The control of four wheel car, mechanical arm and camera in rviz and gazebo
2018年初次接触ROS，做小车路径规划，使用Ubuntu16.04和ROS kinetic
2020年创建此仓库，做机器人爬起行走，使用Ubuntu18.04和ROS melodic
2023年改进此仓库，寻找Robotics实习，使用Ubuntu20.04和ROS noetic
用虚拟机安装Ubuntu
在清华源下载Ubuntu20.04的iso文件
https://blog.csdn.net/weixin_45912291/article/details/108900602
安装虚拟机VMware Workstation 17 Pro
https://blog.csdn.net/weixin_45912291/article/details/108894737
VMware许可证密钥MC60H-DWHD5-H80U9-6V85M-8280D
在虚拟机中安装Ubuntu20.04
https://blog.csdn.net/weixin_45912291/article/details/108901106
全名crescent_velvet
用户名velvet
密码123
虚拟机名称Ubuntu20.04
安装在C盘，硬盘50G，内存8G，处理器2*2
直接安装双系统Ubuntu
使用U盘制作Ubuntu20.04启动盘
进入Ubuntu，更新software，安装code
配置软件源
sudo apt update
cp /etc/apt/sources.list ~/Desktop
sudo gedit /etc/apt/sources.list
将全部内容替换为
# 默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse
# deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-security main restricted universe multiverse
# # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-security main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu/ jammy-security main restricted universe multiverse
# deb-src http://security.ubuntu.com/ubuntu/ jammy-security main restricted universe multiverse
# 预发布软件源，不建议启用
# deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse
# # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse
用sudo权限保存
报错The repository 'http://mirrors.tuna.tsinghua.edu.cn/ros/ubuntu focal Release' is not signed
是因为没有数字签名，无法安全地用清华源更新，所以默认禁用该源
https://blog.csdn.net/Netceor/article/details/118655603
打开网址http://keyserver.ubuntu.com/pks/lookup?op=get&search=0xC1CF6E31E6BADE8868B172B4F42ED6FBAB17C654
将安装证书内容复制保存为ros.asc文件，解决
sudo apt-key add ros.asc
sudo apt update
报错Failed to fetch https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/dists/focal/universe/binary-i386/Packages 404 Not Found [IP: 101.6.15.130 443]
是因为清华源里没有i386，更换华为源，解决
同样是修改/etc/apt/sources.list为
deb https://repo.huaweicloud.com/ubuntu/ focal main restricted
deb https://repo.huaweicloud.com/ubuntu/ focal-updates main restricted
deb https://repo.huaweicloud.com/ubuntu/ focal universe
deb https://repo.huaweicloud.com/ubuntu/ focal-updates universe
deb https://repo.huaweicloud.com/ubuntu/ focal-backports main restricted universe
deb https://repo.huaweicloud.com/ubuntu/ focal-security main restricted
deb https://repo.huaweicloud.com/ubuntu/ focal-security universe
配置公钥
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654
sudo apt-get update
报错keyserver receive failed: Server indicated a failure
不是公钥没有加入Ubuntu服务器，而是VMware还没联网，重启一下就好了
安装ROS
http://wiki.ros.org/cn/Installation/Ubuntu
配置软件源
sudo sh -c '. /etc/lsb-release && echo "deb http://mirrors.tuna.tsinghua.edu.cn/ros/ubuntu/ `lsb_release -cs` main" > /etc/apt/sources.list.d/ros-latest.list'
注意，系统软件源用了华为源，而ros软件源这里用了清华源，懒得改
sudo apt update
sudo apt install ros-noetic-desktop-full
apt search ros-noetic
echo "source /opt/ros/noetic/setup.bash" >> ~/.bashrc
source ~/.bashrc
安装构建依赖
sudo apt install python3-rosdep python3-rosinstall python3-rosinstall-generator python3-wstool build-essential
sudo rosdep init
rosdep update
报错The read operation timed out
是因为raw.githubusercontent.com被墙了
改用国内的rosdepc，解决
sudo apt install python3-pip
sudo pip install rosdepc
sudo rosdepc init
rosdep update
测试ROS是否安装成功
开启第一个终端，初始化ROS环境
roscore
开启第二个终端，启动图形化界面
rosrun turtlesim turtlesim_node
开启第三个终端，查看节点通信
rosrun rqt_graph rqt_graph
开启第四个终端，启动运动控制
rosrun turtlesim turtle_teleop_key
成功实现键盘控制小乌龟运动
报错Command 'roscore' not found
报错package 'turtlesim' not found
报错package 'rqt_graph' not found
是依赖项没安装，解决
sudo apt install ros-noetic-roslaunch
sudo apt install ros-noetic-ros-tutorials
sudo apt install ros-noetic-rqt-graph
报错Done checking log file disk usage. Usage is <1GB
是因为roslaunch安装错版本了
不应该sudo apt install python3-roslaunch，但也卸不掉，直接安装noetic版本，解决
sudo apt install ros-noetic-roslaunch
报错Command 'rosrun' not found
是依赖项没安装
不能按照提示安装sudo apt install rosbash，应该安装noetic版本，解决
sudo apt install ros-noetic-rosbash
配置Git密钥
git --version
git config --global user.name "velvet"
git config --global user.email "[email protected]"
git config --global --list
ssh-keygen -t rsa -C "[email protected]"
cat ~/.ssh/id_rsa.pub
复制到GitHub的SSH keys中，命名为ruby_1801newPC_ubuntu
插入U盘，在VMware的菜单栏，选择虚拟机，选择可移动设备，选择小米U盘，选择连接虚拟机断开主机
U盘无法读取，因为虚拟机设置中只支持USB2.0
挂起状态无法编辑虚拟机设置，需要关机才行。在绿色三角形开启图标下，有关机选项，选择关机，放弃挂起状态，编辑虚拟机设置，修改USB兼容性为3.1，显示所有USB输入设备
虚拟机开机，在VMware的菜单栏，选择虚拟机，选择可移动设备，选择小米U盘，选择连接虚拟机断开主机，成功连接
安装Ubuntu20.04，ros-noetic，gazebo，下载本仓库放入catkin_ws/src
mkdir ~/catkin_ws
mkdir ~/catkin_ws/src
cd ~/catkin_ws/src
git clone [email protected]:CrescentVelvet/dancer_car.git
cd ..
catkin_make
source devel/setup.bash
报错The specified source space "/home/velvet/catkin_ws/src/src" does not exist
是误入src文件夹了，cd ..，解决
报错Could not find a package configuration file provided by "controller_manager"
报错Could not find a package configuration file provided by "effort_controllers"
报错Could not find a package configuration file provided by "gazebo"
报错Could not find a package configuration file provided by "gazebo_plugins"
报错Could not find a package configuration file provided by "gazebo_ros"
报错Could not find a package configuration file provided by "gazebo_ros_control"
报错Could not find a package configuration file provided by "joint_state_controller"
报错Could not find a package configuration file provided by "robot_state_publisher"
报错Could not find a package configuration file provided by "joint_state_publisher"
报错Could not find a package configuration file provided by "joint_state_publisher_gui"
报错Could not find a package configuration file provided by "rqt_gui"
报错Could not find a package configuration file provided by "rviz"
报错Could not find a package configuration file provided by "xacro"
报错Could not find a package configuration file provided by "pr2_controller_manager"
报错Could not find a package configuration file provided by "fake_localization"
报错Could not find a package configuration file provided by "teleop_twist_keyboard"
是各种依赖项没安装，解决
sudo apt install ros-noetic-controller-manager
sudo apt install ros-noetic-effort-controllers
sudo apt install gazebo11
sudo apt install libgazebo11-dev
sudo apt install ros-noetic-gazebo-ros-pkgs
sudo apt install ros-noetic-gazebo-ros-control
sudo apt install ros-noetic-joint-state-controller
sudo apt install ros-noetic-robot-state-publisher
sudo apt install ros-noetic-joint-state-publisher
sudo apt install ros-noetic-joint-state-publisher-gui
sudo apt install ros-noetic-rviz
sudo apt install ros-noetic-xacro
sudo apt install ros-noetic-pr2-controller-manager
sudo apt install ros-noetic-fake-localization
sudo apt install ros-noetic-teleop-twist-keyboard
rosstack profile
rospack profile
rospack list
安装后依然报错找不到gazebo
估计是创建包时写的gazebo写错了，把~/catkin_ws/src/CMakeLists.txt，以及car_control，car_keyboard，car_model文件夹的CMakeLists.txt中find_package的gazebo删掉，解决
报错RLException: [display.launch] is neither a launch file in package [car_model] nor is [car_model] a launch file name
是因为忘记刷新了，source devel/setup.bash，解决
查看模型
cd ~/catkin_ws
roslaunch car_model display.launch
将Global Options的Fixed Frame选取为world_link
在左下角Add添加部件RobotModel和Camera
在冒出来的gui小窗口上控制关节转动
效果如图
找不到gui小窗口，先安装依赖包sudo apt install ros-noetic-joint-state-publisher-gui
将~/catkin_ws/src/dancer_car/car_model/launch/display.launch中的
<arg name="gui" default="False" />
<node name="joint_state_publisher"
pkg="joint_state_publisher"
type="joint_state_publisher" />
修改为
<arg name="gui" default="True" />
<node name="joint_state_publisher_gui"
pkg="joint_state_publisher_gui"
type="joint_state_publisher_gui" />
警告'state_publisher' executable is deprecated
将~/catkin_ws/src/dancer_car/car_model/launch/display.launch中的
<node name="state_publisher"
pkg="state_publisher"
type="state_publisher" />
修改为
<node name="robot_state_publisher"
pkg="robot_state_publisher"
type="robot_state_publisher" />
警告'use_gui' parameter was specified
没啥用，忽略
加载场景地图
sudo scp -r ~/catkin_ws/src/dancer_car/car_model/worlds/car_world02.jpg /usr/share/gazebo-11/media/materials/textures/car_world.jpg
sudo scp -r ~/catkin_ws/src/dancer_car/car_model/worlds/gazebo.material /usr/share/gazebo-11/media/materials/scripts/gazebo.material
键盘控制小车
cd ~/catkin_ws
roslaunch car_model gazebo.launch
效果如图
控制前进后退与转弯
|---|---|---|-------------|
| u | i | o | 左右方向前进 |
| j | k | l | 原地转与停止 |
| m | < | > | 左右方向后退 |
|---|---|---|-------------|
控制加速减速与角度
|---|---|----------------|
| q | a | 线速度加减速10% |
| w | s | 角速度加减速10% |
|---|---|----------------|
控制三根杆子运动
|---|---|-----------|
| r | t | 杆子一转动 |
| f | g | 杆子二摆动 |
| v | b | 杆子三转动 |
|---|---|-----------|
报错找不到gazebo/spawn_model
将~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中的
<!-- car model -->
<node name="spawn_model"
pkg="gazebo"
修改为
<!-- car model -->
<node name="spawn_model"
pkg="gazebo_ros"
报错找不到gazebo_world
将~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中的
<include file="$(find gazebo_world)/launch/empty_world.launch">
修改为
<include file="$(find gazebo_ros)/launch/empty_world.launch">
运行gazebo时黑屏
是进程没结束，以后要先关闭gazebo页面再Ctrl+C结束终端
killall gzserver
报错找不到robot_description
使用urdf文件时，在~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中添加
<param name="robot_description" textfile="$(find car_model)/robots/car_model.URDF"/>
使用xacro文件时，在~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中添加
<param name="robot_description" command="$(find xacro)/xacro --inorder '$(find car_model)/robots/car_model.xacro'" />
警告KDL does not support a root link with an inertia
给root link添加一个不具有inertia的parent
警告Deprecated syntax
将~/catkin_ws/src/dancer_car/car_model/robots/car_model.xacro中的
<transmission name="tran_column_link1">
<type>transmission_interface/SimpleTransmission</type>
<joint name="joint_column_link1">
<hardwareInterface>EffortJointInterface</hardwareInterface>
修改为
<transmission name="tran_column_link1">
<type>transmission_interface/SimpleTransmission</type>
<joint name="joint_column_link1">
<hardwareInterface>hardware_interface/EffortJointInterface</hardwareInterface>
报错new node registered with same name
是节点名称冲突，直接删掉~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中的
<include file="$(find pr2_controller_manager)/controller_manager.launch" />
报错Error in REST request，警告找不到api.ignitionfuel.org
将home/.ignition/fuel/config.yaml中的URL行的api.ignitionfuel.org修改为api.ignitionrobotics.org
小车各个零部件固定在原点一动不动，或者小车狂舞乱飞无法无天 是因为质量、摩擦力设置过小，PID参数设置有误，在~/catkin_ws/src/dancer_car/car_model/config/car_control.yaml中修改
报错cmd /opt/ros/melodic/lib/gazebo_ros/spawn_model 将~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中$(find car_model)/robots/car_model.URDF-urdf -model car_model"的urdf中间加个空格
control启动（控制吊杆运动）（无用）
roslaunch car_control robot_control.launch
手动输入指令（无用）
rostopic pub -1 /car_model/joint_column_link1_controller/command std_msgs/Float64 "data: 1.5"
rostopic pub -1 /car_model/joint_column_link2_controller/command std_msgs/Float64 "data: 1.5"
rostopic pub -1 /car_model/joint_column_link3_controller/command std_msgs/Float64 "data: 1.5"
输入指令为转动关节角度的弧度值[-PI,PI]
使用rqt发布指令（无用）
rosrun rqt_gui rqt_gui
在Topics中选择Message Publisher，
添加/car_model/joint_column_link1_controller/command
设置frequency为100Hz，设置data为sin(i/100)
添加/car_model/joint_column_link2_controller/command
设置frequency为100Hz，设置data为sin(i/100)*3
添加/car_model/joint_column_link3_controller/command
设置frequency为100Hz，设置data为sin(i/50)
在前面的框中打钩，控制杆子转动
报错RLException: roslaunch file contains multiple nodes named [/robot_state_publisher]
报错[ERROR] [1681570294.287918622, 0.644000000]: A controller named 'joint_state_controller' was already loaded inside the controller manager 是因为gazebo.launch启动了robot_control.launch，两个文件的控制器重名了，不需要启动robot_control.launch， 直接删掉~/catkin_ws/src/dancer_car/car_model/launch/gazebo.launch中的
<include file="$(find car_control)/launch/robot_control.launch" />
在空白gazebo中添加模型
roslaunch gazebo_ros empty_world.launch
添加urdf模型文件
rosrun gazebo_ros spawn_model -file $(find car_model)/robots/car_model.URDF -urdf -z 1 -model car_model.URDF
添加xacro模型文件
rosrun gazebo_ros spawn_model -file $(find car_model)/robots/car_model.xacro -xacro -z 1 -model car_model.xacro
插件安装
github上有sw2urdfSetup插件，可以将SolidWorks模型转换成urdf文件，但是原作者删除了exe版本，需要自己编译，或者可以在CSDN上下载exe版本
导出教程：https://zhuanlan.zhihu.com/p/114300275
安装在SolidWorks的安装文件夹内即可
转轴配置
对于装配体，选择file导出到urdf，在PropertyManager建立link和子link，选择对应的零部件
在FeatureManager，选择Insert ReferenceGeometry，选择Axis轴，圆柱体中心线，重命名
坐标系建立
在FeatureManager，选择Insert ReferenceGeometry，选择Point点，圆形中点
与转轴一起选中，插入Coordinate System，点击x轴前面的箭头调整方向，重命名
在Preview and Export里把每个link对应的转轴与坐标系选择好，输出为文件夹
安装urdf各种辅助功能插件
sudo apt install liburdfdom-tools
检查urdf有无语法错误
cd ~/catkin_ws/src/dancer_car/car_model/robots
check_urdf car_model.urdf
得到结果
robot name is: car_model
---------- Successfully Parsed XML ---------------
root Link: world_link has 1 child(ren)
child(1): car_body
child(1): column_link1
child(1): column_link2
child(1): column_link3
child(1): camera_link
child(2): left_back_wheel
child(3): left_front_wheel
child(4): right_back_wheel
child(5): right_front_wheel
生成pdf图片文件展示urdf里的父子关系
cd ~/catkin_ws/src/dancer_car/car_model/robots
urdf_to_graphiz car_model.urdf
结果如图
urdf转换为sdf文件
cd ~/catkin_ws/src/dancer_car/car_model/robots
gz sdf -p car_model.urdf
xacro转换为urdf文件
cd ~/catkin_ws/src/dancer_car/car_model/robots
rosrun xacro xacro car_model.xacro > car_model.urdf
报错[rosrun] Couldn't find executable named xacro.py below /opt/ros/noetic/share/xacro
是因为xacro.py已被舍弃，改为xacro无后缀，即可
直接手写创建urdf模型文件
第一步，写link部件，计算collision碰撞，visual可视化，inertial转动惯量
<link name="car_body">
<collision>
<origin
xyz="0 0 ${car_c/2}"
rpy="0 0 0" />
<geometry>
<box size="${car_a} ${car_b} ${car_c}" />
</geometry>
</collision>
<visual>
<origin
xyz="0 0 ${car_c/2}"
rpy="0 0 0" />
<geometry>
<box size="${car_a} ${car_b} ${car_c}" />
</geometry>
<material name="blue">
<color rgba="0 0.5 0.8 1"/>
</material>
</visual>
<inertial>
<origin
xyz="0 0 ${car_c/2}"
rpy="0 0 0" />
<mass value="${car_mass}" />
<inertia
ixx="${car_mass / 12.0 * (car_b*car_b + car_c*car_c)}"
ixy="0.0"
ixz="0.0"
iyy="${car_mass / 12.0 * (car_a*car_a + car_c*car_c)}"
iyz="0.0"
izz="${car_mass / 12.0 * (car_a*car_a + car_b*car_b)}" />
</inertial>
</link>
第二步，写joint关节，用fixed固定和continuous活动来连接两个link，设置力矩和摩擦力
<joint name="joint_column_link1" type="continuous">
<axis xyz="0 0 1" rpy="0 0 0" />
<parent link="car_body" />
<child link="column_link1" />
<origin xyz="${car_a/2-column_width} 0 ${car_c}" />
<limit effort="100" velocity="100" />
<joint_properties damping="0" friction="0" />
</joint>
第三步，创建小车机械臂模型功能包car_model
cd ~/catkin_ws/src/dancer_car
catkin_create_pkg car_model joint_state_publisher robot_state_publisher rviz gazebo_plugins gazebo_ros gazebo_ros_control xacro car_control
第四步，把car_model.urdf文件放入~/catkin_ws/src/dancer_car/car_model/robots文件夹中
把display.launch和gazebo.launch文件都放入~/catkin_ws/src/dancer_car/car_model/launch文件夹中
urdf转换为xacro文件
第一步，在urdf文件开头添加
<robot name="car_model" xmlns:xacro="http://www.ros.org/wiki/xacro">
第二步，添加一个虚拟的世界坐标，用joint关节将小车和世界坐标连在一起
<link name="world_link">
</link>
<joint name="joint_world" type="fixed">
<parent link="world_link" />
<child link="car_body" />
</joint>
第三步，为每一个joint关节添加transmission驱动标签，使得关节能够被驱动控制
注意，这里的hardware_interface/PositionJointInterface是关节位置控制，直接控制关节运动的位置
而hardwareInterface/EffortJointInterface是关节力矩控制，如果inertial中的inertia转动惯量矩阵设置不对，机械臂就抬不起来
<transmission name="tran_column_link1">
<!-- 指定传动类型 -->
<type>transmission_interface/SimpleTransmission</type>
<!-- 传动系统所连接的关节 -->
<joint name="joint_column_link1">
<!-- 指定硬件接口，注意，当在Gazebo中加载此传动系统是，值应为EffortJointInterface -->
<!-- 而在RobotHW中加载此传动系统时，值应为hardware_interface/EffortJointInterface -->
<!-- 另外，位置控制是JointPositionController，力矩控制是EffortJointInterface -->
<hardwareInterface>hardware_interface/EffortJointInterface</hardwareInterface>
</joint>
<actuator name="motor_column_link1">
<!-- 可选，指定硬件接口 -->
<hardwareInterface>hardware_interface/EffortJointInterface</hardwareInterface>
<!-- 可选，指定关节制动器之间机械减速比，并非所有传动系统都需要此标签 -->
<mechanicalReduction>1</mechanicalReduction>
<motorTorqueConstant>1</motorTorqueConstant>
</actuator>
</transmission>
第四步，添加gazebo plugin插件
将ROS和gazebo仿真环境连接起来
<gazebo>
<plugin name="gazebo_ros_control"
filename="libgazebo_ros_control.so">
<robotNamespace>/car_model</robotNamespace>
<robotSimType>gazebo_ros_control/DefaultRobotHWSim</robotSimType>
</plugin>
</gazebo>
第五步，添加gazebo reference插件
为gazebo中的小车机械臂设置颜色与摩擦力
之前link中设置的颜色只能在rviz中显示，不能在gazebo中显示
<gazebo reference="column_link1">
<mu1>0.2</mu1>
<mu2>0.2</mu2>
<material>Gazebo/Green</material>
</gazebo>
第六步，修改display.launch文件中的读取模式
<param name="robot_description"
command="$(find xacro)/xacro --inorder '$(find car_model)/robots/car_model.xacro'" />
第七步，修改gazebo.launch文件中的读取模式
<param name="robot_description"
command="$(find xacro)/xacro --inorder '$(find car_model)/robots/car_model.xacro'" />
第八步，在~/catkin_ws/src/dancer_car/car_model/config文件夹下创建car_control.yaml参数文件，写入关节控制器的PID参数
注意，如果第三步transmission中用了关节位置控制，这里要用position_controllers/JointPositionController
如果transmission中用了关节力矩控制，这里要用effort_controllers/JointPositionController
joint_state_controller:
type: joint_state_controller/JointStateController
publish_rate: 50
joint_column_link1_controller:
type: effort_controllers/JointPositionController
joint: joint_column_link1
pid: {p: 10.0, i: 0.01, d: 0}
第九步，在gazebo.launch文件中添加一行
加载car_model里的car_control.yaml参数文件，而不是car_control里的robot_control.yaml
注意，不需要car_control控制功能包，xacro模型文件和yaml参数文件全都放进car_model模型功能包中即可
<rosparam file="$(find car_model)/config/car_control.yaml" command="load"/>
第十步，在gazebo.launch文件中添加机械臂关节控制
<node name="joint_controller_spawner"
pkg="controller_manager"
type="spawner"
respawn="false"
output="screen"
ns="/car_model"
args="joint_state_controller
joint_column_link1_controller
joint_column_link2_controller
joint_column_link3_controller"/>
第十一步，在gazebo.launch文件中添加小车速度控制
<node name="control_vel"
pkg="car_keyboard"
type="car_keyboard.py"
output="screen" />
总结一下，无需car_control，用car_model里的yaml文件来控制机械臂运动，用car_keyboard里的py文件来控制小车运动
urdf
link: collision, visual, inertial
joint: axis, parent, child, origin, effort, friction
xacro
world_link, fixed joint
transmission: PositionJointInterface, EffortJointInterface
gazebo_ros_control
gazebo reference: mu1, mu2, material
yaml
joint_column_link1_controller: position_controllers, effort_controllers
launch
node: joint_controller_spawner, control_vel
catkin_create_pkg car_model joint_state_publisher robot_state_publisher rviz gazebo_plugins gazebo_ros gazebo_ros_control xacro car_control
编写xacro文件和launch文件，link与joint，以及collision、visual、inertial
catkin_create_pkg car_control controller_manager joint_state_controller robot_state_publisher rqt_gui effort_controllers rviz gazebo_ros gazebo_plugins gazebo_ros_control xacro
编写yaml文件和launch文件，gazebo reference、transmission、gazebo plugin
运行rviz或gazebo时，开启ROS QT可视化工具显示节点node状态关系图
rosrun rqt_graph rqt_graph
rostopic pub -1 /car_model/joint_column_link1_controller/command std_msgs/Float64 "data: 1.5"
全部节点如图
当前节点如图
列出所有node订阅和发布topic的信息
查看node在指定topic上发布的数据及类型
rostopic list -v
rostopic echo <topic>
rostopic type <topic>
查看node输出信息
rosrun rqt_console rqt_console
sin(i/rate*speed)*diff + offset
rate是频率，speed是速度系数，diff是上下界之差，offset是上界减去diff