HamsterPythonExample1

Python Example 1

• Receive laser scan from robot to decide if free

<syntaxhighlight lang="python" line='line'>

1. !/usr/bin/env python

import rospy from sensor_msgs.msg import Imu

def is_free(ranges ,start_index, end_index ,min_distance): #sub array from angle to angle s_ranges = ranges[start_index:end_index] #filter the array b_ranges = filter(lambda x: x <= min_distance, s_ranges) return len(b_ranges) == 0

def callback(msg): if is_free(msg.ranges,160,200,0.2): print "FREE" else: print "BLOCKED"

rospy.init_node('scan_values')

1. Put your Hamster number instead of agent<number>
2. The agent number is printed on the Hamster cover

sub = rospy.Subscriber('/agent14/scan', LaserScan, callback)

rospy.spin()

</syntaxhighlight>

To execute save this example in example1.py and type in the terminal

<syntaxhighlight lang="bash" line='line'>

$ python example1.py

</syntaxhighlight>