Final version with comments

map.yaml

@@ -1,7 +0,0 @@
-image: /home/kilian/map.pgm
-resolution: 0.050000
-origin: [-10.000000, -10.000000, 0.000000]
-negate: 0
-occupied_thresh: 0.65
-free_thresh: 0.196
-

src/autopilot.py

@@ -1,14 +1,49 @@
 #!/usr/bin/env python
-import rospy
+#Previous line made to interpret the code in Python
+
+'''
+Autopilot script
+
+ROS script that creates a node called autopilot. This node make a Turtlebot3 have a roomba behavior to ease SLAM process.
+The robot goes in straight line until an obstacle is detected too close, then turn of a random value and goes in a straight line.
+The process then store the relative position estimated by the odom topic when received and sum it.
+When this value outgrows a treshold, the process stops.
+
+This node subscribes to the topic /scan & /odom
+This node publishes to the topic /cmd_vel
+
+author: Kilian Declercq, kilian.declercq@ecam.fr, Thomas Boutant, thomas.boutant@ecam.fr, 
+date: 27/11/2022
+'''
+
+#Python imports
 import numpy as np
 import random
+
+#ROS imports (rospy & msgs type)
+import rospy
 from std_msgs.msg import String
 from geometry_msgs.msg import Twist
 from sensor_msgs.msg import LaserScan
 from nav_msgs.msg import Odometry
 
-distancemin = 0.4
+# Definition of the constants & variables
-inittmp = [0,0]
+distancemin = 0.4 	# Distance of detection at which the robot stops and turn
+init = [0,0]		# Initialisation of position coordinates for callback2
+dist_covered =[]	# Array that store all the covered distances
+
+
+# ...
+
+'''
+Function: publish_move(move):
+
+Task: 	Publish a message to the cmd_vel topic
+
+Inputs:
+		- move: message of type Twist
+   	   (-pub: could put pub as input to avoid redefining the node publisher at every call of publish_move)
+'''
 
 def publish_move(move):
 	rate = rospy.Rate(10)
@@ -16,6 +51,21 @@ def publish_move(move):
 	pub.publish(move)
 	rate.sleep()
 
+
+# ...
+
+'''
+Function: callback1(move):
+
+Task: 	When data is received by the /scan topic, detect if in object in a range of 60° in front of 
+		the robot is under the treshold distance. 
+		If is not the case, publish a x linear move with publish_move() and print 'forward'
+		If this is the case, publish a z angular move with publish_move() and print 'Turn'
+
+Inputs:
+		- data: message of type LaserScan
+'''
+
 def callback1(data):
 	move = Twist()
 	distance = min(data.ranges[0:29] and data.ranges[329:359])
@@ -32,9 +82,21 @@ def callback1(data):
 		print('turn')
 		publish_move(move)
 
-dist_covered =[]
 
-def callback2(data,init = inittmp):
+# ...
+
+'''
+Function: callback2(move):
+
+Task: 	When data is received from the odom sensor, compare it to the previous position and extract the travelled distance.
+		Append traveled distance to the dist_covered array. When the sum of the array overcome the treshold value, stop the process.
+
+Inputs:
+		- data: message of type Odometry
+'''
+
+def callback2(data):
+	global init
 	rate = rospy.Rate(10)
 	pos =[data.pose.pose.position.x,data.pose.pose.position.y]
 	tmp = np.linalg.norm(np.array(init)-np.array(pos))
@@ -42,7 +104,7 @@ def callback2(data,init = inittmp):
 	init = pos
 	print("The distance covered %s" %sum(dist_covered))
 		
-	if sum(dist_covered) >= 20000:
+	if sum(dist_covered) >= 200:
 		stop = Twist()
 		stop.angular.z = 0
 		stop.linear.x = 0
@@ -53,15 +115,30 @@ def callback2(data,init = inittmp):
 	rate.sleep()
 
 
+
+# ...
+
+'''
+Function: autopilot():
+
+Task: 	Subscribe our autopilot node to /scan & /odom topics, and call respectives callback functions
+
+Inputs:
+		- data: message of type Odometry
+		- init = inittmp: for the first initialisation of the loop provide an initial array
+'''
+
 def autopilot():
 	rospy.Subscriber("scan", LaserScan, callback1)
 	rospy.Subscriber("odom", Odometry, callback2)
 	rospy.spin()
 
 
+# ...
+
 if __name__ == '__main__':
-	rospy.init_node('autopilot', anonymous = True)
+	rospy.init_node('autopilot', anonymous = True)  # Initialise our node
-	autopilot()
+	autopilot()										# Launch autopilot() function