ROS 自动驾驶多点巡航：
1、首先创建工作空间：
基于我们的artca_ws；
2、创建功能包：
进入src目录，输入命令:
catkin_create_pkg point_pkg std_msgs rospy roscpp
test_pkg 为功能包名，后面两个是依赖；
3、创建python文件
我们通过vscode打开src下功能包：
创建 point.py：
代码内容写入 :
#!/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(5.21, -2.07, 0.00), Quaternion(0.000, 0.000, -0.69, 0.72))
locations['point-2'] = Pose(Point(3.50, -5.78, 0.00), Quaternion(0.000, 0.000, 0.99, 0.021))
#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))
# 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(10))
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.")
4、编译：
nano@nano-desktop:~/artcar_ws/src$ cd ..
nano@nano-desktop:~/artcar_ws$ catkin build
5、案例实操；
启动小车并进入到相应环境：
（1）打开终端，启动底盘环境，输入如下命令：
$ roslaunch artcar_nav artcar_bringup.launch
（2）启动导航程序：
$ roslaunch artcar_nav artcar_move_base.launch
（3）启动RVIZ：
（4）获取点位：
rostopic echo /move_base_sile/goal
获取点位
roscar@roscar-virtual-machine:~/artcar_simulation/src$ rostopic echo /move_base_simple/goal
WARNING: no messages received and simulated time is active.
Is /clock being published?
header:
seq: 0
stamp:
secs: 405
nsecs: 141000000
frame_id: "odom"
pose:
position:
x: 5.21420097351
y: -2.07076597214
z: 0.0
orientation:
x: 0.0
y: 0.0
z: -0.69109139328
w: 0.722767380375
---
header:
seq: 1
stamp:
secs: 422
nsecs: 52000000
frame_id: "odom"
pose:
position:
x: 3.50902605057
y: -5.78046607971
z: 0.0
orientation:
x: 0.0
y: 0.0
z: 0.999777096296
w: 0.0211129752124
---
（5）修改point.py文件中点位数据的位置：
(6 ) 然后开启终端执行：
nano@nano-desktop:~/artcar_ws/src/point_pkg/src$ ./point.py
此时确定位置是否准确，准确的话，在此终端中输入：0
小车开始多点运行。
