I am trying to get a LD19 LiDAR sensor to work with a Raspberry Pi 4B and ros2 by following this guide: https://botland.de/img/art/inne/21991\_Instrukcja%20rozbudowy.pdf

Everything got installed without problem, but when I then try to launch the program I get the Error message in the title.

I have tried different versions of ros and ubuntu but I still get the same Error.

I also tried an external power supply, which also changed nothing.

What can I do?

Here is the launch command and the full response:

$ ros2 launch ldlidar\_stl\_ros2 ld19.launch.py

\[INFO\] \[launch\]: All log files can be found below /home/lennart/.ros/log/2026-04-05-16-37-12-930576-lennart-3912

\[INFO\] \[launch\]: Default logging verbosity is set to INFO

\[INFO\] \[ldlidar\_stl\_ros2\_node-1\]: process started with pid \[3915\]

\[INFO\] \[static\_transform\_publisher-2\]: process started with pid \[3916\]

\[static\_transform\_publisher-2\] \[WARN\] \[1775399833.454494608\] \[\]: Old-style arguments are deprecated; see --help for new-style arguments

\[ldlidar\_stl\_ros2\_node-1\] \[INFO\] \[1775399833.530358796\] \[LD19\]:  \[ldrobot\] SDK Pack Version is v2.3.0

\[ldlidar\_stl\_ros2\_node-1\] \[INFO\] \[1775399833.530750693\] \[LD19\]:  \[ldrobot\] <product\_name>: LDLiDAR\_LD19 ,<topic\_name>: scan ,<port\_name>: /dev/ttyUSB0 ,<frame\_id>: base\_laser

\[ldlidar\_stl\_ros2\_node-1\] \[INFO\] \[1775399833.530832690\] \[LD19\]: \[ldrobot\] <laser\_scan\_dir>: Counterclockwise,<enable\_angle\_crop\_func>: false,<angle\_crop\_min>: 135.000000,<angle\_crop\_max>: 225.000000

\[ldlidar\_stl\_ros2\_node-1\] \[INFO\] \[1775399833.542934901\] \[LD19\]:  \[ldrobot\] open LDLiDAR\_LD19 device /dev/ttyUSB0 success!

\[static\_transform\_publisher-2\] \[INFO\] \[1775399833.591116749\] \[base\_link\_to\_base\_laser\_ld19\]: Spinning until stopped - publishing transform

\[static\_transform\_publisher-2\] translation: ('0.000000', '0.000000', '0.180000')

\[static\_transform\_publisher-2\] rotation: ('0.000000', '0.000000', '0.000000', '1.000000')

\[static\_transform\_publisher-2\] from 'base\_link' to 'base\_laser'

\[ldlidar\_stl\_ros2\_node-1\] \[ERROR\] \[1775399834.656199294\] \[LD19\]: \[ldrobot\] lidar pub data is time out, please check lidar device

\[ERROR\] \[ldlidar\_stl\_ros2\_node-1\]: process has died \[pid 3915, exit code 1, cmd '/home/lennart/ldlidar\_ros2\_ws/install/ldlidar\_stl\_ros2/lib/ldlidar\_stl\_ros2/ldlidar\_stl\_ros2\_node --ros-args -r \_\_node:=LD19 --params-file /tmp/launch\_params\_afxbq\_nt --params-file /tmp/launch\_params\_ajkldc08 --params-file /tmp/launch\_params\_vgvgpbon --params-file /tmp/launch\_params\_u9\_wd68a --params-file /tmp/launch\_params\_yc35\_wki --params-file /tmp/launch\_params\_u\_k72th4 --params-file /tmp/launch\_params\_fib24ll2 --params-file /tmp/launch\_params\_cu3tiynl'\].

[ldrobot] lidar pub data is time out, please check lidar device