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  3. AprilTag Localization not affecting static coordinate system

AprilTag Localization not affecting static coordinate system

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  • C Offline
    C Offline
    casez
    wrote on last edited by
    #1

    I am trying to get AprilTag localization working on the Starling 2 drone but I cannot get the fixed coordinate system to change based on the apriltag. I am able to detect it correctly, but relocalization does not work.

    Here are relevant configuration files, I mainly followed the example link.

    voxl-tag-detector.conf

    /**
     * This file contains configuration parameters for voxl-tag-detector.
     * You can specify up to 3 cameras to do detection on simultaneously.
     * For the stereo camera pair, only the left camera is used.
     */
    {
    	"detector_0":	{
    		"enable":	true,
    		"input_pipe":	"tracking_front",
    		"en_fast_mode":	true,
    		"n_threads":	1,
    		"en_undistortion":	true,
    		"undistort_scale":	0.600000023841858,
    		"overlay_name":	"tracking_tag_overlay",
    		"lens_cal_file":	"/data/modalai/opencv_tracking_front_intrinsics.yml",
    		"skip_n_frames":	5
    	}
    }
    

    tag_locations.conf

    {
            "locations":    [{
                            "id":   0,
                            "name": "landing-pad",
                            "loc_type":     "fixed",
                            "size_m":       0.17145,
                            "T_tag_wrt_fixed":      [0, 0, 0],
                            "R_tag_to_fixed":       [[0, -1, 0], [1, 0, 0], [0, 0, 1]]
                    }],
            "default_size_m": 0.17145 //  0.40000000596046448
    }
    

    in voxl-vision-hub.conf I have

    "en_tag_fixed_frame": true,
    "en_transform_mavlink_pos_setpoints_from_fixed_frame": true
    

    When I run

    voxl-vision-hub -l
    

    I am able to see the tags position update as it moves.

    When I run

    voxl-vision-hub -p
    

    I can see the local_wrt_fixed change when the drone moves, but not when the tag moves. I would expect the local_wrt_fixed to also change with the tag moving since it is set to be [0,0,0].

    I also often get a "WARNING, apriltag roll/pitch out of bounds", which appears to be a common issue.

    Is there a configuration error I am missing or some way I can get the relocalization system to work?

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