CS 184, 5/11/2009CS 184, 5/11/2009

My Own Use of

Computer Graphics

Carlo H. Séquin

University of California, Berkeley

Brent CollinsBrent Collins

“Hyperbolic Hexagon II”

Brent Collins: Stacked SaddlesBrent Collins: Stacked Saddles

““Hyperbolic Hexagon” by B. CollinsHyperbolic Hexagon” by B. Collins

6 saddles in a ring

6 holes passing through symmetry plane at ±45º

= “wound up” 6-story Scherk tower

Discussion: What if … we added more stories ?

or introduced a twist before closing the ring ?

Scherk’s 2nd Minimal SurfaceScherk’s 2nd Minimal Surface

Normal“biped”saddles

Generalization to higher-order saddles(monkey saddle)“Scherk Tower”

Closing the LoopClosing the Loop

straight

or

twisted

“Scherk Tower” “Scherk-Collins Toroids”

Sculpture Generator 1Sculpture Generator 1, GUI , GUI

Slices through Slices through Minimal TrefoilMinimal Trefoil

50% 10%23%30%

45% 5%20%27%

35% 2%15%25%

One thick slicethru sculpture,from which Brent can cut boards and assemble a rough shape.

Traces represent: top and bottom,as well as cuts at 1/4, 1/2, 3/4of one board.

Profiled Slice through Profiled Slice through HeptoroidHeptoroid

Emergence of the Emergence of the Heptoroid Heptoroid (1)(1)

Assembly of the precut boards

Emergence of the Emergence of the HeptoroidHeptoroid (2) (2)

Forming a continuous smooth edge

Emergence of the Emergence of the HeptoroidHeptoroid (3) (3)

Smoothing the whole surface

The Finished The Finished HeptoroidHeptoroid

at Fermi Lab Art Gallery (1998).

Various “Scherk-Collins” SculpturesVarious “Scherk-Collins” Sculptures

Rapid Prototyping with FDMRapid Prototyping with FDM

A Look Into the FDM MachineA Look Into the FDM Machine

Galapagos 6 sculpture in progress

2 NOZZLES

Extending the Paradigm: Extending the Paradigm: Totem 3Totem 3

Bronze Investment Cast

The Team: “Whirled White Web” (C. Séquin, S. Wagon, D. Schwalbe, B. Collins, S. Reinmuth)

Snowsculpting Championships 2003Snowsculpting Championships 2003

Removing lots of snow …

Day 1Day 1

Day 2: Making a TorusDay 2: Making a Torus

Day 3, pm: Carving Flanges, Holes Day 3, pm: Carving Flanges, Holes

Day 4: Geometry RefinementDay 4: Geometry Refinement

“Devil’s Toothbrush”

Day 5, am: Surface RefinementDay 5, am: Surface Refinement

12:40 pm -- 4212:40 pm -- 42° F° F

12:41 pm -- 4212:41 pm -- 42° F° F

““WWW” Wins Silver MedalWWW” Wins Silver Medal

Brent Collins’ Brent Collins’ Pax MundiPax Mundi

1997: wood, 30”diam.1997: wood, 30”diam.

2006: Commission from H&R Block, Kansas Cityto make a 70”diameter version in bronze.

My task: to define the master geometry.

CAD tools played important role.

Emulation; Define Master PatternEmulation; Define Master Pattern

Use 4 copies.

Master to make a mold from.

Alignment tab

Design of Two-Part MasterDesign of Two-Part Master

Alignment tabs for easy assembly

Subdivide into Subdivide into TwoTwo Master Segments Master Segments

Joe Valasek’s CNC Milling MachineJoe Valasek’s CNC Milling Machine

Styrofoam milling machine

Machined Master Pattern #2Machined Master Pattern #2

(Cut) Master (Cut) Master Silicone Rubber MoldSilicone Rubber Mold

MoldMold Several (4) Wax Copies Several (4) Wax Copies

SpruingSpruing the the Wax PartsWax Parts for Casting for Casting

Ceramic Slurry ShellCeramic Slurry Shell Around Wax Part Around Wax Part

ShellShell Ready Ready for Castingfor Casting

Casting with Casting with Liquid BronzeLiquid Bronze

The Freed The Freed Bronze CastBronze Cast

Assembling the SegmentsAssembling the Segments

The “Growing” RibbonThe “Growing” Ribbon

Applying PatinaApplying Patina

Front Door of the ...Front Door of the ...

H&R Block Building

The Final DestinationThe Final Destination

Steve Reinmuth Tightening the BoltsSteve Reinmuth Tightening the Bolts

Brent Collins Polishing Our BabyBrent Collins Polishing Our Baby

Thanks to Steve Reinmuth ...Thanks to Steve Reinmuth ...

for creating the beautiful patinas,

for the fabrication photographs.

Questions ?Questions ?