murdock's profile - activity

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

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.

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

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

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.

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

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

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

Nope, not using clock. Will check it out.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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?

Have you figured it out?

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