Accumulated error during mapping

[Mahroo]

Dear Bernd, 

I'm running the tagslam to create a map of the environment (finding the pose of other tags given one known pose, only the pose of tag_5 is known). I ran the sync_and_detect first on the bag file, it was able to detect the apriltags. 

Then, I ran the tagslam on the output bag file of the sync_and_detect and I used rviz to visualize it, as shown in the figure below, the tags have the correct orientation but the poses are such that they have an accumulated error.

 

The first right tag is tag_5. 

I was wondering what could be the potential problem here and if there is a solution to fix that. The tagslam.yaml file is also attached. 

Best, 

Mahroo

[Bernd Pfrommer]

This looks very much like a bad intrinsic camera calibration file. Please post your cameras.yaml and say how you got the parameters for that.

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[Mahroo]

I used the openCV, having a checkboard to find calibration parameters. I attached the camera.yaml file.

[Bernd Pfrommer]

Usually the image center is close to 1/2 the width and 1/2 the height of the sensor (in pixels). In your case that should be (820, 616) but you have (587, 818). Can you check that

this line:

intrinsics: [1260.68429,1259.495486,587.13645838,817.21166]

is correct?

Could it be that the last two elements (cx, cy) should be switched around?