two_bot.launch

<launch>
    <include file="$(find mavros)/launch/apm.launch">
        <arg name="my_ns" value="drone0" /> 
        <arg name="my_url" value="udp://:14550@" />
    </include>

    <include file="$(find mavros)/launch/apm.launch">
        <arg name="my_ns" value="drone1" /> 
        <arg name="my_url" value="udp://:14560@" />
    </include>

    <!--<include file="$(find mavros)/launch/apm.launch">
        <arg name="my_ns" value="drone2" /> 
        <arg name="my_url" value="udp://:14570@" />
    </include>

    <include file="$(find mavros)/launch/apm.launch">
        <arg name="my_ns" value="drone3" /> 
        <arg name="my_url" value="udp://:14570@" />
    </include>

    <include file="$(find mavros)/launch/apm.launch">
        <arg name="my_ns" value="drone4" /> 
        <arg name="my_url" value="udp://:14580@" />
    </include>-->

    <include file="$(find mavros)/launch/apm.launch">
        <arg name="my_ns" value="rover" /> 
        <arg name="my_url" value="udp://:14590@" />
    </include>
</launch>