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Camera Calibration on Nao Robot

asked 2011-08-22 01:19:11 -0500

Shamma gravatar image

updated 2011-08-23 00:51:01 -0500

mjcarroll gravatar image

hello there,

I would like to use Camera calibration that is already implemented in ROS, to get the images of my robot Nao, and then use the information of the calibration to calculate the real world coordinate..

I don't know how would I do it with the robot camera, they have example of Monocular Camera...

Any help?


here what I would like to do, and I thought camera calibration would do it for me:

I want to define a zero point in the environment or what they call it a reference point in which that point will have (0,0,0) values I want to take some picture of the environment where I have objects set on some places I want to measure the coordinates of the object in real life "I will do that manually with a meter" I want to feed a method "I don't know what method" with these values so it will be able to compare between real life coordinate and pixel coordinate anytime it needs to assume the real life coordinate any idea how can I do that ?



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Shamma, Please follow the site guidelines. Please use comments or edits to add information to your original question, do not use answers as comments.
mjcarroll gravatar image mjcarroll  ( 2011-08-23 00:50:30 -0500 )edit

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answered 2011-08-22 06:46:56 -0500

AHornung gravatar image

The Nao's cameras work just like any other monocular camera. But what do you mean with "calculate real world coordinate"? Without any additional information (like a ground plane) you cannot derive 3D coordinates from 2D image coordinates. For that you need stereo vision which the Nao's camera's can't provide. Monocular SLAM (visual odometry, structure from motion, ...) could be a solution for that, but is a research topic of its own.

You can still calibrate your Nao's cameras just like any other webcam, it only lacks a proper ROS-enabled driver that outputs the correct topics for the automatic calibration. I would suggest to record 10 static frames with the checkerboard in various positions and then feed them into the OpenCV camera calibration.

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Asked: 2011-08-22 01:19:11 -0500

Seen: 1,156 times

Last updated: Aug 23 '11