kinect
child_frame_id: /openni_camera
transform: 
  translation: 
    x: -0.0112272525515
    y: 0.0502554918469
    z: -0.0574041954071
  rotation: 
    x: 0.129908557896
    y: -0.141388223098
    z: 0.681948549539
    w: 0.705747343414
2019-03-14 08:12:02 -0500 answered a question /tf sends messages at different timestamp

I looked up this answer. Just by setting the use_sim_time alone didnt work in the beginning. I completely stopped the

2019-03-14 07:37:52 -0500 commented question /tf sends messages at different timestamp

@gvdhoorn, setting up --clock didnt work. I get the same issue.

2019-03-07 05:17:00 -0500 received badge  Notable Question (source)
2019-03-05 08:10:39 -0500 commented question /tf sends messages at different timestamp

Nope, not using clock. Will check it out.

2019-03-05 06:36:01 -0500 received badge  Popular Question (source)
2019-03-05 05:49:01 -0500 commented question /tf sends messages at different timestamp

@gvdhoorn, what do you mean by live nodes? @EdwardNur, updated my question with the tree,

2019-03-05 05:48:29 -0500 edited question /tf sends messages at different timestamp

/tf sends messages at different timestamp I have a /tf message that seems to send messages at different timestamps. I ad

2019-03-05 05:47:05 -0500 commented question /tf sends messages at different timestamp

@gvdhoorn, what do you mean live nodes? @EdwardNur, updated my question with the tree,

2019-03-05 03:18:22 -0500 edited question /tf sends messages at different timestamp

/tf sends messages at different timestamp I have a /tf message that seems to send messages at different timestamps. I ad

2019-03-05 03:17:34 -0500 asked a question /tf sends messages at different timestamp

/tf sends messages at different timestamp I have a /tf message that seems to send messages at different timestamps. I ad

2019-02-27 04:54:54 -0500 commented question Transform camera pose to world interpretation

https://vision.in.tum.de/rgbd/dataset/freiburg1/rgbd_dataset_freiburg1_rpy-groundtruth.txt This is the ground truth data

2019-02-27 02:57:52 -0500 received badge  Popular Question (source)
2019-02-27 02:17:11 -0500 commented question Transform camera pose to world interpretation

I looked at the ground truth data of the rosbag that I was trying to get the camera_pose. I see that the ground truth is

2019-02-26 07:25:34 -0500 commented question Transform camera pose to world interpretation

Do you mean this http://www.optique-ingenieur.org/en/courses/OPI_ang_M04_C01/co/Contenu03.html ? How can I even check if

2019-02-26 07:24:49 -0500 commented question Transform camera pose to world interpretation

Do you mean this http://www.optique-ingenieur.org/en/courses/OPI_ang_M04_C01/co/Contenu03.html ?

2019-02-26 05:35:16 -0500 edited question Transform camera pose to world interpretation

Transform camera pose to world interpretation Hello, I read the tutorial on transforms. I followed the step Checking th

2019-02-26 03:30:16 -0500 edited question Transform camera pose to world interpretation

Transform camera pose to world interpretation Hello, I read the tutorial on transforms. Following step Checking the res

2019-02-26 03:16:55 -0500 edited question Transform camera pose to world interpretation

Transform camera pose to world interpretation Hello, I read the tutorial on transforms. Following step Checking the res

2019-02-26 03:16:14 -0500 commented question Transform camera pose to world interpretation

How do I get the pose of the camera in the world frame?

2019-02-26 02:51:15 -0500 edited question Transform camera pose to world interpretation

Transform camera pose to world interpretation Hello, I read the tutorial on transforms. Following step Checking the res

2019-02-26 02:50:33 -0500 asked a question Transform camera pose to world interpretation

Transform camera pose to world interpretation Hello, I read the tutorial on transforms. Following step Checking the res

2019-02-25 09:05:23 -0500 marked best answer LSD-SLAM virtual camera calibration

Hello,

I have recorded some actions using $rosbag record within the virtual simulator called UWSim. I am trying right now to make it work with lsd_slam.

My camera topic is /g500/camera1 Therefore, I ran lsd_slam as follow:

 rosrun lsd_slam_core live_slam image:=/g500/camera1 camera_info:=/camera_info

Now of course I am getting a message saying "WAITING for ROS camera calibration!". I have found someone previously asking how to calibrate virtual camera, however the answer was there is no need. Then what kind of calibration data I should send?

2019-02-23 11:47:08 -0500 received badge  Popular Question (source)
2019-02-23 11:23:25 -0500 commented question Visualize lsd_slam point cloud with rviz

Have you figured it out?

2019-02-22 08:45:44 -0500 edited answer LSD-SLAM virtual camera calibration

Managed to solve it. I calculated the camera parameters and this is what Ive got (I calculated these by following this

2019-02-22 08:45:00 -0500 edited answer LSD-SLAM virtual camera calibration

Managed to solve it. I calculated the camera parameters and this is what Ive got (I calculated these by following this

2019-02-22 08:43:35 -0500 answered a question LSD-SLAM virtual camera calibration

Managed to solve it. I calculated the camera parameters and this is what Ive got: 0.804 1.07 0 0 0 320 240 none 320 2

2019-02-22 07:26:58 -0500 edited question LSD-SLAM virtual camera calibration

LSD-SLAM virtual camera calibration Hello, I have recorded some actions using $rosbag record within the virtual simula

2019-02-22 07:26:32 -0500 asked a question LSD-SLAM virtual camera calibration

LSD-SLAM virtual camera calibration Hello, I have recorded some actions using __$rosbag record__ within the virtual si

2019-02-22 05:49:45 -0500 commented answer Absolute position of girona500 in uwsim

How did you solve it? I am trying to make it work with teleop.

2019-02-22 05:04:06 -0500 commented question SLAM for AUVs in underwater simulator

Yes, I have installed UWSim and have been trying to make it work, but to no avail. I really enjoyed how you can swap di

2019-02-22 04:49:38 -0500 received badge  Popular Question (source)
2019-02-22 03:20:32 -0500 edited question SLAM for AUVs in underwater simulator

SLAM for AUVs in underwater simulator Hello, I would like to make ORB- or LSD-SLAM (or any other) technique work with o

2019-02-22 03:16:51 -0500 asked a question SLAM for AUVs in underwater simulator

SLAM for AUVs in underwater simulator Hello, I would like to make ORB- or LSD-SLAM (or any other) technique work with o

2019-02-22 02:55:03 -0500 commented question simulation environment of underwater robot

Have you ever managed to implement SLAM for AUVs?

2019-01-15 08:54:36 -0500 received badge  Famous Question (source)
2019-01-15 08:53:26 -0500 asked a question UWSim vs UUV Simulator

UWSim vs UUV Simulator Hello, I want to create an AUV that is going to be able to perform the default implemented under

2018-08-19 09:28:46 -0500 marked best answer Robot localization with AMCL and EKF

Hello,

I have been following an example here with jackal. My goal so far was to understand how AMCL works. However, in his example he uses ekf_localization and AMCL is just a tool to output cloud with the current robot's position. Here is a rqt_graph when I ran the localization example (which is running gazebo, amcl and rviz) . I thought that AMCL was a separate algorithm for localization and it did not need anything else. What am I missing? Why they are using both EKF and AMCL?

Screenshot of rqt_graph: http://tinyurl.com/z73k3nj

2018-07-19 09:31:26 -0500 marked best answer Why AMCL requires to subscribe to /initialpose topic?

AMCL is supposed to solve global localization problem, which means that the robot doesnt know its initial pose. I found this answer in this forum, but I did not understand it. Does it mean that I am providing it initial pose if its subscribing to it?

initialpose (geometry_msgs/PoseWithCovarianceStamped)
Mean and covariance with which to (re-)initialize the particle filter.

EDIT Alright, so apparently it is a violation of global localization problem. Thank you, Martin.

How does one avoid giving initial pose? I need to solve a global localization problem but this is cheating now if I say I use AMCL and provide everything robot needs.