rosarnl

The rosarnl package contains a ROS node called rosarnl_node which provides a ROS interface to basic ARNL features.

rosarnl requires ARNL and ArnlBase 1.9.2 or later to be installed. The packages from Adept MobileRobots must be installed separately, they cannot currently be downloaded rosdep/catkin. Download from http://robots.mobilerobots.com/wiki/ARNL. "Prerelease" testing packages for 1.9.2 can be found at http://robots.mobilerobots.com/ARNL/download/prerelease and http://robots.mobilerobots.com/BaseArnl/download/prerelease.

To build, check out the repository in the src subdirectory of your ROS (catkin) workspace. ros-arnl depends on several ROS packages including nav_msgs, geometry_msgs, tf, move_base_msgs, actionlib, and actionlib_msgs. To install these automatically, run rosdep update, then run rosdep install rosarnl. (You may need to import the ROS development environment to your shell first by running . devel/setup.bash from your catkin workspace directory.) Run catkin_make --pkg rosarnl from the workspace directory to build.

To run rosarnl_node, use rosrun: rosrun rosarnl rosarnl_node. It will connect to the robot and begin running.

In addition, ARNL ArNetworking services are provided, so ARNL can be accessed and configured via MobileEyes or other ArNetworking clients simultaneously with the ROS interface. Use MobileEyes to perform scanning for map generation, configure ARNL, and more easily do some tasks such as teleoperation and initial manual localization. Use Mapper3 to process the scan and upload the map to ARNL. See the MobileRobots ARNL/Navigation guides, robot manuals, ARNL reference API documentation, and documentation at http://robots.mobilerobots.com for more details on how to use ARNL.

rosarnl_node is self-contained. It does not require any other ROS nodes to be running. It will connect directly to the robot and laser rangefinder(s), according to ARNL's robot parameters.

This is intended for simple operation of ARNL navigation, and as a base for further features to be added.

Some ROS navstack interface compatibiliy is provided (see below). Some tasks will need to be performed by MobileEyes and Mapper3 instead.

See LICENSE.txt for the license terms for this code. Note that it is not BSD or GPL, and has additional restrictions on use. ARNL and ArnlBase are provided under their own MobileRobots Individual Software License, and you must have purchased ARNL license(s) with your robot system in order to use the ARNL and ArnlBase libraries.

Topic and service interface

Autonomous Navigation (path planning and localization):

The rosarnl node provides a subset of the standard ROS navigation topic interface (See http://wiki.ros.org/move_base and other documentation). Note however that by default the topics are prefixed with /ronarnl_node. Make sure to use the rosarnl_node topic names, or for transparent compatibility with other ros tools, remap them. For example, to publish a 2D Nav Goal from rviz, change the topic name in the 2D Nav Goal Tool Properties in rviz.

• /rosarnl_node/move_base_simple/goal Publish a PoseStamped message to this topic to set a goal. ARNL will begin navigating to this goal if possible.
• /rosarnl_node/goalname Publish a string message to this topic to set a goal by name from the ARIA map.
• /rosarnl_node/move_base/goal, rosarnl_node/move_base/cancel, rosarnl_node/move_base/status and rosarnl_node/move_base/result. move_base compatible actionlib interface to request goals. See http://wiki.ros.org/move_base.
• /rosarnl_node/amcl_pose Subscribe to this topic to receive current localized position of robot in map as PoseWithCovarianceStamped messages.
• /rosarnl_node/initialpose Publish a PoseWithCovarianceStamped message to this topic to change position of robot from which ARNL will continue localizing.
• /rosarnl_node/global_localization Service which when called, performs an intial localization, assuming robot is either at last known position (as stored by ARNL), or at a "home" position in the map. (Note, this differs from the amcl node, which tries many possible positions across whole map.)
• /rosarnl_node/current_goal: ARNL's most recently requested goal point, as a Pose.
• /rosarnl_node/arnl_path_state: String name indicating changes to the the ARNL path planner internal state. See ArPathPlanningInterface::getState in the ARNL API Reference documentation
• /rosarnl_node/load_map_file: Service which loads a new map file. This is a shortcut to modifying the ARNL configuration with the new file name. Provide a string with the service request containing the file name of the map relative to ARNL's map directory (currently fixed at /usr/local/Arnl/examples but may be changed in the future) on the system running rosarnl_node. For example, using rosservice on the command line: rosservice call /rosarnl_node/load_map_file columbia.map
• /rosarnl_node/make_plan: Service which plans a path to the given goal goal point, but which does not start driving the robot on that path. A point sequence representing the path is returned. This plan will not incorporate sensed obstacles, just static map data.

The rosarnl node dosen't provide map data directly. This may be added in the future.

Jog Position mode

This mode can be used to do short discrete movements of the robot.

• /rosarnl_node/jog_position_simple/goal: Publish a geometry_msgs/Pose2D message to this topic to move a short discrete distance in X or Theta (Y is not yet implemented). Some obstacle sensing is attempted, configure in ARNL configuration (parameter file or via MobileEyes).
• /rosarnl_node/jog_position/goal: Initiate an Action Server action with a new Jog Position mode goal. Result is sent back when finished, cancel if interrupted.

Laser Data

Laser data is published (e.g. to see it in rviz). Laser connections are configured in the robot parameter file in /usr/local/Arnl/params. See <>.

Laser data is published similar to rosaria. For each connected laser, /rosarnl_node/lasername_pointcloud and /rosarnl_node/lasername_laserscan topics are published with sensor_msgs/PointCloud and sensor_msgs/LaserScan messages respectively, where lasername is ARIA's identifier for the laser. For example, lms2xx_1, lms1xx_1, etc.

Bumper Data

Bumper data is published via BumperState type messages on the /rosarnl_node/bumper_state topic. Messages contain two arrays of boolean flags indicating which bumper switches were recently pressed:

bool[] front_bumpers bool[] rear_bumpers

See robot documentation for locations of bumper switches.

The BumperState message type is defined by the rosarnl package as /rosarnl/BumperState (BumperState.msg).

Battery Data

Battey state information is published via BatteryStatus messages on the /rosarnl_node/battery_status topic. Messages contain two fields:

int8 charging_state float32 charge_percent

The value given for charging_state is one of:

CHARGING_UNKNOWN = -1 CHARGING_NOT = 0 CHARGING_BULK = 1 CHARGING_OVERCHARGE = 2 CHARGING_FLOAT = 3 CHARGING_BALANCE = 4

This message type is defined by the rosarnl package as rosarnl/BatteryStatus (BatteryStatus.msg).

Misc

• /rosarnl_node/arnl_server_mode topic: String with the current server mode name
• /rosarnl_node/arnl_server_status topic: String with the current server status message
• /rosarnl_node/enable_motors and /rosarnl_node/disable_motors topics: Services which enable/disable the robot motors.
• /rosarnl_node/motors_state topic: Subscribe to this topic to receive current state of motors as a Bool message which is true if enabled, false if disabled.
• /rosarnl_node/stop service: Call this service to enter stop mode. Any goals are interrupted and robot is decelerated to a stop.
• rosarnl_node/dock service: Call this service to enter dock mode. The robot stops, then navigates to a docking station to recharge (if the location of one is present in the map as a Dock point. See ARNL configuration e.g. via MobileEyes for more docking parameters.)

Transforms published via tf

ARNL publishes tf messages for transform from map to base_link using the localized robot pose. This is the same as the pose (amcl_pose) relative to the global map frame.

move_base-compatible actionlib interface

Goals can be sent, cancelled, etc to rosarnl_node/move_base/goal via actionlib as pose messages, similar to move_base from the standard ROS navigation stack. The move_base action message types are used, install move_base_msgs for client API (e.g. sudo apt-get install ros-jade-move-base-msgs for ROS Jade; The rosarnl package also declares a dependency on move_base_msgs so you can install with rosdep as well. (rosdep install rosarnl).

rostopic and rosservice examples

To quickly test or try out rosarnl, you can use the rostopic tool. rosarnl_node must be running, and a map must have been loaded into ARNL using MobileEyes.

List all available topics in the ROS master:

rostopic list

Trigger initial localization:

rosservice call /rosarnl_node/global_localization

Check the rosarnl_node log and MobileEyes to see if successful.

Monitor current position:

rostopic echo /rosarnl_node/amcl_pose

Send to a goal point using move_base_simple interface (no actionlib):

rostopic pub -1 /rosarnl_node/move_base_simple/goal geometry_msgs/PoseStamped '{header: {stamp: now, frame_id: "map"}, pose: {position: {x: 1.0, y: 1.0}, orientation: {w: 1.0}}}'

Check the ARNL status and pose topics, node log, or MobileEyes to see if successful.

Send to a goal point using move_base actionlib interface:

rostopic pub -1 /rosarnl_node/move_base/goal geometry_msgs/PoseStamped '{header: {stamp: now, frame_id: "map"}, pose: {position: {x: 1.0, y: 1.0}, orientation: {w: 1.0}}}'

Watch the /rosarnl_node/move_base/result topic for status.

Check if motors are enabled:

rostopic echo /rosarnl_node/motors_state

Enable motors if disabled:

 rosservice call /rosarnl_node/enable_motors

Send to a goal using goalname:

rostopic pub -1 /rosarnl_node/goalname std_msgs/String "GoalName"

Turn 90 degrees:

rostopic pub -1 /rosarnl_node/jog_position_simple/goal geometry_msgs/Pose2D '{pose: {orientation: {w: 1.0, z: 1.571}}}'

Move forward half a meter:

rostopic pub -1 /rosarnl_node/jog_position_simple/goal geometry_msgs/Pose2D '{pose: {position: {x: 0.5}}}'

For examples of sending messages and controlling actions from clients written in Python, see the client example python scripts in this directory.

TODO

More testing.

Provide laser and sonar data. Provide teleoperation (velocity) command interface. (maybe refactor rosarnl and rosaria to easily extend/incorporate everything from rosaria?)

Provide map.

Are published tf's useful? should they be configurable?