HamsterPython
Python setup
- Note you are on the HamsterNet
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$ export ROS_IP=<your IP>
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$ export ROS_MASTER_URI=http://10.0.2.<HAMSTER AGENT Number>:11311
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Python Example 1
- Receive laser scan from robot to decide if free
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- !/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')
- Put your Hamster number instead of agent<number>
- The agent number is printed on the Hamster cover
sub = rospy.Subscriber('/agent14/scan', LaserScan, callback)
rospy.spin()
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- !/usr/bin/env python
import rospy import math from sensor_msgs.msg import Imu from tf.transformations import euler_from_quaternion, quaternion_from_euler
def calculate_robot_angle(orientation): quaternion = ( orientation.x, orientation.y, orientation.z, orientation.w) euler = euler_from_quaternion(quaternion) roll = euler[0] pitch = euler[1] yaw = euler[2] return math.degrees(yaw)
prev_angle = 0 def callback(msg): global prev_angle curr_angle = calculate_robot_angle(msg.orientation) if curr_angle > prev_angle : print "TURINING LEFT" else: print "TURINIGN RIGHT" prev_angle = curr_angle
rospy.init_node('imu_values')
last_angle = 0
- Put your Hamster number instead of agent<number>
- The agent number is printed on the Hamster cover
sub = rospy.Subscriber('/agent14/imu', Imu, callback)
rospy.spin()
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