ROS学习(2)--ROS项目试炼

This book is about learning ROS by examples. Due to the fact that ROS is not my preliminary thing that I just have a glimps to it. Overall, I just care about the basic concept about ROS and the implementation of self-driving car.

Basic concepts about ROS

ROS is what we called Robot Operation System, and it has been widly used in robot design and self-driving car design. I will illustrate the essential concepts by practice as the concepts in theory has been illustrate in the introduction file.

Installation

Download and install ROS from wiki.ros.org by following the instructions.

My choice is the full desktop version. However, I’ve faced with some accidental issues which trobled me a lot. And my solution is trying to reinstall my ubuntu on my computer. Luckily, it really helped.

ROS WORKSPACE

ROS workspace is the key part of ROS.

Next I will illustrate the procedure of creating a ROS workspace.

1. Create a new folder.

    cd ~
    mkdir -p catkin_ws/src
   

2. Write the code in src

    cd catkin_ws/src
    git clone(a painless way)
   

3. Initialize the workspace

    cd catkin_ws/src
    catkin_init_workspace
   

4. Compile the workspace

    cd ../
    catkin_make
   

If make successfully, then we can lauch a lauch file and then run the rviz(ROS Visualizer).

Face Detection and Tracking Using ROS, OpenCV and Dynamixel Servos

Follow the guide in Chapter 2 and then we can get the detection and tracking image successfully.

Attention: OpenCV has the interface for ROS and we can implement ROS file and then run it on OpenCV.

Creating a Self-Driving Car Using ROS

Levels of autonomy

• Level 0: Completely manual
• Level 1: Driver assistance system control the speed
• Level 2: Steering and acceleration/deceleration by vehicles
• Level 3: Conditional automation:
• Level 4: High automation.
• Level 5: Full automation. High robust.

Self-Driving Car implementation

Install the neccessary files

1. Install the ROS Gazebo controller manager.

   sudo apt-get install ros-kinetic-controller-manager
   sudo apt-get install ros-kinetic-ros-control ros-kinetic-ros-controllers
   sudo apt-get isntall ros-kinetic-gazebo-ros-control
   

2. Install the Velodyne simulator

Due to the fact that Velodyne simulator can not be installed automatically so that we use it by downloading it from github.

    download ros-kinetic-velodyne from github
    copy it into the src workspace
    in src reinitialize the file: catkin_init_workspace
    cd ../ then  catkin_make

1. Before make, clone two files into src

   git clone https://github.com/sprinkjm/catvehicle.git
   git clone https://github.com/sprinkjm/obstaclestopper.git
   

2. Add the workspace path into .bashrc

   source ~/catvehicle_ws/devel/setup.bash
   

3. Launch the vehicle simulation

   roslaunch catvehicle catvehicle_skidpan.launch
   gzclient
   

4. Launch the visualization file system

   rviz
   

Then we can see the visualization file.

It’s just the basic concepts and implementation of ROS, more tricks remains to be further studied.

The End.