# Determining Orientation of a Robot Relative to a Line on Table

I am currently busy with a robot that needs to obtain it's orientation relative to a line seen by a camera. At the moment, I am using Hough lines to obtain a gradient for the line, but the gradient obtained is not the same as the orientation of the robot relative to the line. In other words, if I place the line 45 degrees Infront of the robot, the returned gradient of the line is not 1 (for a 45 degree line). I'm guessing this is due to the line being in a different plane to that of the camera image. The camera is tilted 15 degrees down, but can be made to be exactly vertical.

How would I calculate the orientation of the robot relative to the line from the lines obtained in the camera? I have attached an image to help aid in my explanation.

I would like to know if using the rotation and translation matrix of cameras would help solve this problem too.

• I have been trying to use the cameras intrinsic and extrinsic parameters, as well as the rotation and translation matrix to solve this issue, however, since the robot is always moving, the rotation and translation matrices are always changing. Can anyone assist? Mar 18, 2020 at 13:14