Programs can't detect T265 but viewer can in Jetson nano

[RonghaiHe]

Required Info
Camera Model	T265
Firmware Version	0.2.0.951
Operating System & Version	Ubuntu18.04
Kernel Version (Linux Only)	4.9.253
Platform	NVIDIA Jetson Nano
SDK Version	2.50.0
Language	python &C++
Segment	Robot

Issue Description

I connected T265 to Jetson Nano and I can start obtaining the tracking information in the realsense-viewer with Usb Type Descriptor: USB3.1. When I closed the viewer and tried running the python codes t265_samples.py in /librealsense/wrappers/python/examples, it showed that no devices connected.

Traceback (most recent call last):
  File "t265_example.py", line 21, in <module>
    pipe.start(cfg)
RuntimeError: No device connected

When I tried running the rs-pose, a compiled C++ program in /librealsense/build/examples/pose, it showed that:

RealSense error calling rs2_pipeline_wait_for_frames(pipe:0x559cc0d7b0):
    Frame didn't arrive within 15000

I entered rs-enumerate-devices -d and it showed the Device info as well as (outputs about the time are deleted):

Default streams:
(handle-libusb.h:100) failed to claim usb interface: 0, error: RS2_USB_STATUS_BUSY
(librealsense-exception.h:52) Unable to open device interface
(handle-libusb.h:100) failed to claim usb interface: 0, error: RS2_USB_STATUS_BUSY
(librealsense-exception.h:52) Unable to open device interface
(handle-libusb.h:100) failed to claim usb interface: 0, error: RS2_USB_STATUS_BUSY
(librealsense-exception.h:52) Unable to open device interface
RealSense error calling rs2_config_resolve(config:0x558a34ec00, pipe:0x558a34ccb0):

When I connected D435i with Jetson Nano in the same USB interface and run C++ programs and python codes, there's nothing wrong with them.

The installation steps are as below. I don't know whether it made a difference to this issue: At first, I use this way to install the RealSense SDK: Running pyrealsense2 on JetsonNano I also copied .so documents from /librealsense/build/wrappers/python to /usr/lib/pythn3/dist-packages Then I noticed librealsense/doc/installation_jetson.md and I just did "Getting started" because I thought that's enough.

In conclusion, I can obtain the information from T265 in the realsense-viewer but I can't do it by python codes or C++ programs.

[RonghaiHe]

I tried again a few days later and it worked. I connected to Jetson NX at first and it was failed again. But I retried and to my surprise, it worked! Thus, I connected to Jetson Nano and it also worked! I don't know why but I have no issue. Shall I close the issue or just open it until the reasons are found out?

[arjunpuninchittaya]

I am running into the same issue, was anything else done other than waiting? Does it cease to work every so often? Thanks!

[jyomk]

I'm trying to run the T265 camera for a tracking project. The camera is detected using lsusb, rs-enumerate-devices. Also, when running rs-pose, I see the coordinates. however, when I start a pipeline I get the following error message: RealSense error calling rs2_pipeline_start_with_config(pipe:0x55f0ab2e0e50, config:0x55f0ab2e1400) Has anyone faced this issue? Please let me know if you have any solution. Thanks!