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Setting Up Dynamic Reconfigure for a Node

Description: Setting Up Dynamic Reconfigure for a Node

Keywords: dynamic_reconfigure configure cpp

Tutorial Level: INTERMEDIATE

A simple example of a dynamically reconfigurable node can be found under dynamic_reconfigure/test

Setting Up Dynamic Reconfigure for a Node

This example shows how to setup a dynamic reconfigure node to reconfigure variables in the ROS message driver_base/SensorLevels.h. Suppose you are adding the dynamic reconfigure server node to your package which we'll refer to as your_package from now on.

  1. Make your package depend on dynamic_reconfigure by adding this line to your manifest.xml,

      <depend package="dynamic_reconfigure" />
  2. or if your ROS distribution is Groovy or higher use this:

The example below will also need

  •   <depend package="driver_base" />
  • or if your ROS distribution is Groovy or higher use this:
  • Create a configuration file, saved it as your_package/cfg/MyStuff.cfg:

    # Forearm camera configuration
    import roslib; roslib.load_manifest(PACKAGE)
    from math import pi
    from driver_base.msg import SensorLevels
    from dynamic_reconfigure.parameter_generator import *
    gen = ParameterGenerator()
    angles = gen.add_group("Angles")
    #       Name                    Type      Reconfiguration level
    #       Description
    #       Default  Min  Max
    angles.add("min_ang",           double_t, SensorLevels.RECONFIGURE_STOP,
               "The angle of the first range measurement. The unit depends on ~ang_radians.",
               -pi/2,-pi, pi)
    angles.add("max_ang",           double_t, SensorLevels.RECONFIGURE_STOP,
               "The angle of the first range measurement. The unit depends on ~ang_radians.",
                pi/2, -pi, pi)
    gen.add("intensity",            bool_t,   SensorLevels.RECONFIGURE_STOP,
            "Whether or not the hokuyo returns intensity values.",
    gen.add("cluster",              int_t,    SensorLevels.RECONFIGURE_STOP,
            "The number of adjacent range measurements to cluster into a single reading",
             1, 0, 99)
    gen.add("skip",                 int_t,    SensorLevels.RECONFIGURE_STOP,
            "The number of scans to skip between each measured scan",
             0, 0,  9)
    gen.add("port",                 str_t,    SensorLevels.RECONFIGURE_CLOSE,
            "The serial port where the hokuyo device can be found",
    gen.add("calibrate_time",       bool_t,   SensorLevels.RECONFIGURE_CLOSE,
            "Whether the node should calibrate the hokuyo's time offset",
    gen.add("frame_id",             str_t,    SensorLevels.RECONFIGURE_RUNNING,
            "The frame in which laser scans will be returned",
    gen.add("time_offset",          double_t, SensorLevels.RECONFIGURE_RUNNING,
            "An offet to add to the timestamp before publication of a scan",
             0, -0.25, 0.25)
    gen.add("allow_unsafe_settings",bool_t,   SensorLevels.RECONFIGURE_CLOSE,
            "Turn this on if you wish to use the UTM-30LX with an unsafe angular range. Turning this option on may cause occasional crashes or bad data. This option is a tempory workaround that will hopefully be removed in an upcoming driver version.",
    exit(gen.generate(PACKAGE, "dynamic_reconfigure_node", "MyStuff"))


  • Make the .cfg file executable

    chmod a+x your_package/cfg/MyStuff.cfg
  • Create a ROS node that processes callbacks, for example, save the following file as your_package/src/dynamic_reconfigure_node.cpp:

       1 #include <dynamic_reconfigure/server.h>
       2 #include <your_package/MyStuffConfig.h>
       4 void callback(your_package::MyStuffConfig &config, uint32_t level)
       5 {
       6   ROS_INFO("Reconfigure request : %f %f %i %i %i %s %i %s %f %i",
       7            config.groups.angles.min_ang,
       8            config.groups.angles.max_ang,
       9            (int)config.intensity,
      10            config.cluster,
      11            config.skip,
      12            config.port.c_str(),
      13            (int)config.calibrate_time,
      14            config.frame_id.c_str(),
      15            config.time_offset,
      16            (int)config.allow_unsafe_settings);
      18   // do nothing for now
      19 }
      21 int main(int argc, char **argv)
      22 {
      23   ros::init(argc, argv, "dynamic_reconfigure_node");
      24   dynamic_reconfigure::Server<your_package::MyStuffConfig> srv;
      25   dynamic_reconfigure::Server<your_package::MyStuffConfig>::CallbackType f;
      26   f = boost::bind(&callback, _1, _2);
      27   srv.setCallback(f);
      28   ROS_INFO("Starting to spin...");
      29   ros::spin();
      30   return 0;
      31 }
  • Update your CMakeLists.txt to compile above by adding these lines

    # add dynamic reconfigure api
    rosbuild_add_executable(dynamic_reconfigure_node src/dynamic_reconfigure_node.cpp)
  • or if your ROS distribution is Groovy or higher use this:
     . find_package(catkin REQUIRED COMPONENTS dynamic_reconfigure ) 
     . generate_dynamic_reconfigure_options( cfg/MyStuff.cfg)  
     . include_directories(${dynamic_reconfigure_PACKAGE_PATH}/cmake/cfgbuild.cmake) 
     . add_executable(dynamic_reconfigure_node src/dynamic_reconfigure_node.cpp)
     . add_dependencies(dynamic_reconfigure_node ${PROJECT_NAME}_gencfg)
     . target_link_libraries(dynamic_reconfigure_node ${catkin_LIBRARIES})
  • rosmake your package and launch the node.
    rosrun your_package dynamic_reconfigure_node

  1. taken directly from forearm camera configuration. (1)

Wiki: dynamic_reconfigure/Tutorials/SettingUpDynamicReconfigureForANode (last edited 2015-05-08 09:04:06 by winstonyao)