Realsense error calling rs2_pipeline_start_with_config(pipe:0x55b26cd620, config:0x55b26b29a0): Couldn't resolve requests)

[meihe323]

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Required Info
Camera Model	{ D400 }
Firmware Version	(Open RealSense Viewer --> Click info)
Operating System & Version	Linux
Kernel Version (Linux Only)	(e.g. 4.14.13)
Platform	Raspberry Pi 4B 8GB
SDK Version	{ legacy / 2.<?>.<?> }
Language	{C/C#/labview/nodejs/opencv/pcl/python/unity }
Segment	{Robot/Smartphone/VR/AR/others }

Issue Description

<Describe your issue / question / feature request / etc..> Im working on a project about muticoptors landing on moving platform, and I choose the apriltags and D435i to get the pose of moving platform, but when I run the rs-pose-apriltag examples programs, I got a message as title shows. I am sure that the cable is fine and realsense-viewer is working perfectly. I wonder what's wrong with the example programs? What should I do to get the pose of moving platform through D435i and designed apriltag codes?

[MartyG-RealSense]

Hi @meihe323 The example program rs-pose-apriltag is for the RealSense T265 Tracking Camera model only and will not work with other RealSense camera models such as D435i.

A different type of image tag called ArUco is better supported for RealSense 400 Series camera models such as D435i. An example of such a program is at the link below.

https://github.com/Jphartogi/ipa_marker_detection

There is also an ArUco tutorial for OpenCV with Python code here:

https://www.learnopencv.com/augmented-reality-using-aruco-markers-in-opencv-c-python/

Several years ago, a developer created a RealSense ArUco tracker in the Unity engine that used the OpenCV for Unity software.

https://github.com/ajingu/RealSense#aruco https://assetstore.unity.com/packages/tools/integration/opencv-for-unity-21088#description

A company called Everdrone demonstrated a RealSense-equipped medical drone that used image tags placed on the ground for landing guidance.

https://www.intelrealsense.com/everdrone/

[MartyG-RealSense]

Hi @meihe323 Do you require further assistance with this case, please? Thanks!

[MartyG-RealSense]

Case closed due to no further comments received.

[nirmalsnair]

I was getting the same error. For me it was the USB cable. Replacing it with a better USB-C to USB-C cable solved the error.

For more info, please read the 'Check your cables' section at the bottom of this page: https://nomagic.ai/tricks-and-tips-of-using-realsense-d400-series/

[MartyG-RealSense]

Thanks so much @nirmalsnair for sharing the experience of what worked for you in your situation!