Collision-Avoidance-car

This is a ROS package for collision avoidance Rpi car.

Hardware description

RPI model 3 with Ubuntu mate 18.04 OS
Arduino Uno
DC motor with encoder
RpLidar A1

Preparation

ROS melodic
ROS serial download

System implementation

Package description

motor_iface.ino

This file conteains motor controls code to DC motor. Including a pair of PID controller for both wheels, a ROS serial topic for receiving PWM value from RPi, encoder receiver and publishing wheel velocity to Rpi.

src/odom.cpp

Receiving wheels velocity from Arduino, and integrating them to wheel odometry for localization.

tf_publisher.cpp

Receiving wheel odometry from odom.cpp, and publishing it to tf.

obstacle_detect.cpp

Receiving point cloud from RpLidar, removing noisy points, and clustering continuous point as obstacle. Calculating the nearest obstacle as repulsive force generation point.

potential_field.cpp

Generating repulsive force from the nearest obstacle, attractive force from the goal. Convert the desired velocity to PWM value of two wheels by inverse Kinematics.

Run the code

Run up RpLidar node first.
Start localization node.

roslaunch [pkg_name] localization.launch

Should modify USB port of Arduino.

Start main node.