segway_node.py

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#! /usr/bin/python
# Copyright (c) 2009, Georgia Tech Research Corporation
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#  \author Hai Nguyen (Healthcare Robotics Lab, Georgia Tech.)
#  \author Marc Killpack (Healthcare Robotics Lab, Georgia Tech.)

import roslib; roslib.load_manifest('hrl_segway_omni')
from hrl_lib.msg import PlanarBaseVel
from geometry_msgs.msg import Twist
import rospy
import segway
import numpy as np

def callback(cmd):
    #print 'segway_node:', cmd.xvel, cmd.yvel, cmd.angular_velocity
    mecanum.set_velocity(cmd.xvel, cmd.yvel, cmd.angular_velocity)

def callback_ros(cmd):
    #print 'segway_node:', cmd.linear.x, cmd.linear.y, cmd.angular.z
    avel = cmd.angular.z * 0.5
    avel = np.clip(avel,-0.2,0.2)
    mecanum.set_velocity(cmd.linear.x, cmd.linear.y, avel)

rospy.init_node("segway_node", anonymous=False)
rospy.Subscriber("base", PlanarBaseVel, callback, None, 1)
rospy.Subscriber("cmd_vel", Twist, callback_ros, None, 1)
#mecanum = segway.Mecanum(init_ros_node=False)
mecanum = segway.Mecanum()
rospy.spin()