ROS机器人从起点到终点（一）简单P控制

这部分可以参考之前案例：

☞ ​​ROS编程（ETH）2018更新版习题说明（三）_zhangrelay的博客​​

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遥控肯定没难度，但是精度也很差哦。

 

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获取目标位置与当前位置之间的误差，用于机器人运动控制。

假定目标x=10.0 y=1.5，求解机器人控制速度？ 

获取位置：

#include <ros/ros.h>
#include "turtlesim/Pose.h"

void poseCallback(const turtlesim::Pose::ConstPtr& msg)
{
    ROS_INFO("Turtle pose: x:%0.6f, y:%0.6f", msg->x, msg->y);
}

int main(int argc, char **argv)
{
    ros::init(argc, argv, "pose_subscriber");

    ros::NodeHandle n;

    ros::Subscriber pose_sub = n.subscribe("/turtle1/pose", 10, poseCallback);

    ros::spin();

    return 0;
}

发布速度：

#include <ros/ros.h>
#include <geometry_msgs/Twist.h>

int main(int argc, char **argv)
{
  ros::init(argc, argv, "velocity_publisher");

  ros::NodeHandle n;

  ros::Publisher turtle_vel_pub = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 10);

  ros::Rate loop_rate(10);

  int count = 0;
  while (ros::ok())
  {
    geometry_msgs::Twist vel_msg;
    vel_msg.linear.x = 0.5;
    vel_msg.angular.z = 0.2;

    turtle_vel_pub.publish(vel_msg);
    ROS_INFO("Publsh turtle velocity command[%0.2f m/s, %0.2f rad/s]", 
        vel_msg.linear.x, vel_msg.angular.z);

      loop_rate.sleep();
  }

  return 0;
}

暴力揉到一起…………………………不推荐……………………

 

 

 

#include <ros/ros.h>
#include <geometry_msgs/Twist.h>
#include "turtlesim/Pose.h"

float goal_x=10.0,goal_y=1.5,vel_x=0,vel_z=0;

void poseCallback(const turtlesim::Pose::ConstPtr& msg)
{
    ROS_INFO("Turtle pose: x:%0.6f, y:%0.6f", msg->x, msg->y);
    vel_x=(goal_x-msg->x)/8.0;
    vel_z=(goal_y-msg->y)/40.0;
}

int main(int argc, char **argv)
{
    ros::init(argc, argv, "pose_sub_vel_pub");

    ros::NodeHandle n;

    ros::Subscriber pose_sub = n.subscribe("/turtle1/pose", 10, poseCallback);

    ros::Publisher turtle_vel_pub = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 10);
    
    ros::Rate loop_rate(10);

    int count = 0;
    geometry_msgs::Twist vel_msg;
    vel_msg.linear.x = 0.0;
    vel_msg.angular.z = 0.0;


    while (ros::ok())
    {
    vel_msg.linear.x=vel_x;
    vel_msg.angular.z=vel_z;
    turtle_vel_pub.publish(vel_msg);
    ROS_INFO("Publsh turtle velocity command[%0.2f m/s, %0.2f rad/s]", 
                vel_msg.linear.x, vel_msg.angular.z);
        ros::spinOnce();    
    loop_rate.sleep();
    }

    return 0;
}

更好用的代码需要自己研究哦 。

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