(Georgia Institute of Technology, 2006-08)
Johnston, Scott R.; Rosen, David W.; Reed, Marques; Wang, Hongqing Vincent
A unit truss finite element analysis method allowing non-linear deformation is employed to analyze a unit cell comprised of n3 octet-truss structures for their stiffness and displacement compared to their relative density under loading. Axial, bending, shearing, and torsion effects are included in the analysis for each strut in the octet-truss structure which is then related to the mesostructure level (unit cell). The versatility of additive manufacturing allows for the fabrication of these complex unit cell truss structures which can be used as building blocks for macro-scale geometries. The finite element calculations are compared to experimental results for samples manufactured on a Stereolithography Apparatus (SLA) out of a standard resin.
(Georgia Institute of Technology, 2006-07)
Rosen, David W.; Johnston, Scott R.; Reed, Marques
The primary goal is to design parts with lattice mesostructure and demonstrate that they have
better structural and/or compliance performance, per weight, than parts with bulk material,
foams, or other mesostructured approaches. Mesostructure refers to features within a part that
have sizes between micro and macro-scales, for example, small truss structures, honeycombs,
and foams. The versatility of additive manufacturing allows for the fabrication of these complex
unit cell lattice structures which can be used as building blocks for macro-scale geometries. A
method and software system have been developed to synthesize lattice mesostructure parts and
compliant mechanisms in 2D and 3D. Underlying the synthesis method is a new analytical
model of unit lattices, used to compose larger structures. Axial, bending, shearing, and torsion
effects are included in the analysis for each strut in the lattice structure which is then related to
the mesostructure level (unit cell). A unit lattice finite element analysis method allowing nonlinear
deformation is employed to analyze a unit cell comprised of n[3] unit structures for their
stiffness and displacement compared to their relative density under loading. Aerospace and
biomedical applications are demonstrated.