Introduction: Using RPlidar With Robot Navigation
Hi everyone !
we made a project consist of Using RPlidar With Robot Navigation .
we will explain how dose this project work , so we used the RPlidar to build the map that will follow by the robot.
thus, follow our lead to make this project run.
Step 1: Components
1- A Raspberry pi 4 (8GB)
2- A 16GB or higher capacity microSD card
3- A keyboard and a mouse
4- A micro-HDMI to HDMI cable
5- wired network for connecting the Raspberry Pi to the internet(Ethernet)
6-A USB Type-C power adapter for Raspberry Pi 4
7- RPlidar
8- Cable
9-Arduino
10-Robot 4 Weel Car Chassis Kit
11- L298N driver module
12-Wires
13-Baterry 12V 2A
Step 2: Download Ubuntu 16.04
To Download we chose 2020-11-07-ubiquity-xenial-lxde
Step 3:
Step 4: Start With Ubuntu 16.04
This system has already Ros kinetic. Therefore, we started with Connect to the WiFi
network that starts with ubiquityrobot. Password is robotseverywhere. Go to Terminal, and connect to your Pi using ssh ubuntu@10.42.0.1. Password is ubuntu.
Note: If you want to use another version of ubuntu follow this link
https://www.instructables.com/Using-Raspberry-Pi-4-With-Ubuntu-Ros-Rplidar-Ardui/
Then run
sudo systemctl disable magni-base
to ensure that startup scripts are disabled.
Run roscore to make sure that things are working properly.
roscore
If you get warning/errors, try stopping ROS and starting it again with
killall -9 roscore
Run
roscore
Step 5: Cmake Upgrade
So we will start by install the cmake 3.7.2 Installation by a PPA (Upgrade to 3.7)
Open terminal and run:
sudo apt-get install software-properties-common
sudo add-apt-repository<br>ppa:george-edison55/cmake-3.x
sudo apt-get update
When cmake is already installed
sudo apt-get upgrade
sudo apt-get install build-essential
wget <a href="http://www.cmake.org/files/v3.7/cmake-3.7.2.tar.gz" rel="nofollow"> http://www.cmake.org/files/v3.7/cmake-3.7.2.tar.g...</a>
tar xf cmake-3.7.2.tar.gz
cd cmake-3.7.2
./configure
make
sudo apt-get install checkinstall
sudo checkinstall
sudo make install
Step 6: Rplidar Kinetic Installation
cd catkin_ws
cd src
git clone <a href="https://github.com/Slamtec/rplidar_ros.git" rel="nofollow"> https://github.com/Slamtec/rplidar_ros.git</a>
cd ..
catkin_make
Check the authority of rplidar's serial-port
ls -l /dev |grep ttyUSB
Add the authority of write: (such as /dev/ttyUSB0)
sudo chmod 666 /dev/ttyUSB0
Start a rplidar node and view the scan result in rviz.
roslaunch rplidar_ros view_rplidar.launch
Step 7: Hector Slam
The hector-mapping nodes depend on Qt4, so you
need to install it first.
sudo apt-get install qt4-qmake qt4-dev-tools
Move into catkin_ws/src, clone the source files and then make them
cd catkin_ws
cd src
git clone <a href="https://github.com/tu-darmstadt-ros-pkg/hector_slam.git" rel="nofollow">https://github.com/tu-darmstadt-ros-pkg/hector_sla...</a>
cd ..<br>
catkin_make
Step 8: File Modify
For a quick test of the hector_mapping two launch files needs to be modified.
Edit the "mapping_default.launch" file
Run
nano ~/catkin_ws/src/hector_slam/hector_mapping/launch/mapping_default.launch
Modify the third line to this
<arg name="base_frame" default="base_link"/>
And the fourth line to this.
<arg name="odom_frame"default="base_link"/>
The last line to this
<node pkg="tf"type="static_transform_publisher" name="base_to_laser_broadcaster" args="0 0 0 0 0 0 base_link laser 100" />
Step 9: Another File Modify
edit the "tutorial.launch" file
nano ~/catkin_ws/src/hector_slam/hector_slam_launch/launch/tutorial.launch
and replace the third line to look like so
<param value="false"><param><param name="/use_sim_time" value="false"/><br>
NOTE: when you want to start the mapping process you should run the rplidar in another terminal.
roslaunch rplidar_ros view_rplidar.launch
roslaunch rplidar_ros view_rplidar.launch
Step 10: Arduino With Kinetic
Start with Arduino IDE installed, download it from the Arduino website
Go to software > download > in the right side choose linux32 After finish, extract the file on download. Open the terminal and write this code:
sudo apt-get install ros-kinetic-rosserial-arduino
To Install the IDE :
cd Downloads
cd arduino-1.8.13
sudo ./install.sh
install rosserial
cd catkin_ws
cd src
git clone <a href="https://github.com/ros-drivers/rosserial.git" rel="nofollow"> <a href="https://github.com/ros-drivers/rosserial.git" rel="nofollow"> https://github.com/ros-drivers/rosserial.git </a> </a>
<a href="https://github.com/ros-drivers/rosserial.git" rel="nofollow"></a>cd ..
catkin_make
catkin_make install
Install ros_lib into the Arduino Environment
cd snap
cd arduino
cd current
cd arduino
cd libraries
rm -rf ros_lib
rosrun rosserial_arduino make_libraries.py
Open a new terminal window and type:
ls - l /dev/ttyACM0
after that run
sudo chmod a+rw /dev/ttyACM0
again run
ls - l /dev/ttyACM0
Step 11: Robot Control
The entirety of the code for this node lives on the Arduino. So we use this sketch, and upload it. This is a very very simple sketch, that only supports forward and stopping motion.
We can control the robot from our raspberry pi now! In separate terminal instances, run the following:
Allow Arduino communication with
rosrun rosserial_python serial_node.py /dev/ttyACM0
Enable keyboard control with:
rosrun teleop_twist_keyboard teleop_twist_keyboard.py
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