[KUSMO] 10/29

1) Setting ROS Navigation Stack

• The ROS Navigation Stack is a collection of software packages that you can use to help your robot move from a starting location to a goal location safely.
• Below is the official steps for setup and configuration, but the blog explains it all, because that link leave out a lot of detail
• http://wiki.ros.org/navigation/Tutorials/RobotSetup 

 

$ sudo apt-get install ros-noetic-navigation

• Install ROS Navigaion Stack

$ rospack find amcl

• Check if it installed correctly
• if output is 'opt/ros/noetic/share/amcl', it is right

 

- Create a Package

$ cd ~/catkin_ws/src/
$ mkdir kusmo_bot

• Make folder where we will create a package
• I named the folder`s name with my team`s name

 

$ cd ~/catkin_ws/src/kusmo_bot

• Open a new terminal and type above`s code

$ catkin_create_pkg navstack_pub rospy roscpp std_msgs tf tf2_ros geometry_msgs sensor_msgs nav_msgs move_base

• Create a package named navstack_pub

 

$ roscd navstack_pub
$ mkdir param

• Go inside to navstack_pub package, and add a folder named param

 

$ roscd navstack_pub
$ gedit CMakeLists.txt

• Go back to our package, and Open CMakeLists.txt
• Remove the hashtag on line 5 to make sure that C++11 support is enabled

 

• Save and close the file

 

- Compile the package

$ cd ~/catkin_ws/
$ catkin_make --only-pkg-with-deps navstack_pub

• Open a new terminal window and move to our navstack_pub package

 

$ roscd navstack_pub
$ mkdir launch 
$ cd launch

• Open a new terminal window and move to our navstack_pub package

gedit kusmo_bot.launch

• Create our launch file and add the following code

<launch>
</launch>

• Save the file and close it

 

- Transform Configuration

$ roscd navstack_pub
$ cd launch

• Open a new terminal window and type above codes

$ gedit kusmo_bot.launch

• Open our launch file and add the following code
• https://drive.google.com/file/d/1Ffkb-rT7-VMbUrXFRE11XxkgAhf1_N_G/view 
• We need to modify it for our own robot

 

 

- HOW TO MODIFY IT

• We need to set up coordinate frames for our two-wheeled diffenetial drive mobile robot(kumo)

 

---

Modify Finished

 

- Create Common Configuration (Global and Local Costmap) File

• Create a configuration file that will house parameters that are common to both the global and the local costmap
• The name of this file will be 'costmap_common_params.yaml.'

 

$ cd ~/catkin_ws
$ roscd navstack_pub
$ cd param
$ gedit costmap_common_params.yaml

• Open costmap_common_params.yaml and add following codes

obstacle_range: 0.5
raytrace_range: 0.5
footprint: [[-0.14, -0.14], [-0.14, 0.14], [0.14, 0.14], [0.14, -0.14]]
map_topic: /map
subscribe_to_updates: true
global_frame: odom
robot_base_frame: base_link
update_frequency: 30.0
publish_frequency: 30.0
rolling_window: false

plugins:
  - {name: static_layer, type: "costmap_2d::StaticLayer"}
  - {name: obstacle_layer, type: "costmap_2d::ObstacleLayer"}
  - {name: inflation_layer, type: "costmap_2d::InflationLayer"}

static_layer:
  map_topic: /map
  subscribe_to_updates: false

obstacle_layer:
    observation_sources: laser_scan_sensor
    laser_scan_sensor: {sensor_frame: laser, data_type: LaserScan, topic: scan, marking: true, clearing: true}

inflation_layer:
  inflation_radius: 0.2

- Add the meanings of each parameters : http://wiki.ros.org/navigation/Tutorials/RobotSetup

 

 

- Create Global Configuration (Global Costmap) File

• Create a configuration file that will house parameters for the global costmap
• The name of this file will be 'global_costmap_params.yaml.'
• Assume that we are in the same directory as above ( /home/lim/catkin_ws/src/kusmo_bot/navstack_pub/param )

$ gedit global_costmap_params.yaml

• Open global_costmap_params.yaml and add following codes

global_costmap:
  global_frame: odom
  update_frequency: 30.0
  publish_frequency: 30.0
  transform_tolerance: 0.2
  resolution: 0.1

 

 

- Create Local Configuration (Local Costmap) File

• Create a configuration file that will house parameters for the local costmap
• The name of file will be 'local_costmap_params.yaml.'

 

$ gedit local_costmap_params.yaml

• Assume that we are in the same directory, and open local_costmap_params.yaml file
• Add the following codes to that file

local_costmap:
  update_frequency: 30.0
  publish_frequency: 30.0
  transform_tolerance: 0.2
  static_map: false
  rolling_window: true
  resolution: 0.1
  inflation_radius: 0.1
  width: 1.0
  height: 1.0

  plugins:
    - {name: obstacle_layer, type: "costmap_2d::ObstacleLayer"}

  obstacle_layer:
    observation_sources: laser_scan_sensor
    laser_scan_sensor: {sensor_frame: laser, data_type: LaserScan, topic: scan, marking: true, clearing: true}

 

 

• In addtion to the costmap configurations we did in the previous section, we need to configure ROS Navigation`s Stack`s base local planner, which computes velocity commands that are sent to the robot base controller
• The values that we use for base_local_planner will depend on our robot

- Add explain of base_local_planner package : http://wiki.ros.org/base_local_planner

$ gedit base_local_planner_params.yaml

• Assume that we are in the same directory above, open base_local_planner_params.yaml file and add the following codes

TrajectoryPlannerROS:
  max_vel_x: 0.12
  min_vel_x: 0.11
  #max_vel_theta: 0.05
  #min_vel_theta: -0.05
  #min_in_place_vel_theta: 0.05

  #acc_lim_theta: 0.07
  #acc_lim_x: 0.25
  #acc_lim_Y: 0.25

  holonomic_robot: false

  meter_scoring: true

  xy_goal_tolerance: 0.15
  yaw_goal_tolerance: 0.25

 

 

• Now we have created our configuration files, we need to add them to the launch file
• The configuration files will be used by ROS Navigation Stack`s move_base node

- Add the explain of move_base package : http://wiki.ros.org/move_base

 

 

- Move Base Node

• The move_base node is the workhorse behind the scenes that is responsible for planning a collision-free path from a starting location to a goal location for a mobile robot
• The move_base node subscribes to the following topics :
• /move_base_simple/goal :  Goal position and orientation (geometry_msgs::PoseStamped). The messages on this topic are generated using the goal button on RViz.

• The publisher will publish to the following topics :
• /cmd_vel : Linear and angular velocity command (geometry_msgs/Twist Message)

 

$ cd ~/catkin_ws
$ roscd navstack_pub
$ cd launch
$ gedit kusmo_bot.launch

• Add the "Move Base Node" block of https://drive.google.com/file/d/1Ffkb-rT7-VMbUrXFRE11XxkgAhf1_N_G/view
• It loads all the configuration files we have created so far, and also loads the move_base node

 

 

- AMCL Configuration

• The ROS Navigation Stack requires the use of AMCL (Adaptive Monte Carlo Localization), a probabilistic localization system for a robot
• AMCL is used to track the pose of a robot against a known map. It takes as input a map, LIDAR scans, and transform messages, and outputs an estimated pose

- Add the explain of amcl package : http://wiki.ros.org/amcl

 

• The amcl node subscribes to the following topics :
• /scan :  Laser scan messages from the LIDAR (sensor_msgs/LaserScan).

• /tf : Coordinate frame transformations (tf/tfMessage)

• /initialpose : The initial position and orientation of the robot using quaternions. (geometry_msgs/PoseWithCovarianceStamped) — RViz initial pose button publishes to this topic.

• /map : The occupancy grid map created using gmapping, Hector SLAM, or manually using an image (nav_msgs/OccupancyGrid)

 

• The amcl node will publish to the following topics :
• /amcl_pose : Robot’s estimated pose in the map (geometry_msgs/PoseWithCovarianceStamped)

• /particlecloud: The set of pose estimates being maintained by the filter (geometry_msgs/PoseArray)

• /tf (tf/tfMessage): Publishes the transform from odom (which can be remapped via the ~odom_frame_id parameter) to map

 

$ cd ~/catkin_ws
$ roscd navstack_pub
$ cd launch 
$ gedit kusmo_bot.launch

• Add the "Add AMCL example for differential drive robots" blocks of the same code as above to launch file
• It loads the ACML code for a differential drive robot

 

- Launch the Autonomous Mobile Robot

 

$ cd ~/catkin_ws/
$ catkin_make --only-pkg-with-deps navstack_pub

• Complie the package
• Turn on the motors of robot

 

$ roslaunch navstack_pub jetson_nano_bot.launch

• Open a new terminal and launch the launch file

 

 

 

 

 

• When we know the radius of each wheel, we can use tick data and the wheel radius data to determine the distance traveled by each wheel. Below is the equation for that
• Distance a wheel has traveled = 2 * pi * radius of the wheel * (number of ticks / number of ticks per revolution)

 

 

 

 

 

 

 

---

References :

https://automaticaddison.com/how-to-set-up-the-ros-navigation-stack-on-a-robot/

How to Set Up the ROS Navigation Stack on a Robot – Automatic Addison