Are you sure that your RPlidar model is a3 and that the serial_baudrate in your launch file is 256000? If you have model a2, then run rplidar.launch launch file, where serial_baudrate param is equal 115200:
roslaunch rplidar_ros rplidar.launch
Please, let me know about it. If you have any questions/troubles, do not hesitate to ask.
I’ve been using setting for a3 lidar with serial_baudrate=256000 for a while before the suddenly fail.
I will try to see if rplidar.launch works. At the same time, should I also try to update the rplidar_ros pakcage as @ Laschoking mentioned above (I am now wokring in ROS Melodic)?
I found I made a mistake about my robot model, it should be Rosbot2.0 Pro, so the lidar should be a3, and serial_baudrate=256000
Thanks for Rosbot 2.0 rplidar failed - #2 by Laschoking! I updated the rplidar_ros package, and the lidar now can be launched correctly, here is the logs after roslaunch rplidar_ros rplidar_a3.launch:
... logging to /home/husarion/.ros/log/78486784-f362-11ec-9ca6-000c297f8939/roslaunch-husarion-5208.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.
started roslaunch server http://192.168.28.135:42665/
SUMMARY
========
PARAMETERS
* /rosdistro: melodic
* /rosversion: 1.14.10
* /rplidarNode/angle_compensate: True
* /rplidarNode/frame_id: laser
* /rplidarNode/inverted: False
* /rplidarNode/scan_mode: Sensitivity
* /rplidarNode/serial_baudrate: 256000
* /rplidarNode/serial_port: /dev/ttyUSB0
NODES
/
rplidarNode (rplidar_ros/rplidarNode)
ROS_MASTER_URI=http://192.168.28.197:11311
process[rplidarNode-1]: started with pid [5389]
[ INFO] [1656043936.090754171]: RPLIDAR running on ROS package rplidar_ros, SDK Version:2.0.0
[ INFO] [1656043936.316347205]: RPLIDAR S/N: AFED9A87C5E392D2A5E492F83F38316C
[ INFO] [1656043936.316490961]: Firmware Ver: 1.27
[ INFO] [1656043936.316543196]: Hardware Rev: 6
[ INFO] [1656043936.367915075]: RPLidar health status : OK.
[ INFO] [1656043936.681688088]: current scan mode: Sensitivity, sample rate: 16 Khz, max_distance: 25.0 m, scan frequency:10.0 Hz,
However, the big problem still exists, I can not get any data from topic /scan:
Hi,
My initial guess is that sensitive mode may be causing some problems. Have you tried running in standard mode? Please, try to use this parameter in your launch file:
I tried the Standard mode as your suggested, but still no reponse to rostopic echo /scan.
After that, I tried to open the top cover to see if any cable connection broke. Then I got failure every time I launched rplidar_a3.launch even I closed the top cover back. Here is the log:
... logging to /home/husarion/.ros/log/1ee9796c-f5ba-11ec-9ca6-000c297f8939/roslaunch-husarion-4910.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.
started roslaunch server http://192.168.28.135:38911/
SUMMARY
========
PARAMETERS
* /rosdistro: melodic
* /rosversion: 1.14.10
* /rplidarNode/angle_compensate: True
* /rplidarNode/frame_id: laser
* /rplidarNode/inverted: False
* /rplidarNode/scan_mode: Standard
* /rplidarNode/serial_baudrate: 256000
* /rplidarNode/serial_port: /dev/ttyUSB0
NODES
/
rplidarNode (rplidar_ros/rplidarNode)
ROS_MASTER_URI=http://192.168.28.239:11311
process[rplidarNode-1]: started with pid [5131]
[ INFO] [1656295172.582627714]: RPLIDAR running on ROS package rplidar_ros, SDK Version:2.0.0
[ERROR] [1656295176.646174212]: Error, operation time out. RESULT_OPERATION_TIMEOUT!
[rplidarNode-1] process has died [pid 5131, exit code 255, cmd /home/husarion/husarion_ws/devel/lib/rplidar_ros/rplidarNode __name:=rplidarNode __log:=/home/husarion/.ros/log/1ee9796c-f5ba-11ec-9ca6-000c297f8939/rplidarNode-1.log].
log file: /home/husarion/.ros/log/1ee9796c-f5ba-11ec-9ca6-000c297f8939/rplidarNode-1*.log
all processes on machine have died, roslaunch will exit
shutting down processing monitor...
... shutting down processing monitor complete
done
I doubt if there is any problem in the connection from the lidar to the mainboard? Is there any way to make a check?
Please note that unauthorized opening of the robot case may result in loss of warranty.
To make sure it is not a software problem, please upload the latest Ubuntu image. If this does not help, please make sure the USB cable is working. If this does not help, it may be a hardware failure and you will need to replace your RPlidar.