SimpleActionClient端(Python)

SimpleActionClient创建流程

1. 创建Node节点

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rospy.init_node(nodeName, anonymous=True)

2. 创建SimpleActionClient

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client = actionlib.SimpleActionClient(actionName, CountNumberAction)
client.wait_for_server()

Tip

我们需要引入actionlib这个依赖库，添加模块导入

import actionlib

actionlib.SimpleActionClient： Action的Client端对应的类。

第一个参数：当前action的名称

第二个参数：当前action的消息类型

3. 发送Goal指令给Server端

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goal = CountNumberGoal(max=100, duration=0.5)
client.send_goal(goal, done_cb=done_cb, active_cb=active_cb, feedback_cb=feedback_cb)

Tip

def send_goal(self, goal, done_cb=None, active_cb=None, feedback_cb=None)

send_goal函数，对应了几个参数。

第一个参数goal： 对应的是发送的指令数据，server端会根据客户端的数据进行对应的逻辑。

第二个参数done_cb：server端完成耗时操作时，告知客户端的回调。

第三个参数active_cb: server端在执行操作过程中，告知客户端的开始执行任务的回调。

第四个参数feedback_cb: server端在执行操作过程中，告知客户端的进度回调。

4.完成回调

结果回调

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def done_cb(state, result):
    rospy.loginfo(state)
    rospy.loginfo(result)

    if state == GoalStatus.ABORTED:
        rospy.loginfo("server working error, don't finish my job.")
    elif state == GoalStatus.PREEMPTED:
        rospy.loginfo("client cancel job.")
    elif state == state.SUCCEEDED:
        rospy.loginfo("server finish job.")
        rospy.loginfo("result: %f" % result.count)

开始回调

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def active_cb():
    rospy.loginfo("active callback")

进度回调

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def feedback_cb(feedback):
    rospy.loginfo(feedback)

完整代码

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#!/usr/bin/env python
# coding:utf-8

import rospy
import actionlib
from actionlib import GoalStatus
from demo_actions.msg import CountNumberAction, CountNumberGoal, CountNumberResult


def done_cb(state, result):
    rospy.loginfo(state)
    rospy.loginfo(result)

    if state == GoalStatus.ABORTED:
        rospy.loginfo("server working error, don't finish my job.")
    elif state == GoalStatus.PREEMPTED:
        rospy.loginfo("client cancel job.")
    elif state == state.SUCCEEDED:
        rospy.loginfo("server finish job.")
        rospy.loginfo("result: %f" % result.count)


def active_cb():
    rospy.loginfo("active callback")


def feedback_cb(feedback):
    rospy.loginfo(feedback)


if __name__ == '__main__':
    nodeName = "CountNumberClint"
    actionName = "/count_number"

    # 创建节点
    rospy.init_node(nodeName, anonymous=True)

    # 创建客户端
    client = actionlib.SimpleActionClient(actionName, CountNumberAction)

    # 等待连接服务器
    client.wait_for_server()

    # 发送请求
    goal = CountNumberGoal(max=100, duration=0.5)
    client.send_goal(goal, done_cb=done_cb, feedback_cb=feedback_cb)

    rospy.spin()

调试Client端

通过现有的server端进行调试。