Search code examples
algorithmexcelrounded-cornersvba

radius between 2 arcs

Looking for an algorithm to calculate the intersection points of the corner radius between 2 arcs. Intersection point, centres and radius of both arcs are known. Radius of corner rad is also known.

enter image description here

Solution

  • Fairly easy: the center of the fillet is located a distance r from both arcs, hence on circles of radii r'-r and r"-r, with the same centers. Just compute the intersection of these circles.

    enter image description here

    The tangency points are located on the lines that join the centers, hence you readily obtain the delimiting angles.