Wednesday, August 1, 2012

Fabricating Articulated Characters from Skinned Meshes

Given a skinned mesh (a), we estimate (b) a fabricatable articulated character with (c) internal joints of hinge and ball-and-socket
type. (d,e) Final 3D printed characters (transparent material) have durable joints with a frictional design for character posing.

"Articulated deformable characters are widespread in computer animation. Unfortunately, we lack methods for their automatic fabrication using modern additive manufacturing (AM) technologies. We propose a method that takes a skinned mesh as input, then estimates a fabricatable single-material model that approximates the 3D kinematics of the corresponding virtual articulated character in a piecewise linear manner. We first extract a set of potential joint locations. From this set, together with optional, user-specified range constraints, we then estimate mechanical friction joints that satisfy inter-joint non-penetration and other fabrication constraints. To avoid brittle joint designs, we place joint centers on an approximate medial axis representation of the input geometry, and maximize each joint’s minimal cross-sectional area. We provide several demonstrations, manufactured as single, assembled pieces using 3D printers."

Authors; Moritz Bächer, Bernd Bickel, Doug L. James, Hanspeter Pfister.

Adding a '3D print' button to animation software