New Design Paradigms for
3D Printing
Krishnan Suresh
Associate Professor
Mechanical Engineering
CAD
SketchPad (MIT; 1963)
CAD: Underlying Philosophy
Influenced by traditional manufacturing
Controlled Complexity
3D Printing: Complexity is Free
Simple vs Complex
3D Printing
Geometric complexity is free
Controlled Complexity
Why Complexity?
Why design complex parts?
- Aesthetics
- Optimal
- Assembly-free
(3ders.com)
(mmsonline.com)
(bathsheba.com)
Optimal Design & Complexity
?
Stronger and lighter
(but more complex)
(3ders.com)
How to design such optimal parts?
Optimal Designs ~ Complex & Beautiful
“For the first time, our capacity to manufacture has
exceeded our capacity to design”
- Opening remark, 2013 ISAT/DARPA Workshop
Conventional CAD?
Example
Remove material, but keep it stiff!
A B
?
Visualize in 3-D
Idea!
Idea!!
Idea!!
Level Set
2D Example
PareTO
Software: www.ersl.wisc.edu
Michell Truss
Optimal
&
Beautiful
Topology Optimization (3D)
60% weight 50% weight
16
6% weight
Hook Design
• Strong
• Lite
• Controlled complexity
Geometric complexity is free
New design tools
for 3d printing
will emerge
Simulation Questions
Conventional FEA:
Incapable!
Can I print?
Will it break?
Optimal Design
Design
Space
Finite Element Analysis
(FEA)
Optimal?
Change
Topology
No
100’s of iterations!
20
Conventional FEA: Incredibly slow!
Optimal Design
Size
Optistruct
Intel Xeon, 12
core, 92 GB
(180,60,30) 20 hours
New Simulation Methods
for
High Performance Computing
CPU vs. GPU
Cache
RAM
GPU
Memory
50~1000 GFLOP
GPUCPU
10~50
GFLOP
(1~12 cores) (100~2000 cores)
GPU
Off-the-shelf PCI hardware ($100 - $500)
Vendors: NVidia, ATI,
Trends in Computing
Computing Speed Memory Speed
Memory starved computation
Takes more time to fetch 2 numbers than to multiply
(Brodtkorb 13)
New simulation tools
for 3d printing
will emerge
Optimal Designs
PareTO
Intel i7, 8
cores, 8 GB
42 mins
Size
Optistruct
Intel Xeon, 12
core, 92 GB
(180,60,30) 20 hours
PareTO
Nvidia GTX
480, 1.5 GB
4 mins
UW-Madison
PareTOWorks (SolidWorks Integrated)
suresh@engr.wisc.edu
Real-time Design
Topology Optimization
Topology Optimization
Minimize weight within design-space subject to stress constraints
under 4 different load-conditions!
450 Entries!
PareTO: Maximize Stiffness
Optimal design for
Maximizing Stiffness
(30% vol fraction)
Time taken: 8 mins
Laptop CPU: I7 with 480M GPU
PareTO: Maximize Strength
Optimal design for
Maximizing Strength
(30% vol fraction)
Time taken: 14 mins
Laptop CPU: I7 with 480M GPU
Optimal topology
Going beyond 3D Printing
Bridge Problem
Bridge Problem
V = 30% 1 min 10 secs
Airframe Seat
Wheel Support
Designing Braces for Buildings
Acknowledgements
Graduate Students
NSF
UW-Madison
Kulicke and Soffa
Luvata
Design Concepts
Publications available at
www.ersl.wisc.edu
suresh@engr.wisc.edu

3DPrinting_Suresh