ROS2入门教程-使用ROS1bridge记录和回放topic数据

说明：

• 介绍如何使用ROS1bridge记录和回放topic数据

步骤：

• 运行 ROS 1 roscore

# Shell A:
. /opt/ros/kinetic/setup.bash
# Or, on OSX, something like:
# . ~/ros_catkin_ws/install_isolated/setup.bash
roscore

• 运行ROS 1 <=> ROS 2 dynamic_bridge

# Shell B:
. /opt/ros/kinetic/setup.bash
# Or, on OSX, something like:
# . ~/ros_catkin_ws/install_isolated/setup.bash
. /opt/ros/ardent/setup.bash
# Or, if building ROS 2 from source:
# . <workspace-with-bridge>/install/setup.bash
export ROS_MASTER_URI=http://localhost:11311
ros2 run ros1_bridge dynamic_bridge --bridge-all-topics

• 启动 ROS 2 程序来模拟我们的乌龟式机器人，将cam2image使用该-b选项运行程序

# Shell C:
. /opt/ros/ardent/setup.bash
# Or, if building ROS 2 from source:
# . <workspace-with-bridge>/install/setup.bash
ros2 run image_tools cam2image -- -b

• 运行一个简单的 Python 脚本来模拟来自 Kobuki 基础的odom和imu_data主题

#!/usr/bin/env python3

import sys
import time

import rclpy

from nav_msgs.msg import Odometry
from sensor_msgs.msg import Imu

def main():
    rclpy.init(args=sys.argv)

    node = rclpy.create_node('emulate_kobuki_node')

    imu_publisher = node.create_publisher(Imu, 'imu_data')
    odom_publisher = node.create_publisher(Odometry, 'odom')

    imu_msg = Imu()
    odom_msg = Odometry()
    counter = 0
    while True:
        counter += 1
        now = time.time()
        if (counter % 50) == 0:
            odom_msg.header.stamp.sec = int(now)
            odom_msg.header.stamp.nanosec = int(now * 1e9) % 1000000000
            odom_publisher.publish(odom_msg)
        if (counter % 100) == 0:
            imu_msg.header.stamp.sec = int(now)
            imu_msg.header.stamp.nanosec = int(now * 1e9) % 1000000000
            imu_publisher.publish(imu_msg)
            counter = 0
        time.sleep(0.001)


if __name__ == '__main__':
    sys.exit(main())

• 在新的 ROS 2 shell 中运行此 python 脚本

# Shell D:
. /opt/ros/ardent/setup.bash
# Or, if building ROS 2 from source:
# . <workspace-with-bridge>/install/setup.bash
python3 emulate_kobuki_node.py

• 在新的 ROS 1 shell 中查看可用主题

# Shell E:
. /opt/ros/kinetic/setup.bash
# Or, on OSX, something like:
# . ~/ros_catkin_ws/install_isolated/setup.bash
rostopic list

• 结果如下：

% rostopic list
/image
/imu_data
/odom
/rosout
/rosout_agg

• 在同一个 shell 中记录这些数据

# Shell E:
rosbag record /image /imu_data /odom

• 几秒钟后，您可以Ctrl-c执行rosbag命令并查看文件有多大，结果如下：

% ls -lh
total 0
-rw-rw-r-- 1 william william  12M Feb 23 16:59 2017-02-23-16-59-47.bag

• 使用 rosbag 和 ROS 1 Bridge 回放主题数据

• 在一个新的 shell 中启动roscore

# Shell P:
. /opt/ros/kinetic/setup.bash
# Or, on OSX, something like:
# . ~/ros_catkin_ws/install_isolated/setup.bash
roscore

• 在另一个shell中运行dynamic_bridge

# Shell Q:
. /opt/ros/kinetic/setup.bash
# Or, on OSX, something like:
# . ~/ros_catkin_ws/install_isolated/setup.bash
. /opt/ros/ardent/setup.bash
# Or, if building ROS 2 from source:
# . <workspace-with-bridge>/install/setup.bash
export ROS_MASTER_URI=http://localhost:11311
ros2 run ros1_bridge dynamic_bridge --bridge-all-topics

• 在另一个新 shell 中播放包数据

# Shell R:
. /opt/ros/kinetic/setup.bash
# Or, on OSX, something like:
# . ~/ros_catkin_ws/install_isolated/setup.bash
rosbag play --loop path/to/bag_file

• 确保替换path/to/bag_file为要播放的包文件的路径

• 现在数据正在播放并且网桥正在运行，结果如下

# Shell S:
. /opt/ros/ardent/setup.bash
# Or, if building ROS 2 from source:
# . <workspace-with-bridge>/install/setup.bash
ros2 topic list
ros2 topic echo /odom

% ros2 topic list
/clock
/image
/imu_data
/odom
/parameter_events

• 使用showimage工具查看从包中播放的图像

ros2 run image_tools showimage