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Only released in EOL distros:   indigo

Overview

The nj_costmap package implements a navigation jockey for the Large Maps Framework (LaMa) based on a local costmap such as those provided by the local_map package (costmap position is relative to the sensor but orientation is absolute).

The role of this jockey is to travel to the next crossing. The action is done when the robot reaches the crossing center. It is considered to be memory-less because it uses only an internal memory (in form of a local map) and do not interact with the large map.

Implemented actions:

• TRAVERSE: will start navigating to the next crossing (place with at least three frontiers) and will succeed when the crossing center is reached.
• STOP: will stop
• INTERRUPT: same as STOP
• CONTINUE: same as TRAVERSE

Usage

ROS API

Subscribed Topics

~<name>/local_costmap (nav_msgs/OccupancyGrid)

• local cost map which orientation is global

Published Topics

~<name>/cmd_vel (geometry_msgs/Twist)

• robot set velocity

~<name>/crossing_marker (visualization_msgs/Marker)

• a sphere at the crossing center.

~<name>/exits_marker (visualization_msgs/Marker)

• lines from crossing center towards exits.

~<name>/ place_profile (sensor_msgs/PointCloud)

• point cloud representing the place profile.

~<name>/abs_crossing (lama_msgs/Crossing)

• Crossing with absolute frontier angles

Parameters

~<name>/odom_frame (String, default: "/odom")

• this is the laser scan frame from which the map relative orientation is computed

~<name>/frontier_width (Float)

• free space through which the robot can go

~<name>/robot_radius (Float, default: ~frontier_width/2)

• robot radius

~<name>/laser_frame (String, default: "/base_laser_link")

• name of the laser scan frame for the obstacle avoider

~<name>/navigating_jockey_server_name (String, default: node_name "_server")

• Jockey name