Add the remaining Inertial Tags for the wheel_link and the caster_wheel_link given the following specifications:

Mass of the wheel_link is 1.0 kg

Mass of the caster_wheel_link is 0.5 kg

The Solution:

Code in the common_properties.xacro file:

The code for the cylinder_inertia:

    <xacro:macro name="cylinder_inertia" params="m h r xyz rpy">
        <inertial>
            <origin xyz="${xyz}" rpy="${rpy}" />
            <mass value="${m}" />
            <inertia ixx="${(m/12) * (h*h + 3*r*r)}" ixy="0" ixz="0"
                     iyy="${(m/12) * (h*h + 3*r*r)}" iyz="0"
                     izz="${0.5*m*r*r}" />
        </inertial>
    </xacro:macro>

The code for the sphere_inertia:

    <xacro:macro name="sphere_inertia" params="m r xyz rpy">
        <inertial>
            <origin xyz="${xyz}" rpy="${rpy}" />
            <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>

Code in the mobile_base.xacro file:

The code for the wheel_link:

    <xacro:macro name="wheel_link" params="prefix">
        <link name="${prefix}_wheel_link">
            <visual>
                <geometry>
                    <cylinder radius="${wheel_radius}" length="${wheel_length}" />
                </geometry>
                <origin xyz="0 0 0" rpy="${pi / 2.0} 0 0" />
                <material name="grey" />
            </visual>
        <xacro:cylinder_inertia m="0.5" h="${wheel_length}" r="${wheel_radius}"
                           xyz="0 0 0" rpy="${pi / 2.0} 0 0" />
        </link>
    </xacro:macro>

The code for the caster_wheel_link:

    <link name="caster_wheel_link">
        <visual>
            <geometry>
                <sphere radius="${wheel_radius / 2.0}" />
            </geometry>
            <origin xyz="0 0 0" rpy="0 0 0" />
            <material name="grey" />
        </visual>
        <xacro:sphere_inertia m="1.0" r="${wheel_radius / 2.0}"
                              xyz="0 0 0" rpy="0 0 0" />
    </link>