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2021-08-18 09:54:53 -0600 received badge  Nice Answer (source)
2020-06-03 17:07:36 -0600 commented question commands of catkin tools giving errors

@gvdhoorn, interesting, I'm not getting the same results even after pulling the latest docker image.

2019-10-05 19:16:31 -0600 commented question Velodyne sometimes error when launch the viewing data file

You should post the actual warning itself. i.e. a copy of your console

2019-06-17 08:22:37 -0600 answered a question Autonomous Navigation using lidar and hector slam?

For your robot to accurately control itself and follow the path it will invariably need to do localization or have a dec

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2019-06-17 08:18:54 -0600 commented answer Google Cartographer 3D map for localization

Please mark this answer as accepted or add your own answer for future users.

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2019-06-15 15:16:08 -0600 commented answer Google Cartographer 3D map for localization

Your entire problem is self inflicted. You localize in 3D and navigate in 2D. Why don't you make your dimensions match?

2019-06-15 13:27:58 -0600 answered a question Generating 3D Map from PointCloud Data

This will be a lot of work so make sure it is worth it. Import your point cloud into Meshlab or CloudCompare and gene

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2019-06-15 13:17:28 -0600 answered a question Google Cartographer 3D map for localization

You should use pbstream_map_publisher and/or occupancy_grid_node to create the occupancy grid. If you are running pure l

2019-06-15 13:12:11 -0600 answered a question SLAM with multiple range finders

In theory it should be possible, if you assume your world is basically 2D then you could project on the xy plane your ra

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2019-06-15 13:04:45 -0600 commented question Generating 3D Map from PointCloud Data

Define what you mean by "map". For a lot of people, having a point cloud representation of the environment would be a ma

2019-06-10 21:35:23 -0600 edited answer if condition for approximate time subscriber

I don't think there is a specific way to do that using the existing sync policies. To handle your case you would have to

2019-06-10 21:33:32 -0600 commented answer if condition for approximate time subscriber

It's impossible to clearly answer your question, you will have to figure out how precise of a solution you want on your

2019-06-09 16:17:04 -0600 answered a question if condition for approximate time subscriber

I don't think there is a specific way to do that using the existing sync policies. To handle your case you would have to

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2019-06-09 15:58:11 -0600 commented answer image_proc needs one camera_info for every image !?

I hadn't thought about that. The option @gvdhoorn suggest is probably the best one.

2019-06-08 18:52:38 -0600 answered a question rosbag replay error (use sim time problem)

This can be caused by a variety of reasons which only you can really debug. I would suggest trying the following: rospa

2019-06-08 18:48:05 -0600 answered a question image_proc needs one camera_info for every image !?

While true, on the driver side you don't know when the application will start listening on the messages so you should ju

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2019-06-08 18:33:11 -0600 answered a question What is the pixel disparity of rtabmap? Want to

Pixel disparity is unrelated to rtabmap. If you want to follow that formula then you will need to retrieve the intrinsic

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2019-06-08 18:28:08 -0600 answered a question Autonomous outdoor obstacle avoidance using LiDAR

I don't see the problem here. If you want to avoid obstacles, then by definition you are moving. If you are moving then

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2019-04-03 10:58:14 -0600 commented answer Where is magnetometer measurements in the IMU messages

For those wondering the same thing, sometimes IMUs will not give the magnetic field but rather the magnetic vector. If y

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2016-06-20 23:08:56 -0600 commented question hector_slam vs gmapping?

I don't think anyone other than you can answer this question. You would need to first define what your performance metric is (speed, accuracy, map quality, ...) before trying to find how to compare the two.

2016-05-05 10:32:22 -0600 commented answer Camera_info for a camera publishing already rectified images

Thanks!

For the second part of your answer, I did try but after the second rectification everything looks a lot worse .

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2016-05-02 22:02:02 -0600 asked a question Camera_info for a camera publishing already rectified images

I have a camera which gives me images which are already rectified. I'm writing the ROS driver for it and I'm wondering what I should do with the camera_info message. Should I :

  • Calibrate the camera and publish the intrinsic parameters in the camera_info message
  • Calibrate the camera and publish the projection matrix but set the distortion parameters to 0
  • Not calibration and set all the camera_info parameters to 0

For the record, I do not have access to the prerectified image, only the final result.

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2016-03-31 15:20:09 -0600 commented question Rosbag and timestamp received vs timestamp published

Answer accepted and question closed!

2016-03-31 15:19:19 -0600 marked best answer Rosbag and timestamp received vs timestamp published

I can't find it anymore but I seem to recall reading somewhere that when you record a rosbag, the timestamp encoded to the message is the time at which the message was received by the rosbag record process instead of the time at which it was published.

If this is true, is there a way to force a rosbag to instead encode messages with the timestamp which were published with them?

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