gazebo模块化建模+控制器+传感器
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2022-06-23 20:58:16
使用xacro模块化建模定义常量:
使用xacro模块化建模
定义常量:
<xacro:property name="M_PI" value="3.1415926"/>
<xacro:property name="base_mass" value="20" />
<xacro:property name="base_radius" value="0.20"/>
<xacro:property name="base_length" value="0.16"/>
<xacro:property name="wheel_mass" value="2" />
<xacro:property name="wheel_radius" value="0.06"/>
<xacro:property name="wheel_length" value="0.025"/>
<xacro:property name="wheel_joint_y" value="0.19"/>
<xacro:property name="wheel_joint_z" value="0.05"/>
<xacro:property name="caster_mass" value="0.5" />
<xacro:property name="caster_radius" value="0.015"/> <!-- wheel_radius - ( base_length/2 - wheel_joint_z) -->
<xacro:property name="caster_joint_x" value="0.18"/>
定义颜色:
<!-- Defining the colors used in this robot -->
<material name="yellow">
<color rgba="1 0.4 0 1"/>
</material>
<material name="black">
<color rgba="0 0 0 0.95"/>
</material>
<material name="gray">
<color rgba="0.75 0.75 0.75 1"/>
</material>
宏定义:
<xacro:macro name="sphere_inertial_matrix" params="m r">
<!-- Macro for robot wheel -->
<xacro:macro name="wheel" params="prefix1 prefix2 reflect1 reflect2">
<joint name="${prefix1}_${prefix2}_wheel_joint" type="continuous">
<axis xyz="0 0 1"/>
<origin xyz="${reflect1} ${reflect2} -0.05" rpy="0 1.57075 0"/>
<parent link="base_link"/>
<child link="${prefix1}_${prefix2}_wheel_link"/>
</joint>
<link name="${prefix1}_${prefix2}_wheel_link">
<visual>
<geometry>
<cylinder radius="${wheel_radius}" length = "${wheel_length}"/>
</geometry>
<material name="gray" />
</visual>
<collision>
<geometry>
<cylinder radius="${wheel_radius}" length = "${wheel_length}"/>
</geometry>
</collision>
<cylinder_inertial_matrix m="${wheel_mass}" r="${wheel_radius}" h="${wheel_length}" />
</link>
<gazebo reference="${prefix1}_${prefix2}_wheel_link">
<material>Gazebo/Gray</material>
</gazebo>
<!-- Macro for inertia matrix -->
<xacro:macro name="sphere_inertial_matrix" params="m r">
<inertial>
<mass value="${m}" />
<inertia ixx="${2*m*r*r/5}" ixy="0" ixz="0"
iyy="${2*m*r*r/5}" iyz="0"
izz="${2*m*r*r/5}" />
</inertial>
</xacro:macro>
<xacro:macro name="cylinder_inertial_matrix" params="m r h">
<inertial>
<mass value="${m}" />
<inertia ixx="${m*(3*r*r+h*h)/12}" ixy = "0" ixz = "0"
iyy="${m*(3*r*r+h*h)/12}" iyz = "0"
izz="${m*r*r/2}" />
</inertial>
</xacro:macro>
宏调用
<cylinder_inertial_matrix m="${wheel_mass}" r="${wheel_radius}" h="${wheel_length}" />
<wheel prefix1="front" prefix2="left" reflect1="-0.15" reflect2="0.15"/>
<wheel prefix1="front" prefix2="right" reflect1="0.15" reflect2="0.15"/>
<wheel prefix1="back" prefix2="left" reflect1="-0.15" reflect2="-0.15"/>
<wheel prefix1="back" prefix2="right" reflect1="0.15" reflect2="-0.15"/>
文件包含
调用其他已定义好的模型, 可以实现模块化建模
<xacro:include filename="$(find mbot_description)/urdf/mbot_base_gazebo.xacro" />
优化物理模型
为了实现物理仿真，需要对模型添加惯性参数和碰撞属性
<collision>
<origin xyz="0 0 0" rpy="${M_PI/2} 0 0" />
<geometry>
<cylinder radius="${wheel_radius}" length = "${wheel_length}"/>
</geometry>
</collision>
<cylinder_inertial_matrix m="${wheel_mass}" r="${wheel_radius}" h="${wheel_length}" />
</link>
碰撞属性一般是指其碰撞的面积，为了便于计算，可以将其简化为规则形状
为link添加gazebo标签
gazebo中标签无颜色，需在此设置
<gazebo reference="base_link">
<material>Gazebo/Blue</material>
</gazebo>
为jiont添加传动装置 （相当于电机）
<transmission name="${prefix}_wheel_joint_trans">
<type>transmission_interface/SimpleTransmission</type>
<joint name="${prefix}_wheel_joint" >
<hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
</joint>
<actuator name="${prefix}_wheel_joint_motor">
<hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
<mechanicalReduction>1</mechanicalReduction>
</actuator>
</transmission>
添加gazebo控制器插件
<!-- Drive controller -->
<gazebo>
<plugin name="skid_steer_drive_controller" filename="libgazebo_ros_skid_steer_drive.so">
<updateRate>100.0</updateRate>
<robotNamespace>/</robotNamespace>
<leftFrontJoint>front_left_wheel_joint</leftFrontJoint>
<rightFrontJoint>front_right_wheel_joint</rightFrontJoint>
<leftRearJoint>back_left_wheel_joint</leftRearJoint>
<rightRearJoint>back_right_wheel_joint</rightRearJoint>
<wheelSeparation>4</wheelSeparation>
<wheelDiameter>0.1</wheelDiameter>
<robotBaseFrame>base_link</robotBaseFrame>
<torque>1</torque>
<topicName>cmd_vel</topicName>
<broadcastTF>0</broadcastTF>
</plugin>
</gazebo>
具体参数设置: http://gazebosim.org/tutorials?tut=ros_gzplugins#DifferentialDrive
也可以采用Ackermann转向驱动。
添加传感器仿真
可以使用gazebo的传感器模型，然后在主模型文件中添加该模型到base_link上
其他模型详见:Plugins available in gazebo_plugins
http://gazebosim.org/tutorials?tut=ros_gzplugins#OpenniKinect
<?xml version="1.0"?>
<robot name="my_car" xmlns:xacro="http://www.ros.org/wiki/xacro">
<xacro:include filename="$(find my_car)/urdf/my_car_base.xacro" />
<xacro:include filename="$(find my_car)/urdf/sensors/kinect_gazebo.xacro" />
<xacro:include filename="$(find my_car)/urdf/sensors/camera_gazebo.xacro" />
<xacro:property name="kinect_offset_x" value="0" />
<xacro:property name="kinect_offset_y" value="0.2" />
<xacro:property name="kinect_offset_z" value="0.11" />
<!-- kinect -->
<joint name="kinect_joint" type="fixed">
<origin xyz="${kinect_offset_x} ${kinect_offset_y} ${kinect_offset_z}" rpy="0 0 1.57" />
<parent link="base_link"/>
<child link="kinect_link"/>
</joint>
<!-- Camera -->
<xacro:kinect_camera prefix="kinect"/>
<xacro:property name="camera_offset_x" value="0.17" />
<xacro:property name="camera_offset_y" value="0" />
<xacro:property name="camera_offset_z" value="0.10" />
<joint name="camera_joint" type="fixed">
<origin xyz="${camera_offset_x} ${camera_offset_y} ${camera_offset_z}" rpy="0 0 0" />
<parent link="base_link"/>
<child link="camera_link"/>
</joint>
<xacro:usb_camera prefix="camera"/>
<my_car_base/>
</robot>
启动文件
<launch>
<!-- 设置launch文件的参数 -->
<arg name="world_name" value="$(find my_car)/worlds/playground.world"/>
<arg name="paused" default="false"/>
<arg name="use_sim_time" default="true"/>
<arg name="gui" default="true"/>
<arg name="headless" default="false"/>
<arg name="debug" default="false"/>
<!-- 运行gazebo仿真环境 -->
<include file="$(find gazebo_ros)/launch/empty_world.launch">
<arg name="world_name" value="$(arg world_name)" />
<arg name="debug" value="$(arg debug)" />
<arg name="gui" value="$(arg gui)" />
<arg name="paused" value="$(arg paused)"/>
<arg name="use_sim_time" value="$(arg use_sim_time)"/>
<arg name="headless" value="$(arg headless)"/>
</include>
<!-- 加载机器人模型描述参数 -->
<param name="robot_description" command="$(find xacro)/xacro --inorder '$(find my_car)/urdf/my_car_base_with_rgbd.xacro'" />
<!-- run node joint-state-pub，publish joint_state -->
<node name="joint_state_publisher_gui" pkg = "joint_state_publisher_gui" type = "joint_state_publisher_gui" />
<!--run node robot_state_publisher, publish tf-->
<node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher" output="screen" >
<param name="publish_frequency" type="double" value="50.0" />
</node>
<!-- 在gazebo中加载机器人模型-->
<node name="urdf_spawner" pkg="gazebo_ros" type="spawn_model" respawn="false" output="screen"
args="-urdf -model my_car -param robot_description"/>
<!--run rviz-->
<node name="rviz" pkg = "rviz" type = "rviz" args = "-d $(find my_car)/config/my_car_with_rgbd.rviz" />
</launch>
其他可以不用修改，下次直接使用
本文地址：https://blog.csdn.net/unspoken0714/article/details/108583708