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2019-06-25 18:34:27 -0600 answered a question Flycapture software for point grey camera

I downloaded a tgz file from Flir site, and did "sneaker net" to transfer via USB memory stick. Just unzip the file, an

2019-06-25 17:37:28 -0600 edited answer AMCL and gmapping combination problem

Gmapping (or Cartographer) is used when you do NOT have an existing map and you need to do SLAM - Simultaneous Localizat

2019-06-25 17:36:00 -0600 answered a question AMCL and gmapping combination problem

Gmapping (or Cartographer) is used when you do not have an existing map to do SLAM - Simultaneous Localization and Mappi

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2017-08-14 11:45:16 -0600 answered a question FlexBE does but does not connect

This was asked and answered on with no follow up from use

2017-08-14 11:37:30 -0600 commented question FlexBE does but does not connect

We are following at

2017-06-26 14:04:02 -0600 commented question Use pycharm for Flexbe

Duplicate discussion from: You might want to edit this

2017-04-20 14:35:25 -0600 marked best answer ros-jade-desktop-full not setting up ros or gazebo setup files properly

Normally, after an install of ros-jade-desktop-full on Ubuntu 14.04.3 LTS (trusty) 64-bit, the gazebo 5.0 package is setup to run properly.

I tried to set up a new computer this afternoon, and it is giving me an error because there is no /usr/share/gazebo library.

I know this was working a couple of weeks ago. Has there been a change to debs that busted this?

Attached is screen shot of result: image description

This after apt-get removing prior attempts, apt-get updating/upgrading, and rebooting. I started install of ros-jade-desktop-full, and redirected to file. The install seems to complete without error, but I have no /usr/share/gazebo folder and no setup files in the /opt/ros/jade folder

2017-03-27 16:37:23 -0600 answered a question Are JointPositionControllers supposed to wrap angles on continuous joints?

Can you change URDF to use "Revolute" joint with arbitrarily large joint limits?

Continuous joints are supposed to be like wheels. Revolute joints can spin a limited number of times, but I think they preserve their internal angles.

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2017-02-20 10:04:32 -0600 commented question Ros running on 2 machines, one master, subscriber not getting any message

If you are using HOSTNAME, you need to have consistent /etc/hosts files on both machines

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2016-12-20 11:18:04 -0600 commented answer multiple robots in ROS kinetic with Gazebo 7

That worked for me. I would be interested to hear from OSRF folks about their planned roadmap for handling this with tf_prefix supposedly being deprecated.

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2016-12-19 23:18:34 -0600 asked a question multiple robots in ROS kinetic with Gazebo 7

Can anyone point me to a good example of using a single URDF and instantiating multiple robots in Gazebo, and also having a consistent transform (tf2) tree?

There are several instances of questions on this forum that are old, and all refer to setting the tf_prefix, which is deprecated. (c.f. )

I have tried several variations of changes to name space, that will get me the robots spawning correctly in Gazebo, and topics named correctly, but the tf tree is not consistent with I view the robot model in RVIz.

I am specifically interested in the turtlebot models, but any consistent set of URDF and launch files should be sufficient to point me in the right direction with the new setup.

Or if someone can point me to an up to date tutorial I would appreciate it.

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2016-07-07 11:34:26 -0600 commented question How to build two packages at the same time

Is uvc_cam listed as a dependency in the ar_sys CMakeLists.txt file?

Unless it is explicitly listed as dependency, then CMake won't know to build it first.

2016-07-07 11:31:46 -0600 answered a question how to get Twist.h file for joystick controled turtlesim?

You need to add a dependency for geometry_msgs to your package and CMakeLists.txt.

See the message tutorials for how to do that.

2016-07-07 11:30:03 -0600 answered a question How can i send markers to specified position along with point cloud, inside rviz ?

You need to publish a specific marker message. You code needs to define the type and location of the markers, and publish them to a topic.

2016-07-07 11:27:21 -0600 commented answer Is there a simple way to find ROS headers in CMake without catkin?

Gah! Thanks. I thought the example I was following made the tags all upper case.

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2016-07-06 19:03:09 -0600 asked a question Is there a simple way to find ROS headers in CMake without catkin?

I am building an external library that will be linked in as part of a ros package, but is built outside of Catkin.

I'd like to use some of the ROS messages (e.g. ROS_INFO, ROS_DEBUG) inside this library for debugging.

I have manually modified the CMake to include_directories( /opt/ros/kinetic/include/) and the code works as I want.

I'd like to do something like:

find_package( roscpp )

Unfortunately, CMake can't find roscpp without all of the catkin magic.
I don't want to find_package(catkin) as it messes with the normal CMake build setup for the library.

One hack I can think of is to check the ROS_ROOT environment variable, and if it exists, make the include relative to that. But that is a hack that I'd prefer to avoid.

Is there a clean minimal setup that can discover the ROS include directory with pure CMake?

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2016-07-06 18:46:30 -0600 commented answer Best practice for incorporating catkin into larger CMake project?

Unfortunately it has been a while, and I not longer have access to the "hack" setup

2016-07-06 18:42:28 -0600 commented answer Suggest good example of multi-threading with ROS?

Unfortunately, our main controller contained proprietary data and we could not open source it.

2016-04-19 06:00:22 -0600 marked best answer Suggest good example of multi-threading with ROS?

Can some someone point me to a good example of multi-threading using ROS?

I would like to move calculations outside the main ROS callbackQueue, and then publish a topic after the calculations are done.

Searching wiki and answers.ros 53055, I see suggestions to do this, and to use boost::thread, but it's not clear how best to tie the results back to publishing an advertised topic.

Should I create a separate node handle, and advertise from within the worker thread? Or, is publish/node handle thread safe so that I can call publish from within worker thread using a node handle and topic initialized/advertised in the main thread?

2016-04-04 07:53:20 -0600 marked best answer cv2 (2.4.8) missing DIST_L2 for distanceTransform?

I'm trying to implement a image segmentation node. If I following the image segementation example code

 dist_transform = cv2.distanceTransform(opening, cv2.DIST_L2, 5)

I get the following error:

AttributeError: 'module' object has no attribute 'DIST_L2'

Checking the __dict_ there is not a DIST_L2. I tried substituting NORM_L2, but that did not give the expected result.

The "import cv2" gives me version 2.4.8 (as installed by ROS Jade on Ubuntu 14.04)

Has anyone seen this issue?

Is it possible to use OpenCV 3 in python, or is that only for C++?

2016-04-04 07:53:18 -0600 commented answer cv2 (2.4.8) missing DIST_L2 for distanceTransform?

Supposedly OpenCV 3 is installed with Jade. The directions for using with C++ seem straightforward with CMake, but I'm not sure about Python.

Does OpenCV 3 work with Python in the Jade installation?