EuRoC Forum

[bridos]

Hello, are we allowed/supposed to move the pan tilt camera unit? If so which is the topic responsible for the camera position that we can interact with?
Thank you very much for your time.

[Peter Lehner]

Hello, are we allowed/supposed to move the pan tilt camera unit? If so which is the topic responsible for the camera position that we can interact with?

Yes you are definitely encouraged to move the pan-tilt unit. The pan-tilt unit can be moved like any system joint by specifying the joints with the strings "cam_pan" and "cam_tilt" in the ros movement services (move_along_joint_path, set_servo_target). For more information see the technical annex Sections 2.2.3 and 2.5.2.

Best,
Peter

[bridos]

Thank you very much for your time. I have encountered an error while trying to move the camera:
[ERROR] [1413974402.088627696, 5.025000000]: move_along_joint_path: exception caught: Path requrres minimum one step
what am I doing wrong?

[Peter Lehner]

I have encountered an error while trying to move the camera:
[ERROR] [1413974402.088627696, 5.025000000]: move_along_joint_path: exception caught: Path requrres minimum one step
what am I doing wrong?

The Exception indicates that the path field which you are passing inside the move_along_joint_path service request is empty (contains no configurations).

Here is a snippet on how you would move the cameras with the python demo system:

Code: Select all

# Create a camera configuration of zero values
camera_configuration = Configuration(q = [0.0] * len(system.cam_joints))
# Create a path (list of configurations) which contains the new configuration
path = [camera_configuration]
# Move the cameras with the newly created path
system.move(path, system.cam_joints)