基于 ROS 下使用 Gazebo 机器人

配置机器人模型

xacro 文件
进入到之前创建的 urdf/xacro 下，并创建 mbot_base_gazebo.xacro 文件。
cd ~/catkin_ws/src/mbot_description/urdf/xacro
mkdir gazebo
cd gazebo
sudo gedit mbot_base_gazebo.xacro

粘贴以下代码

<?xml version="1.0"?>
<robot name="mbot" xmlns:xacro="http://www.ros.org/wiki/xacro">

    <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"/>
    <xacro:property name="caster_joint_x" value="0.18"/>


    <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>


    <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>


    <xacro:macro name="wheel" params="prefix reflect">
        <joint name="${prefix}_wheel_joint" type="continuous">
            <origin xyz="0 ${reflect*wheel_joint_y} ${-wheel_joint_z}" rpy="0 0 0"/>
            <parent link="base_link"/>
            <child link="${prefix}_wheel_link"/>
            <axis xyz="0 1 0"/>
        </joint>

        <link name="${prefix}_wheel_link">
            <visual>
                <origin xyz="0 0 0" rpy="${M_PI/2} 0 0" />
                <geometry>
                    <cylinder radius="${wheel_radius}" length = "${wheel_length}"/>
                </geometry>
                <material name="gray" />
            </visual>

            <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>

        <gazebo reference="${prefix}_wheel_link">
            <material>Gazebo/Gray</material>          
        </gazebo>

        <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>
    </xacro:macro>


    <xacro:macro name="caster" params="prefix reflect">
        <joint name="${prefix}_caster_joint" type="continuous">
            <origin xyz="${reflect*caster_joint_x} 0 ${-(base_length/2 + caster_radius)}" rpy="0 0 0"/>
            <parent link="base_link"/>
            <child link="${prefix}_caster_link"/>
            <axis xyz="0 1 0"/>
        </joint>

        <link name="${prefix}_caster_link">
            <visual>
                <origin xyz="0 0 0" rpy="0 0 0"/>
                <geometry>
                    <sphere radius="${caster_radius}" />
                </geometry>
                <material name="black" />
            </visual>

            <collision>