一、创建ros软件包

bash 复制代码

#1、创建工作空间
mkdir 2d_robot_ws
cd 2d_robot_ws
mkdir src
cd src
catkin_init_workspace
#2、编译工作空间
cd ..
catkin_make
#3、创建软件包
catkin_create_pkg 2d_robot std_msgs rospy roscpp

二、创建模型文件

1、编写urdf模型文件

在2d_robot_ws/src/2d_robot下创建launch文件夹和urdf文件夹，launch文件夹中放启动文件，urdf文件夹中放模型文件。

2d_robot_model.urdf

xml 复制代码

<?xml version="1.0"?>
<robot name="my_robot">

    <link name="link_base">            基座机构
        <inertial>
            <origin  xyz="0 0 0" rpy="0 0 0"/>
            <mass value="10"/>
            <inertia ixx="100" ixy="0" ixz="0" iyy="100" izz="100" iyz="0"/>
        </inertial>
        
        <visual>
            <origin xyz="0.0 0.0 0.0" rpy="0.0 0.0 0.0"/>    
            <geometry>
                <box size="5.0 5.0 1.0"/>
            </geometry>
            <material name="123">
                <color rgba="0.0 1.0 1.0 1.0"/>
            </material>
        </visual>

        <collision>
            <origin xyz="0.0 0.0 0.0" rpy="0.0 0.0 0.0"/>
            <geometry>
                <box size="5.0 5.0 1.0"/>
            </geometry>
        </collision>

    </link>


   <link name="link_one">         第二个机构
        <inertial>
            <origin  xyz="0.0 0.0 5.0" rpy="0.0 0.0 0.0"/>
            <mass value="5"/>
            <inertia ixx="100" ixy="0" ixz="0" iyy="100" izz="100" iyz="0"/>
        </inertial>
        
        <visual>
            <origin xyz="0.0 0.0 5.0" rpy="0.0 0.0 0.0"/>    
            <geometry>
                <box size="3.0 3.0 10.0"/>
            </geometry>
            <material name="234">
                <color rgba="0.8 0.5 0 0.5"/>
            </material>
        </visual>

        <collision>
            <origin xyz="0.0 0.0 5.0" rpy="0.0 0.0 0.0"/>
            <geometry>
                <box size="1.0 1.0 10.0"/>
            </geometry>
        </collision>
        
    </link>


   <link name="link_two">            第二个机构
        <inertial>
            <origin  xyz="0.0 0.0 5.0" rpy="0.0 0.0 0.0"/>
            <mass value="5"/>
            <inertia ixx="100" ixy="0" ixz="0" iyy="100" izz="100" iyz="0"/>
        </inertial>
        
        <visual>
            <origin xyz="0.0 0.0 5.0" rpy="0.0 0.0 0.0"/>    
            <geometry>
                <box size="1.0 1.0 10.0"/>
            </geometry>
            <material name="234">
                <color rgba="0.0 5.0 1.0 1.0"/>
            </material>
        </visual>

        <collision>
            <origin xyz="0.0 0.0 5.0" rpy="0.0 0.0 0.0"/>
            <geometry>
                <box size="1.0 1.0 10.0"/>
            </geometry>
        </collision>
        
    </link>


    <joint name="joint_one" type="revolute">           第一个关节，连接基座和机构1
        <origin xyz="0.0 0.0 0.0" rpy="0.0 0.0 0.0"/>
        <parent link="link_base"/>
        <child link="link_one"/>
        <axis xyz="1.0 0.0 0.0"/>
        <limit lower="-3.0" upper="3.0" effort="10.0" velocity="3.0"/>
    </joint>


    <joint name="joint_two" type="revolute">            第二个关节，连接机构1和机构2
        <origin xyz="0.0 0.0 10.0" rpy="0.0 0.0 0.0"/>
        <parent link="link_one"/>
        <child link="link_two"/>
        <axis xyz="1.0 0.0 0.0"/>
        <limit lower="-3.0" upper="3.0" effort="10.0" velocity="3.0"/>
    </joint>

</robot>

2、用rviz查看urdf模型

2d_robot_rviz.launch

xml 复制代码

<?xml version="1.0"?>
<launch>
    <arg name="model" />
    <!-- 加载机器人模型参数 -->
    <param name="robot_description" textfile="/media/wangyuanhao/DATA/ros_data/2d_robot_ws/src/2d_robot/urdf/2d_robot_model.urdf" />
 
    <!-- 设置GUI参数，显示关节控制插件 -->
    <param name="use_gui" value="true"/>
 
    <!-- 运行joint_state_publisher节点，发布机器人的关节状态  -->
    <node name="joint_state_publisher" pkg="joint_state_publisher" type="joint_state_publisher" />
    
    <!-- 运行robot_state_publisher节点，发布tf  -->
    <node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher" />
 
    <!-- 运行rviz可视化界面 -->
    <node name="rviz" pkg="rviz" type="rviz" args="-d $(find urdf_tutorial)/urdf.rviz" />
</launch>

roslaunch命令

bash 复制代码

roslaunch 2d_robot 2d_robot_rviz.launch

启动rviz后添加机器人类型，并设置fixed frame

3、urdf转sdf

bash 复制代码

gz sdf -p 2d_robot_model.urdf > 2d_robot_model.sdf

三、gazebo仿真

1、编写模型文件

要让sdf模型文件可以在world文件中引用需要sdf和config两个文件，新建一个文件夹命名为2d_robot，其中分别有model.sdf和model.config文件。

model.sdf就是一般的sdf文件，config文件如下：
model.config

xml 复制代码

<?xml version="1.0"?>
<model>
  <name>My Robot</name>
  <version>1.0</version>
  <sdf version='1.4'>model.sdf</sdf>

  <author>
   <name>My Name</name>
   <email>me@my.email</email>
  </author>

  <description>
    My awesome robot.
  </description>
</model>

2、编写world文件（导入sdf模型）

2d_robot.world

xml 复制代码

<?xml version="1.0" ?>
<sdf version="1.4">
  <world name="default">
    <include>
      <uri>model://ground_plane</uri>
    </include>
    <include>
      <uri>model://sun</uri>
    </include>
    <include>
      <scale>1 1 1</scale>      
      <uri>///media/wangyuanhao/DATA/ros_data/2d_robot_ws/src/2d_robot/sdf/2d_robot</uri>
      <name>2d_robot</name>
      <pose>-2.0 7.0 0 0 0 0</pose>
    </include>
  </world>
</sdf>

2、将world文件导入gazebo（空白世界+world文件）

2d_robot_gazebo.launch

xml 复制代码

<launch>
  <!-- We resume the logic in empty_world.launch, changing only the name of the world to be launched -->
  <include file="$(find gazebo_ros)/launch/empty_world.launch">
    <arg name="world_name" value="$(find 2d_robot)/worlds/2d_robot.world"/>
    <!-- more default parameters can be changed here -->
  </include>
</launch>

roslaunch启动命令

bash 复制代码

roslaunch 2d_robot 2d_robot_gazebo.launch

3、world文件中加入gazebo插件

3.1添加世界插件hello_world

3.1.1编写插件

hello_world.cc

cpp 复制代码

#include <gazebo/gazebo.hh>

namespace gazebo
{
  class WorldPluginTutorial : public WorldPlugin
  {
    public: WorldPluginTutorial() : WorldPlugin()
            {
              printf("Hello World!\n");
            }

    public: void Load(physics::WorldPtr _world, sdf::ElementPtr _sdf)
            {
            }
  };
  GZ_REGISTER_WORLD_PLUGIN(WorldPluginTutorial)
}

3.1.2编译插件

CMakeLists.txt

xml 复制代码

cmake_minimum_required(VERSION 2.8 FATAL_ERROR)

find_package(gazebo REQUIRED)
include_directories(${GAZEBO_INCLUDE_DIRS})
link_directories(${GAZEBO_LIBRARY_DIRS})
list(APPEND CMAKE_CXX_FLAGS "${GAZEBO_CXX_FLAGS}")

add_library(hello_world SHARED hello_world.cc)
target_link_libraries(hello_world ${GAZEBO_LIBRARIES})

这里要注意一下不能使用boost1.69以上的库，所以要确认自己的版本。

添加so文件路径

我这里是把so文件放到了gazebo的插件路经的文件夹中，我电脑的路径是/usr/lib/x86_64-linux-gnu/gazebo-9/plugins。

3.1.3在world中引用

2d_robot.world

xml 复制代码

<?xml version="1.0" ?>
<sdf version="1.4">
  <world name="default">
  <plugin name="hello_world" filename="libhello_world.so"/>
    <include>
      <uri>model://ground_plane</uri>
    </include>
    <include>
      <uri>model://sun</uri>
    </include>
    <include>
      <scale>1 1 1</scale>      
      <uri>///media/wangyuanhao/DATA/ros_data/2d_robot_ws/src/2d_robot/sdf/2d_robot</uri>
      <name>2d_robot</name>
      <pose>-2.0 7.0 0 0 0 0</pose>
    </include>
  </world>
</sdf>

最终效果：

3.2添加模型插件pos_update

https://blog.csdn.net/Robot_Starscream/article/details/120323907

https://zhuanlan.zhihu.com/p/363385163

3.2.1编写插件

这里主要就是借鉴了第一个链接里面的代码，只是可能因为版本不同，get_angle的函数没有了换成了GetForce。
back_wheel_steering.hh

cpp 复制代码

#ifndef _BACK_WHEEL_ROLLINGANGLE_HH_
#define _BACK_WHEEL_ROLLINGANGLE_HH_
 
#include <boost/thread.hpp>
#include <cmath>
#include <fstream>
#include <iostream>
#include <string>
#include <thread>
 
// gazebo
#include <gazebo/gazebo.hh>
#include <gazebo/physics/physics.hh>
 
#include <gazebo/gazebo_client.hh>
#include <gazebo/msgs/msgs.hh>
#include <gazebo/transport/transport.hh>
 
#include "std_msgs/Float64.h"
#include "ros/callback_queue.h"
#include "ros/ros.h"
#include "ros/subscribe_options.h"
#include "ros/subscription_callback_helper.h"
 
namespace gazebo{
	class back_wheel_steering : public ModelPlugin{
        public:
                virtual ~back_wheel_steering();
                back_wheel_steering();
                void virtual Load(physics::ModelPtr _model, sdf::ElementPtr _sdf);
                void OnUpdate();
                double B_wheel_steering;
 
        private:
                physics::ModelPtr model;
                physics::JointPtr prismaticJoint;
                event::ConnectionPtr BWP_updateConnection;
                ros::NodeHandle P_joint_steering_Node;
                ros::Publisher rosPub_P_joint_steering;
                std::string P_joint_steering_PubTopic;
                std_msgs::Float64 B_wheel_steering_msg;
 
                int SimulateCount=0;
                int PrintStep=1000;
    };
        
}
#endif

back_wheel_steering.cc

cpp 复制代码

#include "back_wheel_steering.hh"
#define IS_DEBUG 0
namespace gazebo
{
    back_wheel_steering::back_wheel_steering(){
        std::cout << "start1" << std::endl;
        std::cout << "start2" << std::endl;
    }
    back_wheel_steering::~back_wheel_steering(){}
     
    void back_wheel_steering::Load(physics::ModelPtr _model, sdf::ElementPtr _sdf){
        // Just output a message for now 
        //std::cerr << "\nThe velodyne plugin is attach to model[" << _model->GetName() << "]\n";
        std::cout << "go in Load" << std::endl; 
        this->model = _model;
        this->prismaticJoint = this->model->GetJoint(_sdf->GetElement("prismaticJoint")->Get<std::string>());   //_sdf是插件标签的指针，等于说获取了插件的参数
        this->P_joint_steering_PubTopic = _sdf->GetElement("P_joint_position_Topic")->Get<std::string>();
 
        rosPub_P_joint_steering = this->P_joint_steering_Node.advertise<std_msgs::Float64>(P_joint_steering_PubTopic, 10);
        this->BWP_updateConnection = event::Events::ConnectWorldUpdateBegin(
            std::bind(&back_wheel_steering::OnUpdate, this));
    }
 
    void back_wheel_steering::OnUpdate(){
        B_wheel_steering = this->prismaticJoint->GetForce(0);
        B_wheel_steering_msg.data = B_wheel_steering;
        rosPub_P_joint_steering.publish(B_wheel_steering_msg);
        SimulateCount++;
    //    std::cout << "++++++++++++++++++++++++++++++++" << std::endl;
        if ((SimulateCount % PrintStep == 0)){
            std::cout << "++++++++++++++++++++++++++++++++" << std::endl;
            std::cout<< "back_wheel_steeringangle：" << B_wheel_steering<<std::endl;
            std::cout << "++++++++++++++++++++++++++++++++" << std::endl;
        }
    }
    
GZ_REGISTER_MODEL_PLUGIN(back_wheel_steering)
}

3.2.2编译插件

因为代码中使用了ros的msg，所以引入了ros的一些依赖。
CMakeLists.txt

xml 复制代码

cmake_minimum_required(VERSION 3.0.2)
project(gazebo_joint_plug_pkg)
find_package(catkin REQUIRED COMPONENTS
  roscpp
  rospy
  std_msgs
)
include_directories(
# include
  ${catkin_INCLUDE_DIRS}
)
find_package(gazebo REQUIRED)
include_directories(${GAZEBO_INCLUDE_DIRS})
link_directories(${GAZEBO_LIBRARY_DIRS})
list(APPEND CMAKE_CXX_FLAGS "${GAZEBO_CXX_FLAGS}")

add_library(joint_plug SHARED src/back_wheel_steering.cc)
target_link_libraries(joint_plug ${GAZEBO_LIBRARIES})

3.2.3在world中引用

注意这部分代码要插入到sdf模型文件中，joint_two是关节名，要和sdf文件中的一样。

xml 复制代码

    <plugin name="joint_two_control" filename="libjoint_two_control.so">  
	<prismaticJoint>joint_two</prismaticJoint>    
	<P_joint_position_Topic>/joint_two_pos</P_joint_position_Topic>
    </plugin>

最终效果：

二自由度机械臂的gazebo仿真

一、创建ros软件包

二、创建模型文件

1、编写urdf模型文件

2、用rviz查看urdf模型

3、urdf转sdf

三、gazebo仿真

1、编写模型文件

2、编写world文件（导入sdf模型）

2、将world文件导入gazebo（空白世界+world文件）

3、world文件中加入gazebo插件

3.1添加世界插件hello_world

3.1.1编写插件

3.1.2编译插件

3.1.3在world中引用

3.2添加模型插件pos_update

3.2.1编写插件

3.2.2编译插件

3.2.3在world中引用