ROS2入门教程-跨域网络通讯

ROS2入门教程-异地跨域网络通讯

说明:

• 介绍如何异地跨域实现ROS2通讯
• 环境: ubuntu22.04 + humble + n2n (参考)
• 或利用wireguard搭建的基于跨域的内网

跨域的内网搭建步骤:

• 利用n2n的搭建基于跨域的内网,参考教程
• n2n是需要一台主机运行supernode，其他从机运行edge。所有edge通过主机建立交互。
• 假设有ABC三个设备
• 设备A,安装ubuntu下运行supernode的，IP为外网ip，比如：15.4.3.6
• 设备B,安装ubuntu22.04 + ros2的hubmle,运行edge，异地网络，设置局域网内IP为：10.0.0.3
• 设备c,安装ubuntu22.04 + ros2的hubmle,运行edge,本地网络，设置局域网内IP为：10.0.0.4
• 配置成功之后，设备B和设备C就构成一个异地局域网。

设备B,配置中间件步骤:

• 使用cyclonedds中间件
• 增加如下行到~/.bashrc

echo "export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp " >> ~/.bashrc
echo "export CYCLONEDDS_URI=file:///home/ubuntu/cyclonedds.xml " >> ~/.bashrc

• 新增加cyclonedds.xml文件,在用户根目录,假设为/home/ubuntu/
• 文件内容为:

<?xml version="1.0" encoding="UTF-8" ?>
<CycloneDDS xmlns="https://cdds.io/config" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="https://cdds.io/config https://raw.githubusercontent.com/eclipse-cyclonedds/cyclonedds/master/etc/cyclonedds.xsd">
    <Domain Id="any">
        <General>
            <Interfaces>
                <NetworkInterface name="edge0"/>
            </Interfaces>
            <AllowMulticast>default</AllowMulticast>
        </General>
        <Discovery>
            <Peers>
                <Peer address="10.0.0.3"/>
                <Peer address="10.0.0.4"/>
            </Peers>
            <ParticipantIndex>auto</ParticipantIndex>
        </Discovery>
        <Tracing>
            <Verbosity>config</Verbosity>
            <OutputFile>cdds.log.${CYCLONEDDS_PID}</OutputFile>
        </Tracing>
    </Domain>
</CycloneDDS>

设备C,配置中间件步骤:

• 步骤与设备B一样
• 使用cyclonedds中间件
• 增加如下行到~/.bashrc

echo "export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp " >> ~/.bashrc
echo "export CYCLONEDDS_URI=file:///home/ubuntu/cyclonedds.xml " >> ~/.bashrc

• 新增加cyclonedds.xml文件,在用户根目录,假设为/home/ubuntu/
• 文件内容为:

<?xml version="1.0" encoding="UTF-8" ?>
<CycloneDDS xmlns="https://cdds.io/config" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="https://cdds.io/config https://raw.githubusercontent.com/eclipse-cyclonedds/cyclonedds/master/etc/cyclonedds.xsd">
    <Domain Id="any">
        <General>
            <Interfaces>
                <NetworkInterface name="edge0"/>
            </Interfaces>
            <AllowMulticast>default</AllowMulticast>
        </General>
        <Discovery>
            <Peers>
                <Peer address="10.0.0.3"/>
                <Peer address="10.0.0.4"/>
            </Peers>
            <ParticipantIndex>auto</ParticipantIndex>
        </Discovery>
        <Tracing>
            <Verbosity>config</Verbosity>
            <OutputFile>cdds.log.${CYCLONEDDS_PID}</OutputFile>
        </Tracing>
    </Domain>
</CycloneDDS>

测试：

• 在设备B下启动

$ ros2 run demo_nodes_cpp talker
[INFO] [1672128500.852560738] [talker]: Publishing: 'Hello World: 1'
[INFO] [1672128501.852639418] [talker]: Publishing: 'Hello World: 2'
......
[INFO] [1672128502.852623038] [talker]: Publishing: 'Hello World: 3705'
[INFO] [1672128503.852701596] [talker]: Publishing: 'Hello World: 3706'
[INFO] [1672128504.852700431] [talker]: Publishing: 'Hello World: 3707'
[INFO] [1672128505.852761921] [talker]: Publishing: 'Hello World: 3708'
[INFO] [1672128506.852749808] [talker]: Publishing: 'Hello World: 3709'
[INFO] [1672128507.852819464] [talker]: Publishing: 'Hello World: 3710'
[INFO] [1672128508.852827849] [talker]: Publishing: 'Hello World: 3711'
[INFO] [1672128509.852867541] [talker]: Publishing: 'Hello World: 3712'

• 在设备C下输出话题列表

$ ros2 topic list
/chatter
/parameter_events
/rosout

• 在设备C下输出话题内容

$ ros2 topic echo /chatter
data: 'Hello World: 3823'
---
data: 'Hello World: 3824'
---
data: 'Hello World: 3825'
---
data: 'Hello World: 3826'
---

• 正常情况下，能看到话题列表和话题内容