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Read and visualize your robot sensors
Description: Read and visualize your robot sensorsTutorial Level: BEGINNER
Next Tutorial: Command you robot with simple motion commands
This tutorial will cover the steps needed in order to read and visualize your robot's sensors.
Contents
RGB color cameras
The robot's cameras are launched using the usb_cam package. Each camera stream is published through a sensor_msgs/Image message.
The topic name for the main raw data is: <camera_name>/image_raw. For example, the robot front camera topic is: front_camera/image_raw.
To view the camera stream from the rqt rqt_image_view plugin, select from the rqt upper menu:
Plugins -> Visualization -> Image view
and select the image you want to view from the drop down box.
Laser scanner
The laser scanner driver node is hokuyo_node. The data is published through a sensor_msgs/LaserScan message under the topic /scan.
To view the camera stream from the rqt rqt_rviz plugin, select from the rqt upper menu:
Plugins -> Visualization -> Rviz
To add the laserscan visualization to Rviz, press the Add button on the bottom of the left Rviz displays list window, select LaserScan under rviz folder, and press OK on the bottom of the window (Add -> LaserScan -> OK).
Now, you will be able to see that LaserScan property was added to the left Rviz displays list window. Press the small arrow on the left of the LaserScan property to expand its properties. For Topic property select /scan. Notice: you will not be able to see the LaserScan visualization in Rviz, unless the robot is in front of an object.
Ultrasonic Range Finders (URF)
The range finders data is published through a sensor_msgs/Range message under the topic /URF/<sensor_name>.
Most robots have 3 rangers mounted on the left, right and rear of the mobile base and the topics are: /URF/left/, /URF/right and /URF/rear accordingly.
To view the camera stream from the rqt rqt_rviz plugin, select from the rqt upper menu:
Plugins -> Visualization -> Rviz
To add the URF visualization to Rviz, press the Add button on the bottom of the left Rviz displays list window, select Range under rviz folder, and press OK on the bottom of the window (Add -> Range -> OK).
RGB-D depth cameras
Kinect 2
We use the following collection of tools and libraries for a ROS Interface to the Kinect One (Kinect v2):
https://github.com/code-iai/iai_kinect2
See https://github.com/code-iai/iai_kinect2/tree/master/kinect2_bridge for details on topics names and types.
RealSense F200
Asus Xtion Pro Live
To add the depth camera visualization to Rviz, press the Add button on the bottom of the left Rviz displays list window, select PointCloud2 under rviz folder, and press OK on the bottom of the window (Add -> PointCloud2 -> OK).
GPS
The GPS data is published through a sensor_msgs/NavSatFix message under the topic /GPS/fix.
Inertial Measurement Unit (IMU)
The IMU data is published through a sensor_msgs/Imu message under the topic /IMU/data.
The Magnetometer data is published through a geometry_msgs/Vector3Stamped message under the topic /IMU/magnetic.
