topic Re: I could not use get the pose_frame from my realsense d435i in Items with no label

I could not use get the pose_frame from my realsense d435i

振夏 — Sat, 20 Apr 2019 16:40:08 GMT

In my project , I need to get the pose information from the d435i; But I found that I could get that in default settings.I use the following code which from the librealsense-master to test why the pose information can not be exported.

// License: Apache 2.0. See LICENSE file in root directory.
// Copyright(c) 2019 Intel Corporation. All Rights Reserved.
#include <librealsense2/rs.hpp>
#include <iostream>
#include <iomanip>
 
int main(int argc, char * argv[]) try
{
	// Declare RealSense pipeline, encapsulating the actual device and sensors
	rs2::pipeline pipe;
	// Create a configuration for configuring the pipeline with a non default profile
	rs2::config cfg;
	// Add pose stream
	cfg.enable_stream(RS2_STREAM_POSE, RS2_FORMAT_6DOF);
	// Start pipeline with chosen configuration
	pipe.start(cfg);
 
	// Main loop
	while (true)
	{
		// Wait for the next set of frames from the camera
		auto frames = pipe.wait_for_frames();
		// Get a frame from the pose stream
		auto f = frames.first_or_default(RS2_STREAM_POSE);
		// Cast the frame to pose_frame and get its data
		auto pose_data = f.as<rs2::pose_frame>().get_pose_data();
 
		// Print the x, y, z values of the translation, relative to initial position
		std::cout << "\r" << "Device Position: " << std::setprecision(3) << std::fixed << pose_data.translation.x << " " <<
			pose_data.translation.y << " " << pose_data.translation.z << " (meters)";
	}
 
	return EXIT_SUCCESS;
}
catch (const rs2::error & e)
{
	std::cerr << "RealSense error calling " << e.get_failed_function() << "(" << e.get_failed_args() << "):\n    " << e.what() << std::endl;
	return EXIT_FAILURE;
}
catch (const std::exception& e)
{
	std::cerr << e.what() << std::endl;
	return EXIT_FAILURE;
}

The result tells that the stream of pose can not be opened:

Could you give me a solution for this question.

Re: I could not use get the pose_frame from my realsense d435i

振夏 — Sat, 20 Apr 2019 16:44:05 GMT

Sorry, I forget to introduce the platform. I use this camera at Windows 10 ,64bit.

Re: I could not use get the pose_frame from my realsense d435i

MartyG — Sat, 20 Apr 2019 21:22:14 GMT

I hope the link below will be of use to you.

https://forums.intel.com/s/question/0D70P000006GEZUSA4

The RealSense T265 has the same IMU component as the D435i. The T265 can provide 6DOF pose though because unlike the D435i, "the VPU employed with T265 is capable of fusing inertial and video sensors to produce a reliable and persistent six degrees of freedom (6DOF) pose, offloading the CPU-intensive calculations from the host PC".

https://www.intelrealsense.com/how-to-getting-imu-data-from-d435i-and-t265/

Re: I could not use get the pose_frame from my realsense d435i

振夏 — Sat, 20 Apr 2019 21:48:52 GMT

Thank you for your reply. I have read the link and think it is useful .But it's not for my question. The data I want to get is the angular-velocity , accelerated velocity and the pose of the camera. All these data are contained in the class "rs2_pose", and the "rs2::pose_frame" have the function to get the "rs2_pose" of current frame , that's why I show the code. When I add the stream of pose_frame, the camera tell me that there is somethings wrong when open the stream. But thank you all the same!

Re: I could not use get the pose_frame from my realsense d435i

MartyG — Sat, 20 Apr 2019 22:20:17 GMT

The subject of RS2_STREAM_POSE is discussed here:

https://github.com/IntelRealSense/librealsense/issues/3070

The pose stream was added to the SDK as a feature for the T265 Tracking Camera model. The SDK developers hope to make the pose stream accessible to D435i in the future via RealSense SLAM. The reasons why RealSense SLAM development is difficult for D435i are provided by Dorodnic the RealSense SDK Manager in this comment from the discussion in the link above.

https://github.com/IntelRealSense/librealsense/issues/3070#issuecomment-454689295

Re: I could not use get the pose_frame from my realsense d435i

振夏 — Sat, 20 Apr 2019 22:46:01 GMT

Thank you for quick response. Maybe I choose the wrong way to get the data. I choose the pose_frame only because the class "rs2_pose" contains these data . But I have seen that others have got these data on ROS , Ubuntu. And I think the angular-velocity , accelerated velocity and the orentation of the camera can be supported by the imu and do not need any calculation. Maybe I need choose some other way to get these data. Thanks a lot!

Re: I could not use get the pose_frame from my realsense d435i

MartyG — Sat, 20 Apr 2019 23:41:54 GMT

I'm very glad I could be of help. :)