Cannot get frames from multiple D415 cameras with pyrealsense2 - no problems in realsense-viewer

[anthnyprschka]

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Required Info
Camera Model	D415
Firmware Version	05.12.14.50
Operating System & Version	Ubuntu 20
Platform	PC
Language	python

Issue Description

I am trying to view frames from multiple D415 cameras using a script provided in #1735.

But the script fails with the following error:

Traceback (most recent call last):
  File "test_multiple_rs.py", line 44, in <module>
    frames_2 = pipeline_2.wait_for_frames()
RuntimeError: Frame didn't arrive within 5000

Viewing the cameras in realsense-viewer simultaneously works.

This problem happens on Ubuntu as well as macOS.

Update: Could have sth to do with the cams being connected thru USB 2.0 repeater cables, cuz seems to work if cams are connected with the USB cables that were shipped with the cams.

Update: pipeline_2.wait_for_frames(10000) seems to fix it

[MartyG-RealSense]

Hi @anthnyprschka It is excellent to hear that you found a fix that seems to have resolved your problem.

You may also be interested in the Python multiple camera project in the link below that was created by a RealSense user

https://github.com/ivomarvan/samples_and_experiments/tree/master/Multiple_realsense_cameras

I would also recommend not exceeding a maximum distance of 20 meters with active repeater extension cables, and using the official 1 meter cable supplied with the camera when performing firmware updates instead of doing so with an active repeater cable.

If you need to extend to longer distances (up to 100 meters) then ethernet networking cabling is recommendable, or fiber optic cable like the solution provided by the company Newnex (see the links below).

https://www.newnex.com/realsense-3d-camera-connectivity.php
https://youtube.com/watch?v=GLQgR1jT04M

[MartyG-RealSense]

Hi @anthnyprschka Do you require further assistance with this case, please? Thanks!

[MartyG-RealSense]

Case closed due to no further comments received.