/robot_control

Primary LanguagePython

robot_control

OverView

This is the package to control a holonomic robot in a 2d space with a simple 2d simulator, Stage.

The robot's behavior:

  1. The robot asks for a random target, with both coordinates in the interval (-6.0, 6.0).
  2. Check whether the robot reaches the target or not.
  • If true, Go to step 1.
  • If not, Go to step 3.
  1. Send the velocity depending on the distance between the target and current position of the robot. Go to 2.

Description of the content of the package

Nodes

  • robot_simulator
    • Client of the '/random_target'
    • Publisher of '/cmd_vel'
    • Subscriber of 'odom'
  • target_server
    • Server of '/random_target'
  • stageros
    • Publisher of 'odom'
    • Subscriber of 'cmd_vel'
    • and so on.

Topic

  • /cmd_vel
    • Type: gemetry_msgs/Twist
    • Publisher : /robot_simulator
    • Subscriber: /stage_ros
  • /odom
    • Type: nav_msgs/Odometry
    • Publisher : /stage_ros
    • Subscriber:/robot_simulator

Service

  • /random_target
    • Node :target_server
    • Type : robot_control/RandomPos
    • Args: min, max

custom service

  • robot_control/RandomPos

  • request

    • float32 min
    • float32 max

  • response

    • float32 x
    • float32 y

Computational graph of the system

  • robot simulator
    • subscribe /odom from node "stageros", and depending on the current position, decide the velocity and publish it as /cmd_vel
    • When the robot reach the goal, this node send the service to the node "target_server"and receive the robot new target position.
  • target_server
    • "target_server" get service from "robot_simulator" and send this node the new target position.

rosgraph

Installation

Dependencies

This software is built on the Robotic Operating System ([ROS]), which needs to be install first and create the workspace.

  • Ros Kinetic

Building

This package use the package "stage_ros".

In order to install this,

sudo apt-get install ros-<your_ros_version>-stage-ros

Install this package and the other necessary package into your workspace.

Compile the package using ROS.

cd catkin_workspace/src
git clone https://github.com/n-shintaro/robot_control.git
git clone https://github.com/CarmineD8/assignment1.git
cd ../
catkin_make
rospack profile

Usage

roscore &

This package requires controlling a holonomic robot in a 2d space with a simple 2d simulator, Stage. The simulator can be launched by executing the command.

rosrun stage_ros stageros $(rospack find assignment1)/world/exercise.world

To run the node (robot_simulator),

rosrun robot_control robot_simulator.py

To run the node (target_server),

rosrun robot_control target_server.py