cv_perception

This package is based on ROS-melodic with Ubuntu 18.04.

1. Usage

1.1 Basic usage

# Launch all nodes
roslaunch lfi_launch all.launch

# Launch camera nodes
roslaunch lfi_launch camera.launch

# Launch GPS node
roslaunch lfi_launch gps.launch

# Launch data recorder node
roslaunch data_collector dumpper.launch

Robot vision configuration file is at:

cv_perception/config/lawn_mover.json

Please remember to set the camera name(B601A/B601B/601C) in above configure file to get the right calibration. The camera name can be found at the bottom of the camera.

All the dataset recorded in Nanjing, China were using B601C, and other two cameras has shipped to US.

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1.2 Change camera record resolution

• Edit the camera_record_res in config/lawn_mover.json

Please note that our previous dataset was recorded with 3840 x 2160, and currently the camera record resolution has set to 1280 x 760. So if you want to switch between replay and real time launch mode, please remember to modify this paramter.

"camera_record_res" : [1280, 720]

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1.3 Replay recorded dataset

# single play
rosbag play <dataset_name>

# loop mode
rosbag play -l <dataset_name>

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1.4 Show panoramic image

# opencv window
rosrun image_wrapper display_image

# rostopic
rosrun image_wrapper publish_topic

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1.5 Record data

Set the <function_dump> to 1 in config/lawn_mover.json, and dump_path to where you would like to store the data. You can also set which sensor to be recorded and its paramters such as resolution.

"dump_path" : "/data/log3/",

"camera_dump_raw":1,
"camera_dump_raw_width":1280,
"camera_dump_raw_height":760,

"camera_dump_pano": 1,
"camera_dump_pano_width":793,
"camera_dump_pano_height":367,

"imu_dump" : 1,
"gps_dump" : 1

2. Published Topics

Topic Name	Msg Type	Function	Comment
/IMU_data	sensor_msgs/Imu	External IMU sensor data
/PowerVoltage	std_msgs/Float32	Battery Voltage
/mobile_base/sensors/imu_data	sensor_msgs/Imu	Stm32 onboard IMU sensor data
/odom	nav_msgs/Odometry	Chassis Odometry data
/ublox_gps/fix	sensor_msgs/NavSatFix	GPS location data
/ublox_gps/navheading	sensor_msgs/Imu	GPS IMU data
/ublox_gps/navsat	ublox_msgs/NavSAT	GPS localization method
/usb_cam/camera_info	sensor_msgs/CameraInfo	Camera raw infomation
/usb_cam/image_raw	sensor_msgs/Image	Camera raw image data
/camera/wimage	sensor_msgs/Image	Camera unwrap image data

3. Nodes Introduction

2.1 image_wrapper

Provoding panoramic image unwrap function.

• display_image will pop out an opencv style window with the unwrap image.
• publish_topic will establish a publisher topic at /camera/wimage.

Required configure JSON file:

cv_perception/config/<camera_name>.json

If you are viewing recorded data with 3840x2160, it's highly recommended to set the "display_ratio" to 5, otherwise please do not change anything.

The default recording resolution will be 1280 x 720, and the unwrap image's resolution will be 793 x 367.

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2.2 web_video_server

This node could start RTMP streaming and provide a web page to view both the original camera image or the unwrap panoramic image. This node was launched by camera.launch.

The default web address is http://<device_ip>:8080.

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2.3 rtcm

This node could output the ntrip network RTK localization data to a specific serial port. The configure file is at

cv_perception/lfi_launch/gps.launch

You can replace the content of the in paramter with your own local ntrip services.

This node will also launch the ublox_gps moudle, which could provide the robot GPS infomation.

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2.4 data_collector

This node could record image, IMU, and GPS data to your specific folder.