Turtlebots

#! usr#!/usr/bin/env python

import rospy
from sensor_msgs.msg import LaserScan
from geometry_msgs.msg import Twist




def callback(msg):
    print('=========================')
    print('s1 [0]')
    print(msg.ranges[0])  #distance at angle 0, which is directly in front of robot

    print('s2 [90]')
    print(msg.ranges[90])  #distance at angle 90 degrees

    print('s3 [180]')
    print(msg.ranges[180])  #distance at angle 180 degrees

    print('s4 [270]')
    print(msg.ranges[270])  #distance at angle 270 degrees

    print('s5 [359]')
    print(msg.ranges[359])  #distance at angle 359 degrees


    c1 = 0
    c2 = 0
    a1 = 345
    a2 = 0
    while a1 < 359:
        a1 += 1
        r = msg.ranges[a1] > 0.3
        if r == False:
            c1 += 1

    while a2 < 15:
        a2 += 1
        r = msg.ranges[a2] > 0.3
        if r == False:
            c2 += 1

    if c1 > 0 or c2 > 0:
        move.linear.x = 0.0
        move.angular.z = 0.0
        print('Obstacle in front')
        print("Turning")
        move.linear.x = 0.0
        move.angular.z = 0.22
        if msg.ranges[90] > 0.5:
            move.linear.x = 0.0
            move.angular.z = -0.22


    else:
        move.linear.x = 0.22
        move.angular.z = 0.0
        print('Moving Forward')


    pub.publish(move)


rospy.init_node('obstacle_avoidance')                          #Initiate node
sub = rospy.Subscriber('/scan', LaserScan, callback)    #Create subscriber to laser/scan topic
pub = rospy.Publisher('/cmd_vel', Twist)
move = Twist()

rospy.spin()