[RyanCahoon]

Originally Posted by Ether

:-) ... OK. Lets' do it that way.

Question1: In the video, is the positive X axis pointing to the left or to the right?

Judging by the coordinate values given in the second half of the video, I would say the positive X axis is to the right, positive Y axis is up.

I think I see where you're going with this though... in that the diagram showing angle theta as an acute angle doesn't match the angle that would be calculated from delta-x and delta-y in the world coordinate system.

So to answer your original question, I think at this point it's probably just worth noting that the video is meant to give an intuitive sense of how things work and the general types of formulae that will be needed instead of being mathematically rigorous.

My request for one of your odometry posts was meant to ask whether you already had a post somewhere that gave the correct mathematics, as it seems like something you might have covered before.