1 #命令
 2 rosservice list         print information about active services
 3 rosservice call         call the service with the provided args
 4 rosservice type         print service type
 5 rosservice find         find services by service type
 6 rosservice uri          print service ROSRPC uri
 7 #例子
 8 rosservice list
 9 /clear
10 /kill
11 /reset
12 /rosout/get_loggers
13 /rosout/set_logger_level
14 /spawn
15 /teleop_turtle/get_loggers
16 /teleop_turtle/set_logger_level
17 /turtle1/set_pen
18 /turtle1/teleport_absolute
19 /turtle1/teleport_relative
20 /turtlesim/get_loggers
21 /turtlesim/set_logger_level
22 #另一个例子
23 rosservice type [service]
24
25 rosservice type /clear  #你会发现这个命令是没有什么东西，

1 当你运行着一条的
2 $ rosservice call /clear
3 就可以清空小乌龟的轨迹哦。
4 运行着一条的时候
5 rosservice call /spawn 2 2 0.2 ""
6 你会发现另一只小乌龟出现啦！

1 rosparam set [param_name]  #设置参数
2 rosparam get [param_name]  #得到参数
3 rosparam set /background_r 150  #把参数设置成150
4 rosparam get /background_g  #获得G的参数
5 rosparam get /  #获得所有参数

1 rosparam dump [file_name] [namespace]  #将参数写进 。yaml文件中
2 rosparam load [file_name] [namespace]
3
4 rosparam dump params.yaml
5
6 rosparam load params.yaml copy
7  rosparam get /copy/background_b

1 rosrun rqt_console rqt_console
2 rosrun rqt_logger_level rqt_logger_level
3
4 http://wiki.ros.org/ROS/Tutorials/UsingRqtconsoleRoslaunch#CA-21ef414cf4c910bb1286ff2aedfe349a32a099b9_1

 1 cd ~/catkin_ws2  source devel/setup.bash3  roscd beginner_tutorials4 mkdir launch5  cd launch6 touch turtlemimic.launch 7 vi turtlemimic.launch 8 9 文件内容
10 <launch>                 #嘛 告诉你这是个lanunch 文件
11
12   <group ns="turtlesim1">
13     <node pkg="turtlesim" name="sim" type="turtlesim_node"/>   #嘛 定义以下这个节点的名字呀，sim ，类型呀。
14   </group>
15
16   <group ns="turtlesim2">                                      #第二个节点
17     <node pkg="turtlesim" name="sim" type="turtlesim_node"/>
18   </group>
19
20   <node pkg="turtlesim" name="mimic" type="mimic">           #第三个节点，命令文件，可以让小乌龟跑哦。
21     <remap from="input" to="turtlesim1/turtle1"/>
22     <remap from="output" to= 　　"turtlesim2/turtle1"/>           # 运行之后，你能想想到，节点之间是怎么  传递 订阅消息哦的吗？
23   </node>
24
25 </launch>

这样你运行  roslaunch beginner_tutorials turtlemimic.launch  你就会发现两只小乌龟出现啦！

然后你发不一条命令 rostopic pub /turtlesim1/turtle1/cmd_vel geometry_msgs/Twist -r 1 -- '[2.0, 0.0, 0.0]' '[0.0, 0.0, -1.8]'   两只小乌龟就可以动啦!

$ roscd beginner_tutorials
$ mkdir msg
$ echo "int64 num" > msg/Num.msg   #以上是创建msg 并且将int64 写入，也可以用其他方式写  in package.xlm   make sure      #以下是告诉package，xml 以及 camke 我们要创建msg <build_depend>message_generation</build_depend><run_depend>message_runtime</run_depend>
in CMakeLists.txt  make sure
find_package(catkin REQUIRED COMPONENTSroscpprospystd_msgsmessage_generation
)
catkin_package(...CATKIN_DEPENDS message_runtime ......)
add_message_files(FILESNum.msg
)
generate_messages(DEPENDENCIESstd_msgs
)

查看一个信息。。rosmsg show XX

 1 #!/usr/bin/env python
 2 # license removed for brevity
 3 import rospy
 4 from std_msgs.msg import String
 5
 6 def talker():
 7     pub = rospy.Publisher('chatter', String, queue_size=10) #节点发送了chatter topic 以 msg type string 的形式
 8     rospy.init_node('talker', anonymous=True) # rospy.init_node(NAME)  是非常重要的，告诉了rospy 节点的名字，这样roscore 才可以管理
 9     rate = rospy.Rate(10) # 10hz 一中非常好的方法，可以循环。因为是没有 十分之一秒的/
10     while not rospy.is_shutdown():
11         hello_str = "hello world %s" % rospy.get_time()
12         rospy.loginfo(hello_str)
13         pub.publish(hello_str)
14         rate.sleep()          #这段loop 是为你没有crlt+c 的时候，你可以一直保持稳定的运行。
15
16 if __name__ == '__main__':　　
17     try:
18         talker()
19     except rospy.ROSInterruptException:
20         pass

#!/usr/bin/env python
import rospy
from std_msgs.msg import Stringdef callback(data):rospy.loginfo(rospy.get_caller_id() + "I heard %s", data.data)def listener():# In ROS, nodes are uniquely named. If two nodes with the same# node are launched, the previous one is kicked off. The# anonymous=True flag means that rospy will choose a unique# name for our 'listener' node so that multiple listeners can# run simultaneously.rospy.init_node('listener', anonymous=True)rospy.Subscriber("chatter", String, callback)# spin() simply keeps python from exiting until this node is stopped
    rospy.spin()if __name__ == '__main__':listener()

 1 # Create the scripts/add_two_ints_server.py file within the beginner_tutorials package and paste the following inside it:
 2
 3 #!/usr/bin/env python
 4
 5 from beginner_tutorials.srv import *
 6 import rospy
 7
 8 def handle_add_two_ints(req):
 9     print "Returning [%s + %s = %s]"%(req.a, req.b, (req.a + req.b))
10     return AddTwoIntsResponse(req.a + req.b)   #表示加法的
11 #实现发布 service
12 def add_two_ints_server():
13     rospy.init_node('add_two_ints_server')
14     s = rospy.Service('add_two_ints', AddTwoInts, handle_add_two_ints)
15     print "Ready to add two ints."
16     rospy.spin()    # 确保在没有结束这段程序之前，他就一直运行。
17
18 if __name__ == "__main__":
19     add_two_ints_server()

 1 #!/usr/bin/env python
 2
 3 import sys
 4 import rospy
 5 from beginner_tutorials.srv import *
 6
 7 def add_two_ints_client(x, y):
 8     rospy.wait_for_service('add_two_ints')  #等待 服务。
 9     try:
10         add_two_ints = rospy.ServiceProxy('add_two_ints', AddTwoInts)
11         resp1 = add_two_ints(x, y)
12         return resp1.sum
13     except rospy.ServiceException, e:
14         print "Service call failed: %s"%e
15
16 def usage():
17     return "%s [x y]"%sys.argv[0]
18
19 if __name__ == "__main__":
20     if len(sys.argv) == 3:
21         x = int(sys.argv[1])
22         y = int(sys.argv[2])
23     else:
24         print usage()
25         sys.exit(1)
26     print "Requesting %s+%s"%(x, y)
27     print "%s + %s = %s"%(x, y, add_two_ints_client(x, y))