ROS利用Python脚本实现多点自主导航
本文旨在帮助读者快速实现依次遍历的多点导航，代码地址：GitHub
一、源码解读
#!/usr/bin/env python
import rospy
import actionlib
from actionlib_msgs.msg import *
from geometry_msgs.msg import Pose, PoseWithCovarianceStamped, Point, Quaternion, Twist
from move_base_msgs.msg import MoveBaseAction, MoveBaseGoal
from random import sample
from math import pow, sqrt
class MultiNav():
def __init__(self):
rospy.init_node('MultiNav', anonymous=True)
rospy.on_shutdown(self.shutdown)
# How long in seconds should the robot pause at each location?
self.rest_time = rospy.get_param("~rest_time", 10)
# Are we running in the fake simulator?
self.fake_test = rospy.get_param("~fake_test", False)
# Goal state return values
goal_states = ['PENDING', 'ACTIVE', 'PREEMPTED','SUCCEEDED',
'ABORTED', 'REJECTED','PREEMPTING', 'RECALLING',
'RECALLED','LOST']
# Set up the goal locations. Poses are defined in the map frame.
# An easy way to find the pose coordinates is to point-and-click
# Nav Goals in RViz when running in the simulator.
# Pose coordinates are then displayed in the terminal
# that was used to launch RViz.
locations = dict()
#locations['home_origin'] = Pose(Point(0, 0, 0), Quaternion(0.000, 0.000, 0.000, 0.000))
locations['home_babyroom'] = Pose(Point(0.3, 0.26, 0.00), Quaternion(0.000, 0.000, 0.00, 1.00))
#locations['home_bedroom'] = Pose(Point(3.40, 2.26, 0.00), Quaternion(0.000, 0.000, 0.00143, 0.00143))
locations['home_kitchen'] = Pose(Point(-1.03, 7.28, 0.00), Quaternion(0.000, 0.000, 0.00, 1.00))
locations['home_hall'] = Pose(Point(-1.40, 4.30, 0.00), Quaternion(0.000, 0.000, 0.00, 1.00))
locations['home_sofa'] = Pose(Point(-2.56, 2.82, 0.00), Quaternion(0.000, 0.000, 0.00, 1.00))
locations['home_refrigerator'] = Pose(Point(-1.00, 6.88, 0.00), Quaternion(0.000, 0.000, 0.00, 1.00))
locations['home_door'] = Pose(Point(-2.80, 8.00, 0.00), Quaternion(0.000, 0.000, 0.00143, 1.00))
locations['home_balcony'] = Pose(Point(-2.08, 4.57, 0.00), Quaternion(0.000, 0.000, 0.00143, 1.00))
# Publisher to manually control the robot (e.g. to stop it)
self.cmd_vel_pub = rospy.Publisher('cmd_vel', Twist, queue_size=5)
# Subscribe to the move_base action server
self.move_base = actionlib.SimpleActionClient("move_base", MoveBaseAction)
rospy.loginfo("Waiting for move_base action server...")
# Wait 60 seconds for the action server to become available
self.move_base.wait_for_server(rospy.Duration(60))
rospy.loginfo("Connected to move base server")
# A variable to hold the initial pose of the robot to be set by the user in RViz
initial_pose = PoseWithCovarianceStamped()
# Variables to keep track of success rate, running time, and distance traveled
n_locations = len(locations)
n_goals = 0
n_successes = 0
i = n_locations
distance_traveled = 0
start_time = rospy.Time.now()
running_time = 0
location = ""
last_location = ""
# Get the initial pose from the user
rospy.loginfo("Click on the map in RViz to set the intial pose...")
rospy.wait_for_message('initialpose', PoseWithCovarianceStamped)
self.last_location = Pose()
rospy.Subscriber('initialpose', PoseWithCovarianceStamped, self.update_initial_pose)
# Make sure we have the initial pose
while initial_pose.header.stamp == "":
rospy.sleep(1)
rospy.loginfo("Starting navigation test")
# Begin the main loop and run through a sequence of locations
while not rospy.is_shutdown():
# If we've gone through the current sequence, start with a new random sequence
if i == n_locations:
i = 0
sequence = sample(locations, n_locations)
# Skip over first location if it is the same as the last location
if sequence[0] == last_location:
i = 1
# Get the next location in the current sequence
location = sequence[i]
# Keep track of the distance traveled.
# Use updated initial pose if available.
if initial_pose.header.stamp == "":
distance = sqrt(pow(locations[location].position.x
- locations[last_location].position.x, 2) +
pow(locations[location].position.y -
locations[last_location].position.y, 2))
else:
rospy.loginfo("Updating current pose.")
distance = sqrt(pow(locations[location].position.x
- initial_pose.pose.pose.position.x, 2) +
pow(locations[location].position.y -
initial_pose.pose.pose.position.y, 2))
initial_pose.header.stamp = ""
# Store the last location for distance calculations
last_location = location
# Increment the counters
i += 1
n_goals += 1
# Set up the next goal location
self.goal = MoveBaseGoal()
self.goal.target_pose.pose = locations[location]
self.goal.target_pose.header.frame_id = 'map'
self.goal.target_pose.header.stamp = rospy.Time.now()
# Let the user know where the robot is going next
rospy.loginfo("Going to: " + str(location))
# Start the robot toward the next location
self.move_base.send_goal(self.goal)
# Allow 5 minutes to get there
finished_within_time = self.move_base.wait_for_result(rospy.Duration(300))
# Check for success or failure
if not finished_within_time:
self.move_base.cancel_goal()
rospy.loginfo("Timed out achieving goal")
else:
state = self.move_base.get_state()
if state == GoalStatus.SUCCEEDED:
rospy.loginfo("Goal succeeded!")
n_successes += 1
distance_traveled += distance
else:
rospy.loginfo("Goal failed with error code: " + str(goal_states[state]))
# How long have we been running?
running_time = rospy.Time.now() - start_time
running_time = running_time.secs / 60.0
# Print a summary success/failure, distance traveled and time elapsed
rospy.loginfo("Success so far: " + str(n_successes) + "/" +
str(n_goals) + " = " + str(100 * n_successes/n_goals) + "%")
rospy.loginfo("Running time: " + str(trunc(running_time, 1)) +
" min Distance: " + str(trunc(distance_traveled, 1)) + " m")
rospy.sleep(self.rest_time)
def update_initial_pose(self, initial_pose):
self.initial_pose = initial_pose
def shutdown(self):
rospy.loginfo("Stopping the robot...")
self.move_base.cancel_goal()
rospy.sleep(2)
self.cmd_vel_pub.publish(Twist())
rospy.sleep(1)
def trunc(f, n):
# Truncates/pads a float f to n decimal places without rounding
slen = len('%.*f' % (n, f))
return float(str(f)[:slen])
if __name__ == '__main__':
try:
MultiNav()
rospy.spin()
except rospy.ROSInterruptException:
rospy.loginfo("AMCL navigation test finished.") 源码部分采用无序字典定义多个目标点的位姿，并且使用sample随机取值，无法实现依次到达各目标点。并且在接收到Rviz中2D Pose之后会直接启动导航，没有考虑到初始位姿存在偏差的问题，对其做如下修改。
二、实用修改
#!/usr/bin/env python
import rospy
import actionlib
import collections
from actionlib_msgs.msg import *
from geometry_msgs.msg import Pose, PoseWithCovarianceStamped, Point, Quaternion, Twist
from move_base_msgs.msg import MoveBaseAction, MoveBaseGoal
from random import sample
from math import pow, sqrt
class MultiNav():
def __init__(self):
rospy.init_node('MultiNav', anonymous=True)
rospy.on_shutdown(self.shutdown)
# How long in seconds should the robot pause at each location?
self.rest_time = rospy.get_param("~rest_time", 10)
# Are we running in the fake simulator?
self.fake_test = rospy.get_param("~fake_test", False)
# Goal state return values
goal_states = ['PENDING', 'ACTIVE', 'PREEMPTED','SUCCEEDED',
'ABORTED', 'REJECTED','PREEMPTING', 'RECALLING',
'RECALLED','LOST']
# Set up the goal locations. Poses are defined in the map frame.
# An easy way to find the pose coordinates is to point-and-click
# Nav Goals in RViz when running in the simulator.
# Pose coordinates are then displayed in the terminal
# that was used to launch RViz.
locations = collections.OrderedDict()
locations['point-1'] = Pose(Point(-9.28, 2.57, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-2'] = Pose(Point(-7.85, 2.16, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-3'] = Pose(Point(-6.95, 2.26, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-4'] = Pose(Point(-6.50, 2.04, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-5'] = Pose(Point(-5.90, 1.72, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-6'] = Pose(Point(-5.28, 0.88, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-7'] = Pose(Point(-4.47, 0.90, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-8'] = Pose(Point(-3.81, 0.64, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-9'] = Pose(Point(-3.51, 0.44, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-10'] = Pose(Point(-2.70, 0.11, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-11'] = Pose(Point(-2.11, 0.08, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-12'] = Pose(Point(-1.44, 0.18, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-13'] = Pose(Point(-0.49, -0.43, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
locations['point-14'] = Pose(Point(0.20, -1.61, 0.00), Quaternion(0.000, 0.000, 0.000, 1.000))
# Publisher to manually control the robot (e.g. to stop it)
self.cmd_vel_pub = rospy.Publisher('cmd_vel', Twist, queue_size=5)
# Subscribe to the move_base action server
self.move_base = actionlib.SimpleActionClient("move_base", MoveBaseAction)
rospy.loginfo("Waiting for move_base action server...")
# Wait 60 seconds for the action server to become available
self.move_base.wait_for_server(rospy.Duration(60))
rospy.loginfo("Connected to move base server")
# A variable to hold the initial pose of the robot to be set by the user in RViz
initial_pose = PoseWithCovarianceStamped()
# Variables to keep track of success rate, running time, and distance traveled
n_locations = len(locations)
n_goals = 0
n_successes = 0
i = 0
distance_traveled = 0
start_time = rospy.Time.now()
running_time = 0
location = ""
last_location = ""
# Get the initial pose from the user
rospy.loginfo("Click on the map in RViz to set the intial pose...")
rospy.wait_for_message('initialpose', PoseWithCovarianceStamped)
self.last_location = Pose()
rospy.Subscriber('initialpose', PoseWithCovarianceStamped, self.update_initial_pose)
keyinput = int(input("Input 0 to continue,or reget the initialpose!\n"))
while keyinput != 0:
rospy.loginfo("Click on the map in RViz to set the intial pose...")
rospy.wait_for_message('initialpose', PoseWithCovarianceStamped)
rospy.Subscriber('initialpose', PoseWithCovarianceStamped, self.update_initial_pose)
rospy.loginfo("Press y to continue,or reget the initialpose!")
keyinput = int(input("Input 0 to continue,or reget the initialpose!"))
# Make sure we have the initial pose
while initial_pose.header.stamp == "":
rospy.sleep(1)
rospy.loginfo("Starting navigation test")
# Begin the main loop and run through a sequence of locations
for location in locations.keys():
rospy.loginfo("Updating current pose.")
distance = sqrt(pow(locations[location].position.x
- initial_pose.pose.pose.position.x, 2) +
pow(locations[location].position.y -
initial_pose.pose.pose.position.y, 2))
initial_pose.header.stamp = ""
# Store the last location for distance calculations
last_location = location
# Increment the counters
i += 1
n_goals += 1
# Set up the next goal location
self.goal = MoveBaseGoal()
self.goal.target_pose.pose = locations[location]
self.goal.target_pose.header.frame_id = 'map'
self.goal.target_pose.header.stamp = rospy.Time.now()
# Let the user know where the robot is going next
rospy.loginfo("Going to: " + str(location))
# Start the robot toward the next location
self.move_base.send_goal(self.goal)
# Allow 5 minutes to get there
finished_within_time = self.move_base.wait_for_result(rospy.Duration(300))
# Check for success or failure
if not finished_within_time:
self.move_base.cancel_goal()
rospy.loginfo("Timed out achieving goal")
else:
state = self.move_base.get_state()
if state == GoalStatus.SUCCEEDED:
rospy.loginfo("Goal succeeded!")
n_successes += 1
distance_traveled += distance
else:
rospy.loginfo("Goal failed with error code: " + str(goal_states[state]))
# How long have we been running?
running_time = rospy.Time.now() - start_time
running_time = running_time.secs / 60.0
# Print a summary success/failure, distance traveled and time elapsed
rospy.loginfo("Success so far: " + str(n_successes) + "/" +
str(n_goals) + " = " + str(100 * n_successes/n_goals) + "%")
rospy.loginfo("Running time: " + str(trunc(running_time, 1)) +
" min Distance: " + str(trunc(distance_traveled, 1)) + " m")
rospy.sleep(self.rest_time)
def update_initial_pose(self, initial_pose):
self.initial_pose = initial_pose
def shutdown(self):
rospy.loginfo("Stopping the robot...")
self.move_base.cancel_goal()
rospy.sleep(2)
self.cmd_vel_pub.publish(Twist())
rospy.sleep(1)
def trunc(f, n):
# Truncates/pads a float f to n decimal places without rounding
slen = len('%.*f' % (n, f))
return float(str(f)[:slen])
if __name__ == '__main__':
try:
MultiNav()
rospy.spin()
except rospy.ROSInterruptException:
rospy.loginfo("AMCL navigation test finished.") 修改后的代码采用有序字典，可以实现多目标点依次导航；在此基础上，为防止出现初始位姿偏差较大但仍开始导航的问题，在代码中加入了：
keyinput = int(input("Input 0 to continue,or reget the initialpose!\n"))
while keyinput != 0:
rospy.loginfo("Click on the map in RViz to set the intial pose...")
rospy.wait_for_message('initialpose', PoseWithCovarianceStamped)
rospy.Subscriber('initialpose', PoseWithCovarianceStamped, self.update_initial_pose)
rospy.loginfo("Press y to continue,or reget the initialpose!")
keyinput = int(input("Input 0 to continue,or reget the initialpose!"))在初始化后，如果对初始结果不满意，可以在终端中输入任意非0符，重新初始化，如此反复直到初始位姿较为准确后，终端中输入‘0’开始导航！