ROS Line Follower

Brief

The robot runs ROS on Raspberry Pi, using usb camera and opencv library to detect the line and an Arduino to control the wheels by PID.

Architecture

@startuml
!pragma teoz true

camera -> Line_detector : img
Line_detector -> Coachman : img, contours, points
Coachman -> toarduino : pwm_msg
camera -> recorder : img
Coachman -> recorder : img
toarduino -> motor_controll : pwm_msg
motor_controll -> wheels : pwm

box "ROS NODES"
  participant camera
  participant recorder
    box "detector"
      participant Line_detector
      participant Coachman
    endbox
  participant toarduino
endbox

box "ARDUINO"
  participant motor_controll
  participant wheels
@enduml

Commands

1. To launch

roslaunch detector detector.launch 

2. To view the image

rqt_image_view

3. To view the node graph

rosrun rqt_graph rqt_graph

4. To upload to ardunio

cd ~/Line_follower/onArdu/Line_follower
make upload clean

Devlog

3/17
Fix uart delay problem

3/13
Test on Pi
Couldn't reduce the period from arduino echo to the new msg arrived
It might caused by the while in toarduino.py for waiting the arduino echo

3/8
Optimize motor controll
Add recorder node

3/5
Optimize line detect

3/3
Fuck up raspberry

3/2
PID controll

2/20
Update line detect

2/19
Test Rasberry pi

2/18
Toarduino pkg

2/17
Line detect and camera pkg

ToDo

Tweak motor speed
Test on Pi
Adjust PID parameters
Check if the Arduino receieve the msg
Optimize the line detector

Reference

Canny
HoughLines
HoughLines vs HoughLinesP
Line detect algorithm
Upload to arduino using terminal