CHS UCB AAAS 2001, San Francisco Procedurally Defined Geometrical Sculptures Carlo H. Séquin University of California, Berkeley Brent Collins Gower, Missouri.

Download Report

Transcript CHS UCB AAAS 2001, San Francisco Procedurally Defined Geometrical Sculptures Carlo H. Séquin University of California, Berkeley Brent Collins Gower, Missouri.

CHS
UCB
AAAS 2001, San Francisco
Procedurally Defined
Geometrical Sculptures
Carlo H. Séquin
University of California, Berkeley
Brent Collins
Gower, Missouri
CHS
UCB
My Professional Focus
Computer-Aided Design
 Design
useful and beautiful objects
with the help of computers.
 Develop
(interactive) computer programs
to make these tasks easier.
CHS
UCB
Computer-Aided Design I :
Integrated Circuits: “RISC I” chip (1981)
CHS
UCB
Computer-Aided Design II :
Mathematical Models
“Granny Knot”
Lattice
Berkeley
UniGrafix
(1982)
CHS
UCB
Computer-Aided Design III : Buildings
Soda Hall, CS Dept. Berkeley (1992)
CHS
UCB
Computer-Aided Design IV :
Mechanical Parts
Octahedral Gear
Design (1985)
Realization (FDM) (2000)
CHS
UCB
Computer-Aided Design V :
Abstract Sculpture (virtual)
(Since 1995)
CHS
UCB
Computer-Aided Design V :
Abstract Sculpture (virtual)
Scherk-Collins Tower
CHS
UCB
Computer-Aided Design V :
Abstract Sculpture (virtual)
Doubly-looped Scherk-Collins saddle-chain
CHS
UCB
Computer-Aided Design V :
Abstract Sculpture (real)
“Bonds of Friendship”
(2001)
Fabricated by: Fused
Deposition Modeling
Currently in S.F.:
at Gallery 650,
Delancy/Brannan
CHS
UCB
Roots of My Passion for Sculpture
My love for geometry and abstract sculpture
emerged long long before I learned to play
with computers.
Thanks to: Alexander Calder, Naum Gabo,
Max Bill, M.C. Escher, Frank Smullin, ...
CHS
UCB
Leonardo -- Special Issue
On Knot-Spanning Surfaces: An
Illustrated Essay on Topological Art
With an Artist’s Statement by Brent Collins
George K. Francis
with Brent Collins
CHS
UCB
Brent Collins: Early Sculptures
All photos by Phillip Geller
CHS
UCB
My Fascination with...
Brent Collins’ Abstract Geometric Art

Beautiful symmetries

Graceful balance of the saddle surfaces

Superb craftsmanship

Intriguing run of the edges

What type of knot is formed ?

Mystery: one-sided or two-sided ?
==> Focus on “Chains of Saddles”
CHS
UCB
Brent Collins: Stacked Saddles
CHS
UCB
Scherk’s 2nd Minimal Surface
Normal
“biped”
saddles
Generalization to
higher-order saddles
(monkey saddle)
CHS
UCB
“Hyperbolic Hexagon” by B. Collins

6 saddles in a ring

6 holes passing through
symmetry plane at ±45º

“wound up” 6-story
Scherk tower

What would happen,

if we added more stories ?

or introduced a twist
before closing the ring ?
CHS
UCB
Closing the Loop
straight
or
twisted
CHS
UCB
Collins - Séquin Collaboration
 Discuss
ideas on the phone
 Exchange
 Vary
sketches
the topological parameters
 But
how do you know whether it is
beautiful ? Need visual feedback.
 Making
models from paper strips
is not good enough.
CHS
UCB
Brent Collins’ Prototyping Process
Armature for the
"Hyperbolic Heptagon"
Mockup for the
"Saddle Trefoil"
Time-consuming ! (1-3 weeks)
CHS
UCB
Collins’ Fabrication Process
Building the final sculpture (2-3 months):

Take measurements from mock-up model,
transfer parallel contours to 1” boards.

Roughly precut boards, leaving registration marks
and contiguous pillars for gluing boards together.

Stack and glue together precut boards,
remove auxiliary struts.

Fine-tune overall shape,
sand and polish the surface.
A big investment of effort !
CHS
UCB
Collins’ Fabrication Process
Lamination process to make
an overall shape that within
contains the final sculpture.
Example: “Vox Solis”
CHS
UCB
“Sculpture Generator I”
Prototyping & Visualization tool for
Scherk-Collins Saddle-Chains.

Slider control for this one shape-family,

Control of about 12 parameters.

Main goal: Speed for interactive editing.

Geometry part is about 5,000 lines of C;

10,000 lines for display & user interface.
==> VIDEO
CHS
UCB
=== VIDEO ===
6
min
CHS
UCB
Base Geometry: One Scherk Story
 Hyperbolic
Slices ==> Triangle Strips
 precomputed
-- then warped into toroid
CHS
UCB
Slices through the Sculpture

One thick slice
thru “Heptoroid”
from which Brent
can cut boards
and assemble a
rough shape.
Shown are top and
bottom as well as
cuts at 1/4, 1/2, 3/4
of one board.
CHS
UCB
Our First “Joint” Sculpture
Six monkey saddles
in a ring with no twist
(like Hyperbolic Hexagon)
azimuth = –30°, flange 1.5
(aesthetics)
size, thickness
(fabrication consideration)
CHS
UCB
“Hyperbolic Hexagon II” (wood)
CHS
UCB
Heptoroid
( from Sculpture Generator I )
Cross-eye stereo pair
CHS
UCB
Emergence of the “Heptoroid” (1)
Assembly of the precut boards
CHS
UCB
Emergence of the “Heptoroid” (2)
Forming a continuous smooth edge
CHS
UCB
Emergence of the “Heptoroid” (3)
Smoothing the whole surface
CHS
UCB
Advantages of CAD of Sculptures
 Exploration
 Instant
visualization of results
 Eliminate
 Create
 More
need for prototyping
virtual reality pictures
 Making
 Better
of a larger domain
more complex structures
optimization of chosen form
precise implementation
 Rapid
prototyping of maquettes
CHS
UCB
Sculpture Design












branches = 4
storeys = 11
height = 1.55
flange = 1.00
thickness = 0.06
rim_bulge = 1.00
warp = 330.00
twist = 247.50
azimuth = 56.25
mesh_tiles = 0
textr_tiles = 1
detail = 8







bounding box:
xmax= 6.01,
ymax= 1.14,
zmax= 5.55,
xmin= -7.93,
ymin= -1.14,
zmin= -8.41
CHS
UCB
Breckenridge Competition
CHS
UCB
FDM Maquette of Solar Arch
 2nd
place
CHS
UCB
We Can Try Again … in L.A.
CHS
UCB
… or in Washington D.C.
CHS
UCB
V-art
Glass
Scherk
Tower
with
Monkey
Saddles
Jane Yen
CHS
UCB
SFF Maquettes of Future Sculptures
MonkeySaddle
Cinquefoil
CHS
UCB
Various “Scherk-Collins” Sculptures
CHS
UCB
Fused Deposition Modeling (FDM)
CHS
UCB
Looking into the FDM Machine
CHS
UCB
Zooming into the FDM Machine
CHS
UCB
Séquin’s “Minimal Saddle Trefoil”
 Stereo-
lithography
master
CHS
UCB
Séquin’s “Minimal Saddle Trefoil”
 bronze
cast,
gold
plated
CHS
UCB
Minimal Trefoils -- cast and
finished by Steve Reinmuth
CHS
UCB
Brent Collins’ Trefoil
CHS
UCB
Family of Symmetrical Trefoils
W=2
W=1
B=1
B=2
B=3
B=4
CHS
UCB
Higher-order Trefoils
W=1
(4th order saddles)
W=2
CHS
UCB
Exploring New Ideas
 Going
twice around the loop ...
Resulting in an interwoven structure.
CHS
UCB
9-story Intertwined Double Toroid
Bronze
investment
casting
from
wax original
made on
3D Systems’
“Thermojet”
CHS
UCB
Brent Collins: Pax Mundi
CHS
UCB
Keeping up with Brent ...

A bent “Scherk tower” is not able
to describe a shape like “Pax Mundi.”

Need a broader paradigm !

Use SLIDE modeling environment,
it provides a nice combination of
procedural modeling and interactivity.
CHS
UCB
SLIDE-UI for “Pax Mundi” Shapes
CHS
UCB
“Viae Globi” Family
L2
L3
L4
(Roads on a Sphere)
L5
CHS
UCB
Via Globi 3 (Stone)
Wilmin Martono
CHS
UCB
Via Globi 5 (Wood)
Wilmin Martono
CHS
UCB
Via Globi 5 (Gold)
Wilmin Martono
CHS
UCB
Conclusions (1)
 Interactive
computer graphics
is a novel (to artists) medium
that can play an important role
-- even for traditional artists.
 Virtual
Prototyping can save time and
can tackle sculptures of a complexity
that manual techniques could not conquer.
CHS
UCB
Conclusions (2)
 The
computer is not only a great
visualization and prototyping tool,
 It
also is a generator for new ideas and
 an
amplifier for an artist’s inspiration.
CHS
UCB
Questions ?
THE END
CHS
UCB
========= SPARE =========
=========================
CHS
UCB
Stepwise Expansion of Horizon
 Playing
with many different shapes and
 experimenting
at the limit of the domain
of the sculpture generator,
 stimulates
new ideas for alternative
shapes and generating paradigms.
Swiss Mountains
CHS
UCB
Figure-8 Knot with C-Section
CHS
UCB
Conclusions (3)
 What
makes a CAD tool productive
for this kind of work ?

Not just “virtual clay,”

partly procedural;

fewer parameters that need to be set.

Keep things aligned, joined;

guarantee symmetry, regularity,

watertight surfaces.

Interactivity is crucial !