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2021-08-01 07:25:21 -0500 commented answer Can't build with roslaunch as a dependency

As far as I can tell roslaunch is not a build_depend, it's just called with find_package in CMake. I've inherited a repo

2021-08-01 07:25:09 -0500 commented answer Can't build with roslaunch as a dependency

As far as I can tell roslaunch is not a build_depend, it's just called with find_package in CMake. I've inherited a repo

2021-08-01 07:23:23 -0500 commented answer Can't build with roslaunch as a dependency

Love it, super simple fix, thanks! sudo apt remove python3-roslaunch and sudo apt install ros-noetic-roslaunch did indee

2021-08-01 07:14:59 -0500 marked best answer Can't build with roslaunch as a dependency

I've been given a repo with roslaunch as a dependency in the CMake files, and it fails to build like so:

-- Could NOT find roslaunch (missing: roslaunch_DIR)
-- Could not find the required component 'roslaunch'. The following CMake error indicates that you either need to install the package with the same name or change your environment so that it can be found.
CMake Error at /opt/ros/noetic/share/catkin/cmake/catkinConfig.cmake:83 (find_package):
  Could not find a package configuration file provided by "roslaunch" with
  any of the following names:


So I tried creating a fresh catkin package to see if I can recreate the issue. Even with the fresh catkin package roslaunch is causing catkin_make issues, I'll walk through them here.

Just to confirm at the beginning, roslaunch is installed. The first time I saw the build error below I installed it with sudo apt install python3-roslaunch. If that method of install is the problem that'd be an easy fix, but I think it's okay.

eric@laptop:~/tutorials/catkin_ws$ roslaunch -h
Usage: roslaunch [options] [package] <filename> [arg_name:=value...]
       roslaunch [options] <filename> [<filename>...] [arg_name:=value...]

If <filename> is a single dash ('-'), launch XML is read from standard input.

Okay, how to create the issue. I started from the basic ROS build-a-package tutorial like so:

eric@laptop:~/tutorials$ source /opt/ros/noetic/setup.bash
eric@laptop:~/tutorials$ printenv | grep ROS
eric@laptop:~/tutorials$ mkdir -p catkin_ws/src/
eric@laptop:~/tutorials$ cd catkin_ws/
eric@laptop:~/tutorials/catkin_ws$ ls
eric@laptop:~/tutorials/catkin_ws$ catkin_make
Base path: /home/eric/tutorials/catkin_ws
#### Running command: "make -j8 -l8" in "/home/eric/tutorials/catkin_ws/build"
eric@laptop:~/tutorials/catkin_ws$ ls
build  devel  src
eric@laptop:~/tutorials/catkin_ws$ source devel/setup.bash
eric@laptop:~/tutorials/catkin_ws$ cd src/

eric@laptop:~/tutorials/catkin_ws/src$ catkin_create_pkg figuring_out_roslaunch_issue roscpp rospy roslaunch std_msgs
Created file figuring_out_roslaunch_issue/package.xml
Created file figuring_out_roslaunch_issue/CMakeLists.txt
Created folder figuring_out_roslaunch_issue/include/figuring_out_roslaunch_issue
Created folder figuring_out_roslaunch_issue/src
Successfully created files in /home/eric/tutorials/catkin_ws/src/figuring_out_roslaunch_issue. Please adjust the values in package.xml.

eric@laptop:~/tutorials/catkin_ws/src$ cd ..
eric@laptop:~/tutorials/catkin_ws$ catkin_make
Base path: /home/eric/tutorials/catkin_ws
Source space: /home/eric/tutorials/catkin_ws/src
Build space: /home/eric/tutorials/catkin_ws/build
Devel space: /home/eric/tutorials/catkin_ws/devel
Install space: /home/eric/tutorials/catkin_ws/install
#### Running command: "cmake /home/eric/tutorials/catkin_ws/src -DCATKIN_DEVEL_PREFIX=/home/eric/tutorials/catkin_ws/devel -DCMAKE_INSTALL_PREFIX=/home/eric/tutorials/catkin_ws/install -G Unix Makefiles" in "/home/eric/tutorials/catkin_ws/build"
-- Using CATKIN_DEVEL_PREFIX: /home/eric/tutorials/catkin_ws/devel
-- Using CMAKE_PREFIX_PATH: /home/eric/tutorials/catkin_ws/devel;/opt/ros/noetic
-- This workspace overlays: /home/eric/tutorials/catkin_ws/devel;/opt/ros/noetic
-- Found PythonInterp: /usr/bin/python3 (found suitable version "3.8.10", minimum required is "3") 
-- Using PYTHON_EXECUTABLE: /usr/bin/python3
-- Using Debian Python package layout
-- Using empy: /usr/lib ...
2021-07-31 23:18:22 -0500 asked a question Can't build with roslaunch as a dependency

Can't build with roslaunch as a dependency I've been given a repo with roslaunch as a dependency in the CMake files, and

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2017-07-02 22:50:17 -0500 marked best answer Mavros topics not publishing?


I've been trying to connect to a Pixhawk quadcopter using the mavros library ( ) and I had some issues. We are using a pixhawk and a 3DR Iris quadcopter, and we launch the mavros code with

roslaunch mavros apm2_radio.launch

The code launches with no errors are we see a long list of topics being displayed:


The good news is that the /mavros/state, /diagnostics, and /mavros/radio_status seem to be publishing correctly

$:rostopic echo /mavros/state
      seq: 100
        secs: 1411583514
        nsecs: 793784329
      frame_id: ''
    armed: False
    guided: False
    mode: ALT_HOLD

The bad news is that every other topic is empty. No GPS data, no battery data, no RC data, etc. Has anyone else run this code and knows how to get this data to publish?

The closest thing online I found is this online book:

The problem is, they experienced the same problem but gave no reason/fix for it.


EDIT: Adding information On a fresh install of Ubuntu 14.04 and a newly installed mavros

sudo apt-get install mavros

I tried to get sensor data from a 3DR Iris Pixhawk. As per @vooon 's suggestion, I used rqt_logger_level to view the mavros.ros.mavconn debug messages.

# Changed the default fcu_url to ttyUSB0 instead of ttyACM0, because that's the port my 3DR modem was on.
<arg name="fcu_url" default="/dev/ttyUSB0:57600" />

Launched the file using px4.launch, enabled mavconn Debug messages, and watched the message ID's that showed up.

  1. First, during the section where you get the heartbeat, there were a mixture of 0, 166, and 109 messages.
  2. Then message ID 253 was published three times in a row, in conjunction with FCU lines for ArduCopter V3.1.2, PX4 and PX4v2:

    [DEBUG] [1411862177.961715937]: serial0:recv: Message-Id: 253 [51 bytes] Sys-Id: 1 Comp-Id: 1 [ INFO] [1411862177.961821314]: FCU: ArduCopter V3.1.2 (e2ed3dd1)

  3. After that, during bootup, there is a fast stream of 22 IDs split up by 0, 166, and 109

  4. At the end of a long stream of 22's it gets 43, 44, 40, 39, and 47 in quick succession:

    [DEBUG] [1411862299.848786274]: serial0:send: Message-Id: 43 [2 bytes] [DEBUG] [1411862299.929775171]: serial0:recv: Message-Id: 44 [4 bytes] Sys-Id: 1 Comp-Id: 1 [DEBUG] [1411862299.929917816]: serial0:send: Message-Id: 40 [4 bytes] [DEBUG] [1411862300.143771523]: serial0:recv: Message-Id: 39 [37 bytes] Sys-Id: 1 Comp-Id: 1 [ INFO] [1411862300.143899206]: WP: item #0 GAA WAYPOINT CUR params: 0, 0, 0, 0 x: 42.2936 y: -71.2638 z: 0 [DEBUG] [1411862300.143942143]: serial0:send: Message-Id: 47 [3 bytes] [ INFO] [1411862300.143995581]: WP: mission received [ WARN] [1411862300.673739713]: PR: request param #133 timeout, retries left 2, and ...

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2016-05-04 13:48:48 -0500 asked a question UR10 control with ROS Industrial failing with firmware 3.2.18744


I've been using the ROS universal robotics code on a UR5 arm for a while, and tried using the code on a more recently obtained UR10. The code in ur_driver started dying because the packet being unpacked is an expected size (46 instead of the packet sizes that are known, 29 and 38).

Is anyone else running into this issue? Are the packets a new length because of the different firmware versions? Or are the packets a new length because I moved from UR5 to UR10


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2015-01-22 17:58:00 -0500 commented answer OpenGL error when run rviz

Hm. In that case I don't know how to fix the problem. I'll try to figure out which drivers I'm using. Thanks.

2015-01-22 14:57:43 -0500 commented answer OpenGL error when run rviz

Hi, I'm running into the exact same problem as the original post (my OpenGL version is also 1.4) but exporting LIBGL_ALWAYS_SOFTWARE=1 does not fix the problem. I'll run the two lines you mention and the exact same error will occur. Is there anything else to test for/try as a fix?

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2014-12-30 13:44:43 -0500 commented answer How does Mavros RC override work?

I'm away from the quadcopter for a couple weeks, but I'll look into it when I get back, thanks!

2014-12-30 12:56:40 -0500 commented question How does Mavros RC override work?

Unfortunately not, I'm not sure what's going on with the RC topics. I've been working on other stuff in the meantime.

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2014-11-09 22:54:18 -0500 asked a question How does Mavros RC override work?


I've been trying to work with the mavros, but the wiki doesn't have a lot of detail about it. I'm using an Iris and connecting with roslaunch mavros apm2_radio.launch.

First I'm setting SYSID_MYGCS to 1, as specified at the bottom of this github issue. Then I'm publishing messages on the command line

$ rosrun mavros mavparam set SYSIS_MYGCS 1
$ rostopic pub -1 /mavros/rc/override mavros/OverrideRCIn '[1500, 1500, 1500, 1500, 1325, 1560, 2000, 1500]'

I'm testing RC by leaving the quadcopter in an unarmed state, connecting a gimbal to RC Channel 6 using APM Mission Planner, then publishing various values on Channel 6 (1560 in the example code) and trying to get the gimbal to move. What happens now is that

  1. When the quadcopter is first powered I have control of the gimbal using our RC controller, channel 6
  2. After setting the SYSID_MYGCS value I still have control with the RC controller
  3. Publishing a mavros/rc/override message with a small deviation in the Channel 6 value does not change the gimbal position, but it does make it so that the RC controller can no longer affect the gimbal position
  4. Publishing messages with a variety of Channel 6 values has no effect, except when there is a large change of >150 in the Channel 6 measurement. This makes the gimbal travel fully in one direction and stay stuck there until you send a largely different Channel 6 value that makes the gimbal rail in the other direction.

I feel like I just don't understand what mavros/rc/override is sending to the quadcopter. The gimbal is perfectly controllable using the RC controller before we publish anything to mavros/rc/override, so we know the gimbal is commandable with Channel 6.

I apologize if this is a drone-discuss (or other quadcopter forum) question, not a mavros question, but I don't have a good enough understanding of what mavros is calling under the surface in order to usefully search the drone-discuss forums. If someone has a link to useful non-ROS information I'd welcome it...

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2014-10-12 16:00:11 -0500 commented answer Mavros not arming quadcopter?

Others can see the related drone-discuss question here:!sea...

2014-10-11 18:44:48 -0500 commented answer Mavros topics not publishing?

Sometimes this error will come up again and running APM Mission Planner, connecting, and disconnecting will help solve the issue.

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2014-10-08 10:02:12 -0500 commented answer Mavros topics not publishing?

Hi Christopher, I opened a new question here:

It might be cleanest if you move your query there, but probably not a big deal

2014-10-08 10:01:31 -0500 asked a question Mavros not arming quadcopter?


I've been trying to use mavros ( ) to fly a 3DR Iris quadcopter that has a Pixhawk on it, but we're having trouble arming the system.

Run through of the scenario:

  1. We're inside, plug the battery in for the quadcopter, and the quad goes to flashing blue. This stands for "Autopilot ready but no GPS lock". We can arm the quadcopter with the RC controller at this point.
  2. We plug in the radio modem and run 'roslaunch mavros apm2_planner.launch'. At this point we are connected to the quadcopter. When we rostopic echo the /mavros/battery and /mavros/imu/raw_data topics (among others) we get good data. We can pull and push missions.
  3. We put the RC controller in AUTO mode
  4. We run 'rosservice call /mavros/cmd/arming true' in a new terminal, it returns

    success: false

    result: 3

Does anyone have any ideas? Do we need to be outside with GPS fix? Are there any flags that need to be satisfied in the code before it will allow arming?