clover/clover_description/urdf/leds/led_strip.xacro

<?xml version="1.0" encoding="UTF-8"?>
<robot name="led_strip" xmlns:xacro="http://ros.org/wiki/xacro">

    <!-- LED strip macro
        Parameters:
          name: Name of the LED strip
          parent: Name of the parent link (likely to be base_link)
          radius: Radius of the strip
          bulb_radius: Radius (for spheres)/side (for boxes) of the LED
          led_count: Number of LEDs in a strip
          use_plugin: Attach the controller plugin to LEDs
    -->
    <xacro:macro name="led_strip" params="name parent radius:=0.08 bulb_radius:=0.005 led_count:=58 shift:=0 use_plugin:=false x:=0 y:=0 z:=0 roll:=0 pitch:=0 yaw:=0">
        <joint name="${name}_joint" type="fixed">
            <origin xyz="${x} ${y} ${z}"
                    rpy="${roll} ${pitch} ${yaw}"/>
            <parent link="${parent}"/>
            <child link="${name}_link"/>
        </joint>

        <link name="${name}_link">
            <inertial>
                <origin xyz="0 0 0"/>
                <mass value="0.0001"/>
                <inertia ixx="0.001" ixy="0.0" ixz="0.0" iyy="0.001" iyz="0.0" izz="0.001"/>
            </inertial>

            <xacro:macro name="loop_links" params="link_i links_total">
                <visual>
                    <origin xyz="${radius*cos(2 * pi * link_i / links_total)} ${radius*sin(2 * pi * link_i / links_total)} 0"
                            rpy="0 0 ${2 * pi * link_i / links_total}"/>
                    <geometry>
                        <box size="${bulb_radius} ${bulb_radius} ${bulb_radius}"/>
                    </geometry>
                </visual>
                <xacro:unless value="${link_i + 1 == links_total}">
                    <xacro:loop_links link_i="${link_i + 1}" links_total="${links_total}"/>
                </xacro:unless>
            </xacro:macro>
            <xacro:loop_links link_i="0" links_total="${led_count}"/>
        </link>

        <xacro:if value="${use_plugin}">
        <gazebo reference="${name}_link">
            <visual>
                <plugin name="${name}_controller" filename="libsim_leds.so">
                    <robotNamespace></robotNamespace>
                    <ledCount>${led_count}</ledCount>
                </plugin>
                <cast_shadows>false</cast_shadows>
                <material>
                    <ambient>0 0 0 1</ambient>
                    <diffuse>0 0 0 1</diffuse>
                    <specular>0 0 0 1</specular>
                    <emissive>0 0 0 1</emissive>
                </material>
            </visual>
        </gazebo>
        </xacro:if>
        <gazebo reference="${name}_joint">
            <disableFixedJointLumping>true</disableFixedJointLumping>
            <preserveFixedJoint>true</preserveFixedJoint>
        </gazebo>
        <!-- <gazebo>
            <static>true</static>
        </gazebo> -->
        <gazebo>
            <plugin name="${name}_ros_controller" filename="libsim_leds_controller.so">
                <robotNamespace></robotNamespace>
                <ledCount>${led_count}</ledCount>
            </plugin>
        </gazebo>
    </xacro:macro>

</robot>