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<< SOLVED>>>

I'm new to this, so this is only for reference, I am by no means a professional. After some long hours, I have made the arm move!! I thought I would show the files I used to make it work since it is not so simple for some. If you have already downloaded the arbotix package, and used the 'arbotix_terminal' to find all of your dynamixel ax-12 servos (I will assume you have already done this after installing the arbotix package). Also, I will assume that you have loaded ROS onto your arbotix controller with the Arduino IDE as described here. I will now describe the files I needed to accomplish this. Good luck!!

Create a new package

$ cd ~/catkin_ws/src
$ catkin_create_package arbotix_ros std_msgs rospy roscpp
$ cd arbotix_ros

In the src folder, update your package.xml to look like this...

<?xml version="1.0"?>
<package>
  <name>ros_arbx</name>
  <version>0.0.0</version>
  <description>The ros_arbx package</description>

  <maintainer email="ubuntu@todo.todo">ubuntu</maintainer>

  <license>TODO</license>

  <buildtool_depend>catkin</buildtool_depend>
  <build_depend>roscpp</build_depend>
  <build_depend>rospy</build_depend>
  <build_depend>std_msgs</build_depend>
  <run_depend>roscpp</run_depend>
  <run_depend>rospy</run_depend>
  <run_depend>std_msgs</run_depend>


  <export>

  </export>
</package>

Then make your CMakeLists.txt look like this...

cmake_minimum_required(VERSION 2.8.3)
project(ros_arbx)

## Find catkin macros and libraries
## if COMPONENTS list like find_package(catkin REQUIRED COMPONENTS xyz)
## is used, also find other catkin packages
find_package(catkin REQUIRED COMPONENTS
  roscpp
  rospy
  std_msgs
)

## System dependencies are found with CMake's conventions
# find_package(Boost REQUIRED COMPONENTS system)


## Uncomment this if the package has a setup.py. This macro ensures
## modules and global scripts declared therein get installed
## See http://ros.org/doc/api/catkin/html/user_guide/setup_dot_py.html
# catkin_python_setup()

################################################
## Declare ROS messages, services and actions ##
################################################

## To declare and build messages, services or actions from within this
## package, follow these steps:
## * Let MSG_DEP_SET be the set of packages whose message types you use in
##   your messages/services/actions (e.g. std_msgs, actionlib_msgs, ...).
## * In the file package.xml:
##   * add a build_depend tag for "message_generation"
##   * add a build_depend and a run_depend tag for each package in MSG_DEP_SET
##   * If MSG_DEP_SET isn't empty the following dependency has been pulled in
##     but can be declared for certainty nonetheless:
##     * add a run_depend tag for "message_runtime"
## * In this file (CMakeLists.txt):
##   * add "message_generation" and every package in MSG_DEP_SET to
##     find_package(catkin REQUIRED COMPONENTS ...)
##   * add "message_runtime" and every package in MSG_DEP_SET to
##     catkin_package(CATKIN_DEPENDS ...)
##   * uncomment the add_*_files sections below as needed
##     and list every .msg/.srv/.action file to be processed
##   * uncomment the generate_messages entry below
##   * add every package in MSG_DEP_SET to generate_messages(DEPENDENCIES ...)

## Generate messages in the 'msg' folder
# add_message_files(
#   FILES
#   Message1.msg
#   Message2.msg
# )

## Generate services in the 'srv' folder
# add_service_files(
#   FILES
#   Service1.srv
#   Service2.srv
# )

## Generate actions in the 'action' folder
# add_action_files(
#   FILES
#   Action1.action
#   Action2.action
# )

## Generate added messages and services with any dependencies listed here
# generate_messages(
#   DEPENDENCIES
#   std_msgs
# )

################################################
## Declare ROS dynamic reconfigure parameters ##
################################################

## To declare and build dynamic reconfigure parameters within this
## package, follow these steps:
## * In the file package.xml:
##   * add a build_depend and a run_depend tag for "dynamic_reconfigure"
## * In this file (CMakeLists.txt):
##   * add "dynamic_reconfigure" to
##     find_package(catkin REQUIRED COMPONENTS ...)
##   * uncomment the "generate_dynamic_reconfigure_options" section below
##     and list every .cfg file to be processed

## Generate dynamic reconfigure parameters in the 'cfg' folder
# generate_dynamic_reconfigure_options(
#   cfg/DynReconf1.cfg
#   cfg/DynReconf2.cfg
# )

###################################
## catkin specific configuration ##
###################################
## The catkin_package macro generates cmake config files for your package
## Declare things to be passed to dependent projects
## INCLUDE_DIRS: uncomment this if you package contains header files
## LIBRARIES: libraries you create in this project that dependent projects also need
## CATKIN_DEPENDS: catkin_packages dependent projects also need
## DEPENDS: system dependencies of this project that dependent projects also need
catkin_package(
#  INCLUDE_DIRS include
#  LIBRARIES ros_arbx
#  CATKIN_DEPENDS roscpp rospy std_msgs
#  DEPENDS system_lib
)

###########
## Build ##
###########

## Specify additional locations of header files
## Your package locations should be listed before other locations
# include_directories(include)
include_directories(
  ${catkin_INCLUDE_DIRS}
)

## Declare a C++ library
# add_library(ros_arbx
#   src/${PROJECT_NAME}/ros_arbx.cpp
# )

## Add cmake target dependencies of the library
## as an example, code may need to be generated before libraries
## either from message generation or dynamic reconfigure
# add_dependencies(ros_arbx ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})

## Declare a C++ executable
# add_executable(ros_arbx_node src/ros_arbx_node.cpp)

## Add cmake target dependencies of the executable
## same as for the library above
# add_dependencies(ros_arbx_node ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})

## Specify libraries to link a library or executable target against
# target_link_libraries(ros_arbx_node
#   ${catkin_LIBRARIES}
# )

#############
## Install ##
#############

# all install targets should use catkin DESTINATION variables
# See http://ros.org/doc/api/catkin/html/adv_user_guide/variables.html

## Mark executable scripts (Python etc.) for installation
## in contrast to setup.py, you can choose the destination
# install(PROGRAMS
#   scripts/my_python_script
#   DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
# )

## Mark executables and/or libraries for installation
# install(TARGETS ros_arbx ros_arbx_node
#   ARCHIVE DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
#   LIBRARY DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
#   RUNTIME DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
# )

## Mark cpp header files for installation
# install(DIRECTORY include/${PROJECT_NAME}/
#   DESTINATION ${CATKIN_PACKAGE_INCLUDE_DESTINATION}
#   FILES_MATCHING PATTERN "*.h"
#   PATTERN ".svn" EXCLUDE
# )

## Mark other files for installation (e.g. launch and bag files, etc.)
# install(FILES
#   # myfile1
#   # myfile2
#   DESTINATION ${CATKIN_PACKAGE_SHARE_DESTINATION}
# )

#############
## Testing ##
#############

## Add gtest based cpp test target and link libraries
# catkin_add_gtest(${PROJECT_NAME}-test test/test_ros_arbx.cpp)
# if(TARGET ${PROJECT_NAME}-test)
#   target_link_libraries(${PROJECT_NAME}-test ${PROJECT_NAME})
# endif()

## Add folders to be run by python nosetests
# catkin_add_nosetests(test)

Create a dynamiel_params.yaml file that looks like this...

port: /dev/ttyUSB0
baud: 115200
rate: 70
read_rate: 70
write_rate: 70

joints: {
    head_pan_joint: {id: 1, neutral: 512, max_speed: 100, min_angle: 2.0, max_angle: 2.0, invert: true},
    head_tilt_joint: {id: 2, neutral: 512, max_speed: 100, max_angle: 612, min_angle: 412},
    head_topple_joint: {id: 3, neutral: 512, max_speed: 100, max_angle: 712, min_angle: 312}
}

controllers: {
  head_controller: {type: follow_controller, joints: [head_pan_joint, head_tilt_joint, head_topple_joint], action_name: head_controller/follow_joint_trajectory },
  base_controller: {type: diff_controller, base_width: 0.140, ticks_meter: 26145 }
}

Create an arbotix.launch file and make it look like this...

<launch>
  <node name="arbotix" pkg="arbotix_python" type="arbotix_driver" output="screen">
    <rosparam file="$(find YOUR_PACKAGES_NAME)/dynamixel_params.yaml" command="load" />
  </node>
</launch>

Then to control the arm. Create a mover.py file that looks like this...

#!/usr/bin/env python

import rospy
from std_msgs.msg import Float64


def talker():

    # Set up for 3 joint arm (Anthropomorphic)
    pan = rospy.Publisher('/head_pan_joint/command', Float64, queue_size=10)
    tilt = rospy.Publisher('/head_tilt_joint/command', Float64, queue_size=10)
    topple = rospy.Publisher('/head_topple_joint/command', Float64, queue_size=10)

    # Make this a node in Ros
    rospy.init_node('mover')

    # The rate at which the messages are sent
    rate = rospy.Rate(70)  # 10hz

    # This will just move it to a position
    # A loop is not needed.
    while not rospy.is_shutdown():

        # Create the end position (in radians)
    pan_pos = -1.0
        tilt_pos = 0.5
        topple_pos = -1.0

        # Log the information to /rosout
    rospy.loginfo(pan_pos)
        rospy.loginfo(tilt_pos)
        rospy.loginfo(topple_pos)

    # Finally, publish to a node
    pan.publish(pan_pos)
        tilt.publish(tilt_pos)
        topple.publish(topple_pos)

    rate.sleep()

if __name__ == '__main__':
    try:
        talker()
    except rospy.ROSInterruptException:
        pass

catkin_make the file then source it...

$ cd ~/catkin_ws
$ catkin_make
$ source devel/setup.bash

Finally, while running roscore and having everything set connected, powered, and running, type...

$ roslaunch arbotix_ros arbotix.launch

In another terminal, run...

$ cd src/arbotix_ros
$ python move.py

Hope this works for you, too!!