Hi, I am new to PX4. I am trying to move a quad-copter using PX4 OFFBOARD_MODE using setpoint_local_position in an outdoor environment. I am using the following code to move the quad across a few waypoints and then land. The quad is successfully moving to the waypoint but not maintaining the z-axis. Every time I launch it visits the point at a new height. This code was taken from the tutorials of PX4.
How should I make it move through the given waypoints at the given height?
#!/usr/bin/env python2
#***************************************************************************
#
# Copyright (c) 2015 PX4 Development Team. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
# 3. Neither the name PX4 nor the names of its contributors may be
# used to endorse or promote products derived from this software
# without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
#***************************************************************************/
#
# @author Andreas Antener <andreas@uaventure.com>
#
# The shebang of this file is currently Python2 because some
# dependencies such as pymavlink don't play well with Python3 yet.
from __future__ import division
PKG = 'px4'
import rospy
import math
import numpy as np
from geometry_msgs.msg import PoseStamped, Quaternion
from mavros_msgs.msg import ParamValue
from mavros_test_common import MavrosTestCommon
from pymavlink import mavutil
from six.moves import xrange
from std_msgs.msg import Header
from threading import Thread
from tf.transformations import quaternion_from_euler
class MavrosOffboardPosctlTest(MavrosTestCommon):
"""
Tests flying a path in offboard control by sending position setpoints
via MAVROS.
For the test to be successful it needs to reach all setpoints in a certain time.
FIXME: add flight path assertion (needs transformation from ROS frame to NED)
"""
def setUp(self):
super(MavrosOffboardPosctlTest, self).setUp()
self.pos = PoseStamped()
self.radius = 1
self.pos_setpoint_pub = rospy.Publisher(
'mavros/setpoint_position/local', PoseStamped, queue_size=1)
# send setpoints in separate thread to better prevent failsafe
self.pos_thread = Thread(target=self.send_pos, args=())
self.pos_thread.daemon = True
self.pos_thread.start()
def tearDown(self):
super(MavrosOffboardPosctlTest, self).tearDown()
#
# Helper methods
#
def send_pos(self):
rate = rospy.Rate(10) # Hz
self.pos.header = Header()
self.pos.header.frame_id = "base_footprint"
while not rospy.is_shutdown():
self.pos.header.stamp = rospy.Time.now()
self.pos_setpoint_pub.publish(self.pos)
try: # prevent garbage in console output when thread is killed
rate.sleep()
except rospy.ROSInterruptException:
pass
def is_at_position(self, x, y, z, offset):
"""offset: meters"""
rospy.logdebug(
"current position | x:{0:.2f}, y:{1:.2f}, z:{2:.2f}".format(
self.local_position.pose.position.x, self.local_position.pose.
position.y, self.local_position.pose.position.z))
desired = np.array((x, y, z))
pos = np.array((self.local_position.pose.position.x,
self.local_position.pose.position.y,
self.local_position.pose.position.z))
return np.linalg.norm(desired - pos) < offset
def reach_position(self, x, y, z, timeout):
"""timeout(int): seconds"""
# set a position setpoint
self.pos.pose.position.x = x
self.pos.pose.position.y = y
self.pos.pose.position.z = z
rospy.loginfo(
"attempting to reach position | x: {0}, y: {1}, z: {2} | current position x: {3:.2f}, y: {4:.2f}, z: {5:.2f}".
format(x, y, z, self.local_position.pose.position.x,
self.local_position.pose.position.y,
self.local_position.pose.position.z))
# For demo purposes we will lock yaw/heading to north.
yaw_degrees = 0 # North
yaw = math.radians(yaw_degrees)
quaternion = quaternion_from_euler(0, 0, yaw)
self.pos.pose.orientation = Quaternion(*quaternion)
# does it reach the position in 'timeout' seconds?
loop_freq = 2 # Hz
rate = rospy.Rate(loop_freq)
reached = False
for i in xrange(timeout * loop_freq):
if self.is_at_position(self.pos.pose.position.x,
self.pos.pose.position.y,
self.pos.pose.position.z, self.radius):
rospy.loginfo("position reached | seconds: {0} of {1}".format(
i / loop_freq, timeout))
reached = True
break
try:
rate.sleep()
except rospy.ROSException as e:
self.fail(e)
self.assertTrue(reached, (
"took too long to get to position | current position x: {0:.2f}, y: {1:.2f}, z: {2:.2f} | timeout(seconds): {3}".
format(self.local_position.pose.position.x,
self.local_position.pose.position.y,
self.local_position.pose.position.z, timeout)))
#
# Test method
#
def test_posctl(self):
"""Test offboard position control"""
# make sure the simulation is ready to start the mission
self.wait_for_topics(60)
self.wait_for_landed_state(mavutil.mavlink.MAV_LANDED_STATE_ON_GROUND,
10, -1)
self.log_topic_vars()
# exempting failsafe from lost RC to allow offboard
rcl_except = ParamValue(1<<2, 0.0)
self.set_param("COM_RCL_EXCEPT", rcl_except, 5)
self.set_mode("OFFBOARD", 5)
self.set_arm(True, 5)
rospy.loginfo("run mission")
positions = ((0, 0, 0.5), (0, 1, 0.5),(0, -1, 0.5),(0, 1, 0.5),(0, 0, 0.5))
for i in xrange(len(positions)):
self.reach_position(positions[i][0], positions[i][1],
positions[i][2], 30)
rospy.loginfo("Holding Mission for 5 sec.")
rospy.sleep(5.)
rospy.loginfo("Resuming Mission")
self.set_mode("AUTO.LAND", 5)
self.wait_for_landed_state(mavutil.mavlink.MAV_LANDED_STATE_ON_GROUND,
45, 0)
self.set_arm(False, 5)
if __name__ == '__main__':
import rostest
rospy.init_node('test_node', anonymous=True)
rostest.rosrun(PKG, 'mavros_offboard_posctl_test',
MavrosOffboardPosctlTest)