I have been thinking about the difficulty involved in robotic movement, and the fact that the complexity involved is beyond the imagination of very nearly everyone.

First of all, though, you have to understand cartesian coordinates, because that’s where it all starts.

The following is a drawing of a machine, showing it’s x, y, and z axis. it can move in a straight line in any of those axes, and by controlling speed, distance, and direction, it can interpolate any shape that can be generated in space, theoretically.

Each axis has an origin point, and movement in one direction from that origin is positive, and the other direction negative. This is the basis of nearly all machining. Once you understand this, everything else just builds on it.