module 'crtk' has no attribute 'ral'

[MichaelWangGo]

Hi, thank you for the opensource!

When I run python dvrk_arm_test.py, I got the error: 'module 'crtk' has no attribute 'ral''.

How can I solve it?

Thank you!

[adeguet1]

You likely have an older version of CRTK python in your workspace. Make sure you use matching versions. I would recommend to use VCS and the VCS files provided along the dVRK. See https://github.com/jhu-saw/vcs Can you go in the source directories for src/crtk/crtk_python_client and src/dvrk/dvrk_python and run `git describe` in each repository? That would tell us which versions you are using. Anton On Jun 20, 2025, at 11:17, Xu Wang ***@***.***> wrote: External Email - Use Caution [https://avatars.githubusercontent.com/u/59171959?s=20&v=4]MichaelWangGo created an issue (jhu-dvrk/dvrk_python#4)<#4> Hi, thank you for the opensource! When I run python dvrk_arm_test.py, I got the error: 'module 'crtk' has no attribute 'ral''. How can I solve it? Thank you! — Reply to this email directly, view it on GitHub<#4>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AAIRP424P6TUG5EZJ7KBNCT3EQQ2HAVCNFSM6AAAAAB7YSMRTWVHI2DSMVQWIX3LMV43ASLTON2WKOZTGE3DGNRXGU4DKMY>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[MichaelWangGo]

Thank you for the reply @adeguet1

We have solved the problem of 'ral' using vcs. The versions of src/crtk/crtk_python_client and src/dvrk/dvrk_python are 1.3.1 and 2.3.0, respectively.

Another question is as follows:

davinci@ucl:~/catkin_ws_xuwang/src/cisst-saw/sawIntuitiveResearchKit/share/ucl-CBH-dVRK/ethernet$ rosrun dvrk_python dvrk_arm_test.py -a PSM1
configuring dvrk_arm_test for PSM1
Traceback (most recent call last):
File "/home/davinci/catkin_ws_xuwang/src/dvrk/dvrk_python/scripts/dvrk_arm_test.py", line 269, in
ral.spin_and_execute(application.run)
File "/home/davinci/catkin_ws_xuwang/src/crtk/crtk_python_client/src/crtk/ral_ros1.py", line 92, in spin_and_execute
function(*arguments)
File "/home/davinci/catkin_ws_xuwang/src/dvrk/dvrk_python/scripts/dvrk_arm_test.py", line 247, in run
self.home()
File "/home/davinci/catkin_ws_xuwang/src/dvrk/dvrk_python/scripts/dvrk_arm_test.py", line 45, in home
self.arm.check_connections()
File "/home/davinci/catkin_ws_xuwang/src/dvrk/dvrk_python/src/dvrk/arm.py", line 107, in check_connections
self.__ral.check_connections(timeout)
File "/home/davinci/catkin_ws_xuwang/src/crtk/crtk_python_client/src/crtk/ral_ros1.py", line 184, in check_connections
self._check_connections(start_time, timeout_duration, check_children)
File "/home/davinci/catkin_ws_xuwang/src/crtk/crtk_python_client/src/crtk/ral_ros1.py", line 143, in _check_connections
child._check_connections(start_time, timeout_duration, check_children)
File "/home/davinci/catkin_ws_xuwang/src/crtk/crtk_python_client/src/crtk/ral_ros1.py", line 168, in _check_connections
raise TimeoutError(err_msg.format(connected_pub_count))
TimeoutError: Timed out waiting for publisher/subscriber connections to establish
Publishers: 0 connected, 1 not connected
not connected: [/PSM1/spatial/servo_cf]
Subscribers: 0 connected, 2 not connected
not connected: [/PSM1/spatial/measured_cf, /PSM1/spatial/jacobian]

[adeguet1]

the check_connections method is used to make sure the publishers and subscribers in the Python scripts have corresponding subscribers and publishers. We use this to make sure all the corresponding topics exist. This has been quite useful when users provide the incorrect namespace (e.g. PSM1 vs PSM2). The drawback is that you need to make sure the main dVRK node (dvrk_console_json) is running before launching the dvrk_arm_test script. You can check that all the topics are "live" using rostopic list before starting dvrk_arm_test