Hallo, kingkaisai2,Originally Posted by kingkaisai2
you want to calculate the shortest distance between 2 straight lines in , which are not equal nor parallel nor intersecting. (The German word is "windschief", literally translated it means crooked. But I don't believe that this is the appropriate expression in English).
The equation of a line in 3D is: , where the vector s determines the startingpoint S and the vector u the direction of the line.
The old tunnel is described by:
and the new tunnel runs on this line:
These lines are not parallel and they don't intersect. So the shortest distance is calculated by:
Plug in the values you know: