test_gsl AKA covar

0. First things

Ensure that gsl is installed: sudo apt-get install libgsl2 libgsl-dev libgsl-dbg gsl-bin

1. Getting the package

Do the following to add to the src of your ROS workspace (i.e. catkin_ws if you kept the dirname from ROS tutorial), almost as you would any other package - we're going to give this repo's dirname "covar" instead of "test_gsl".

• cd path/to/catkin_ws/src; git clone https://github.com/ntwong0/test_gsl.git -b ROSify covar

2. Installation

catkin_make as usual:

• cd path/to/catkin_ws; catkin_make

Please note RE: the loam_velodyne package

• Although covar is a general std_msgs/Odometry republisher, it was built with loam_velodyne in mind.
  • Note that its build instructions specifies the -DCMAKE_BUILD_TYPE=Release flag. Please obey this, otherwise your loam_velodyne node will not work!
• Note that loam_velodyne uses the XZ plane rather than the XY plane, so you'll to translate the axes. The covar launch file loam_velodyne_with_covar.launch creates the two static transforms you need, but if you want to run them yourself:
  1. Tie /camera_init to /world: rosrun tf2_ros static_transform_publisher 0 0 0 0 0 1.5708 /world /camera_init
  2. Tie /map to /world (assuming your map tf is /map): rosrun tf2_ros static_transform_publisher 0 0 0 0 0 0 /world /map

3. Running

As always, be sure to source the appropriate setup.bash file, i.e.

• cd path/to/catkin_ws; source devel/setup.bash

You can run covar independently via rosrun:

• rosrun covar covar_node

If you're using covar with loam_velodyne, you can run the following command:

• roslaunch covar loam_velodyne_with_covar.launch

4. Service calls - this is why you "bought" it

Generate the covariance matrix with the following:

• For pose only, 100 samples
  • rosservice call /gen_pose_covar 100
• For twist only, 100 samples
  • rosservice call /gen_twist_covar 100
• For pose and twist, 100 samples pose and 200 samples twist
  • rosservice call /gen_both_covar 100 200

5. Versioning

• 0.1.0 (published 2018-11-01 via 6c56a64)
  • Republishes an input std_msgs/Odometry topic
    • Excludes the covariance of the input's messages
  • Generates covariances for pose and/or twist from the input std_msgs/Odometry topic
  • Accepts rosservice calls to perform covariance generation
• 0.2.0 (ETA 2018-11-30)
  • Provide .launch file for ease of execution via roslaunch
  • rosparam-ify input and output topic
  • rosparam-ify covariance matrices for pose and twist
  • rosservice call for changing covariance matrices on-the-fly
• 0.3.0 (ETA 2018-12-07)
  • Also generate covariance for accelerometer data

999. Dummy compilation note:

To compile, do the following:

g++ -std=c++11 src/file.cpp -lgsl -lgslcblas -Iinclude

Header files of the gsl library are located at /usr/include/gsl