话题订阅者发布者的应用，语音控制机器人

上篇介绍了ros里如何编写话题订阅者和发布者，本篇来做一个简单的应用，语音控制机器人行动。

视频展示地址：http://blog.jiutucao.com:9000/upload/2018/07/speech_move.mp4

在写代码之前需要电脑里配置pocketsphinx，这是一个开源的离线语音识别包，配置的方法自行百度，需要自己训练字库，建议字库不要太复杂，毕竟中国人说英文不是那么标准，太复杂的字库识别率太低。

程序思路很简单：

  Pocketsphinx识别出语音后，会将识别出的语音发布到/Rog_result话题上，我们只需要订阅/Rog_result的消息，对数据做个判断，然后在回调函数里对速度数据进行处理，最后发布到控制速度的/cmd_vel话题上。由于训练的字库并不复杂，Pocketsphinx只能识别出字库里的内容，所以判断也并不复杂。

代码：speech_teleop.cpp

#include \"ros/ros.h\"

#include \"std_msgs/String.h\"

#include <geometry_msgs/Twist.h>

#include <string>

#include <iostream>

using namespace std;

class voicespeech{

       public:

       float line;

       float angle;

       ros::Subscriber sub;

       voicespeech(ros::NodeHandle n);  

       void speechvoiceCallback(const std_msgs::String::ConstPtr& msg);

       void move();

       void stop();

       void fast();

       void slow();

       void left();

       void right();

};

voicespeech::voicespeech(ros::NodeHandle n){

       line = 0.2;

       angle = 0;

       sub = n.subscribe<std_msgs::String>(\"/Rog_result\",10,&voicespeech::speechvoiceCallback,this);

}

void voicespeech::speechvoiceCallback(const std_msgs::String::ConstPtr& msg){

       ROS_INFO(msg->data.c_str());

       std::string command = msg->data;

       if(command.compare(\"启动\") == 0){

              move();

       }else if(command.compare(\"停止\") == 0){

              stop();

       }else if(command.compare(\"加速\") == 0){

              fast();

       }else if(command.compare(\"减速\") == 0){

              slow();

       }else if(command.compare(\"左转\") == 0){

              left();

       }else if(command.compare(\"右转\") == 0){

              right();

       }else{

              ROS_INFO(\"no command\");

       }

}

void voicespeech::move(){

       line = 0.2;

       angle = 0;

}

void voicespeech::stop(){

       line = 0;

       angle = 0;

}

void voicespeech::fast(){

       line = line + 0.1;

       angle = 0;

}

void voicespeech::slow(){

       line = line - 0.1;

       angle = 0;

}

void voicespeech::left(){

       angle = angle + 0.1;

}

void voicespeech::right(){

       //line = 0.2;

       angle = angle - 0.1;

}

int main(int argc, char** argv){

       ros::init(argc , argv ,\"voice_speech\");

       ros::NodeHandle n;

       voicespeech vs(n);

       ros::Publisher pub = n.advertise<geometry_msgs::Twist>(\"cmd_vel\",1);

       ros::Rate loop_rate(10);

       while(ros::ok()){

              geometry_msgs::Twist twist;

              twist.linear.x = vs.line;

           twist.angular.z = vs.angle;

        pub.publish(twist);

              ros::spinOnce();

              loop_rate.sleep();

       }

       ros::spin();

       return 0;

}

Cmakelist.txt

添加如下代码：

set(NODE_MOVE_TEST

       src/move_test/speech_teleop.cpp

)

add_executable(speech_teleop ${NODE_MOVE_TEST} )

target_ _libraries(speech_teleop openrobotComm ${catkin_LIBRARIES})

launch文件

speech_teleop.launch

<launch>

       <node name=\"recognizer\" pkg=\"pocketsphinx\" type=\"recognizer.py\" output=\"screen\">

          <param name=\"lm\" value=\"/home/tt/ppp/src/openrobot/speech_conf/command.lm\"/>

          <param name=\"dict\" value=\"/home/tt/ppp/src/openrobot/speech_conf/command.dic\"/>

        </node>

       <node pkg=\"openrobot\" type=\"speech_teleop\" name=\"speech_teleop\"></node>

</launch>

在launch文件中要指明语音库的路径

运行测试;

连接好设备后，运行launch文件即可