An ambitious designer used Rhino to design and fabricate 20 variations on a chair in four months.For a designer aiming to streamline the gap between design and manufacturing, parametric modeling tools are a natural solution. LA-based Alexander Purcell Rodrigues found a place to work in just such a way at the Neal Feay Company (NF), a 60-year old fabrication studio in Santa Barbara, California, that is known for its exceptional metalworking. Together, the designer and the fabrication studio created the Cartesian Collection of chairs, aptly named for the analytic geometry that helped facilitate close to 20 design variations on the same aluminum frame in just under four months. “Not only were we pushing the boundaries of aluminum fabrication, the aim was to simultaneously create a lean manufacturing process,” said Rodrigues. Using Rhino with a Grasshopper plugin, Rodrigues developed a design for a chair that weaves together the simplicity of Western design with the complex ornamentation of traditional Eastern aesthetics. While the lines of the chair are clean and smooth, intricate embellishments on the back traverse multiple planes and angles, all on a shrunken scale. The time savings involved in designing with Rhino allowed the creation of another 19 variations on the theme. Rather than working with large billets of aluminum, Rodrigues and NF’s Alex Rasmussen opted to fabricate the chair from ½-inch stock, with an option for wooden legs or an upholstered seat. “The most difficult thing was the back rest because it required the most unconventional process,” said Rasmussen. “Once it was bent into a the basic form, the back was put into a four-axis machine that works in an X, Y, Z, and rotational axis to apply texture.” An anodized finish, which transitions between two colors for an ombré effect, adds to the bespoke appearance. Working collaboratively to solve hiccups in the fabrication process was a key component to the success of the project, and experimenting with tool paths helped create new patterns. Manipulating the original design in Grasshopper accounted for even minute deflections in the real-world fabrication scenario. “With this formula, you can play with variables that go in a hundred directions and multiply quickly,” Rodrigues said of the freedom of working in the program. “The world is your oyster in Grasshopper.” The team worked with aluminum for the frame of the chairs, a material choice that was made in part due to the fact that NF specializes in the material. In addition, the lightweight metal allowed a greater degree of accuracy than injection or press molding. “You can get all the screw caps and holes so exact with a precision of perfection you can’t recreate in other materials,” said Rodrigues. “And experimenting with the ombré anodized finish, NF pushed the boundaries very well, for something so thin and elegant.”
Posts tagged with "Grasshopper":
The 22-foot Elevator B honeybee habitat was the winning proposal in a design competition sponsored by Rigidized Metals and the University at Buffalo.The disquieting phenomenon of colony collapse disorder is seeing global bee populations vanish before our eyes, threatening the pollination of much of the world’s food crops. So when Buffalo, New York, metal fabricator Rigidized Metals discovered a colony of bees in an abandoned grain silo that its owner purchased, the company sponsored the Hive City competition. Students at the University at Buffalo (UB) were invited to design a viable bee habitat that would spark interest in the Silo City area and demonstrate the strengths of various building materials suppliers in Buffalo’s First Ward. As the first, permanent new construction on the Silo City site, Rigidized Metals wanted something that would be visible from nearby Ohio Street, stand out in the industrial landscape, and be reverent to neighboring silos. The winning design, known as Elevator B, is a 22-foot tower of 18-gauge sheet metal panels, with strategic perforations for natural ventilation, light, and heat management. An operable bee "cab" in the interior supports the actual hive on a pulley system, allowing beekeepers to access the colony and return it to a level that keeps the population safe from predators. "We did lots of research on how bees build hives and colonies," said Courtney Creenan, a student at UB's School of Architecture and Planning, and one of the designers of Elevator B. "The structure also induces the motion of standing inside of and looking up through a grain silo, where you have no where to look but up." However, instead of a perfectly rounded oculus at the tower’s summit, Elevator B viewers see the outline of a honeycomb. The student design team mocked up the tower with plywood cutouts in UB's School of Architecture workshops and Rigidized Metals fabricated the panels, but the design was completed in Grasshopper. The software helped determine a workable pattern of perforations, particularly along the top of the elevator where winds could compromise stability. In the team’s initial design, all of the 70 metal panels received an 80 percent perforation, though each had a unique number of cuts in a unique array. Grasshopper brought out the commonalities from these disparate patterns, and allowed the team to scale back to six types of panels with maximum perforations of 60 percent. "You can barely see a difference," Creenan commented. Once the design was simplified in Grasshopper, the Elevator B team devised a matrix to deliver to Rigidized Metals that indicated the number of panels to be fabricated and which had to be folded around the corners of the tower's steel frame. To ensure accurate installation on-site, each panel was numbered. Since the grain silos are unoccupied most of the time, with the exception of special events and tours, the tower had to be vandal resistant. The students fastened the panels to the frame with self-tapping screws, which required no predrilling. The steel frame was hand-made and the panels were machine-formed, but Creenan said there was little error and the pieces came together easily onsite. Beekeeper Phillip Barr successfully relocated the bee colony in the spring of 2012 and it has survived its first Buffalo winter. With the warmer weather, the colony's member numbers are on the rise. And though Elevator B was designed specifically for bees, Creenan said that other animals have taken a shine to the tower. “Before [the bees] moved in we noticed robins had nested there," she said. Though the design team hasn't been approached about adapting its design for other animals throughout Buffalo's Olmsted-designed park system, Creenan likes the idea. "It'd be interesting to test this somewhere else in the city," she said.
Re:site and Metalab's site-specific installation for Texas A&M's 12th Man Memorial Student Center uses 4,000 networked LEDs to create an animated display that speaks to tradition as well as to the future.The Corps of Cadets. Kyle Field. The 12th Man. Reveille. Texas A&M has more than a few strong traditions, most of which are centered around and given expression by the university’s football games and its alumni’s illustrious history of military service. At the same time, the school is well known for its robust and forward thinking science and engineering departments. Both of these characteristics factored into the conception for a permanent sculpture to inhabit A&M’s new Memorial Student Center (MSC). Created by art collaborative RE:site and design and fabrication studio Metalab (both located in Houston) the sculpture, titled Memory Cloud, is a chandelier of 4,000 white LEDs that are animated by two distinct feeds: one derived from archival footage of the Fightin’ Texas Aggie Band, the other from live infrared cameras that monitor people passing through the center’s atrium. “To interpret tradition visually we thought of moving patterns of people,” said Norman Lee of RE:site. “A&M has a strong marching band. If you remove the specifics of what the band is wearing and focus on the movements, they’re the same from 1900 to now. Once you reduce the figures from archival footage to silhouette patterns, you can’t identify the different points in time. Time and space collapse and bring together the school’s tradition in visual terms.” The archival silhouettes interlace with silhouettes from the live feed, generating ambiguous patterns that take time to sink in. “We envisioned incoming freshmen seeing the shadows and after three or four weeks realizing what the figures are in a powerful ‘ah ha’ moment,” said Lee. Memory Cloud is composed of a 14-foot-wide by 21-foot-long diagrid 1/8-inch powder-coated carbon steel frame and 220 LED arrays housed in clear acrylic tubes that hang in 21 rows from 16 gauge aluminum raceways carrying the data cables and electronics. The arrays are between 9 and 13 feet long and end in acrylic disks that are angled to give a billowing profile to the bottom of the sculpture. The disks also act as luminaires, picking up and diffusing the light of the lowest LED node via fiber optic effect. The piece is suspended from one point on the ceiling with a cable rigging. A winch can raise or lower it for maintenance. RE:site and Metalab used Rhino and Grasshopper to model Memory Cloud’s geometry as well as to develop quantitative data sets for the lighting purchase orders and assembly inventories. The diagrid structure was developed by Houston-based structural engineering firm Insight Structures using finite element analysis (FEA) software that determined a varying depth of profile to deliver the necessary support within the weight requirement. “We had a weight limit of 3,000 pounds,” said Andrew Vrana of Metalab. “At first we wanted to use 3/16 aluminum, which is light weight, but it deformed too much under welding. So we went with carbon steel and by optimizing the profile wound up with a final weight of 2,400 pounds.” The team also used the Lunchbox plugin for Grasshopper, which was developed by Nathan Miller of CASE, which helped to create clean data structures that retained their organization as the geometry of the cloud was refined. To create and program the LED matrix, RE:site and Metalab worked with Digital Media Designs (DMD), which did the digital lighting display for the 2008 Summer Olympics in Beijing. The company worked with a Chinese manufacturer to develop a custom LED product capable of meeting the sculpture’s size requirements while functioning within a broad range of daylight conditions. It also had to create a DMX control system that would take RE:site’s 2D silhouettes and replicate them in Memory Cloud’s 3D LED matrix, an unprecedented task from a software point of view. DMD worked with UK company Avolites Media to customize their AI software to this purpose. “With that software we were able to utilize a method called pixel mapping and find a way to interpret RGB values into black and white and also to transpose that into XYZ coordinates, creating a 3D virtual cloud,” said Scott Chmielewski of DMD. Memory Cloud was prototyped and fabricated in Houston, then trucked the 100 miles to College Station. The on-site assembly and erection process took 10 days to complete. Gig ‘em Aggies!
Kenneth Tracy and Christine Yogiaman of yo_cy applied research from working with concrete to dispel the singular material tendency of digital fabrication.Out of 68 submissions from 17 countries across four continents, the winning proposal of Tex-Fab's APPLIED: Research through Fabrication competition at the University of Texas at Arlington came from Kenneth Tracy and Christine Yogiaman of yo_cy, a collaborative design studio that utilizes digital techniques for maximum design effect. Their winning idea is called Cast Thicket, a study in tensile concrete that takes off in variations like a game of Cat's Cradle. "The initial idea was to apply our research toward the competition," said Tracy. The designers used their experience with an Indonesian material called bilik—a soft, woven bamboo mat typically used as a vertical divider—that helped form a fabric, cast concrete wall for a residential project in Southeast Asia. "We wanted to make something from a construction material that is normally very heavy looking [and] invert the stereotype of the carved aesthetics of concrete to create something that is lacy, thin, and delicate." While most concrete molds utilize steel or plywood casing, Tracy and Yogiaman opted for a .03-inch thick plastic that deforms once filled to create a unique textural detail not unlike the bamboo Indonesian mats. To design the columns and create variations in their diameter, yo_cy used Kangaroo. This plugin for Grasshopper simulates the surface shrinking and swelling typical of concrete, giving the designers a good idea of how their project would look when completed. The duo hopes the successful use of a thin, recyclable plastic mold could reduce the environmental impact of site-cast construction in the future. Cast Thicket is composed of 44 struts that intersect at several nodes. The struts are reinforced with a cage flat steel and thin steel tubes spanning between a wooden pallet base and capping sheet. Within the nodes are moments of tension, where the lacy network of lines are gathered together. "You can see this in Kangaroo like a set of strings, like a Cat's Cradle game," explained Tracy. "The idea is that a system can deal with contingencies of a complex architectural form. Rather than make a space with the piece, we wanted to create a set of conditions, like a network that proved its own variability and flexibility." The designers wanted a lightly colored material, something stronger than traditional cement that would pick up light and shadow, thus highlighting surface details. They chose an aggregate of materials void of dark tones, including limestone powder, white fiber reinforcement, Poraver glass beads for weight reduction, and metakaolin—a common material in porcelain. A superplasticizer that reduces viscosity binds the mixture. "It helps to see the way materials behave in construction, but physical testing is critical," said Tracy of Cast Thicket's ability to bear weight. "[With this project] we are reacting to the singular material tendency of digital fabrication and [we have shown that] we can use the computer to coordinate different methods of making a material, and simulate that on a smaller scale."
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A south-facing heat sink mass wall stores heat and diffuses light, creating an all-seasons solarium for an energy efficient home in Upstate New York.Dana Cupkova and Kevin Pratt, founders of Ithaca-based design and research practice Epiphyte Lab, met the client for which they built Hsu House in one of Cupkova’s classes at Cornell where she teaches design and fabrication strategies for ecologically adaptive construction systems. The client, a medical doctor, was in the class with the goal of designing his own energy efficient home in Danby, New York, but after an initial consultation, asked Cupkova and Pratt to design it instead. The 2,200-square-foot house is designed using passive solar principles. Interiors are organized around a three-story living space, which also functions as a ventilation stack. At its center, a south-facing, cast-in-place concrete mass wall creates a heat sink for the house, absorbing heat in warm weather and releasing it when the temperature drops. “It tempers the internal environment of the house,” said Cupkova. “It’s a giant radiator and cooling device. The house has no AC.” Designing the wall posed several challenges. The team had to create a shape with a large surface area to maximize thermal transfer from the sun to the wall to the home’s interior. But the wall also had to let daylight into the space and, as the sculptural focus of the house, have an interesting shape and texture. The team began by testing hundreds of parametric iterations of the wall using Grasshopper software, optimizing the design for four-foot-wide concrete formwork components to keep costs down. When Cornell’s CNC mill became unavailable, they turned to Syracuse fabrication company SCCM. Because CNC-milling the high-density polystyrene concrete form liners resulted in a bumpy texture, the team had to rethink its fabrication strategy. “Andy McDonald at SCCM was seminal in helping us figure out the project,” said Cupkova. Frank Parish, Cornell’s digital fabrication shop technician, helped oversee the work. Instead of working with the concrete form liners directly, the shop CNC milled more than 100 guides for the forms, which were then laminated and hand-cut using a hot wire-cutting knife. Once the forms were in place at the house, the entire structure was reinforced with rebar, allowing it to support part of the floor above. The wall is 23 feet long and 14 feet high with widths varying from 5 1/2 to 16 inches. As Its conical shapes created funnels in the formwork, the concrete mixture had to be adjusted to be more fluid. According to Cupkova, the job is an atypical one for the Ithaca area’s concrete trades, and she credits general contractor Paul Hansen Construction with making the project run smoothly (the fact that she was eight months pregnant also helped her gain some sympathy). As concrete was poured the wall was vibrated, allowing the material to fill the small spaces in the forms. The entire pour was completed in three hours. Now, the house has weathered two seasons without much use of heating or even electric lights thanks to the mass wall. “In the summer, after it was finished, the temperatures were in the 90s and it was 70 indoors,” said Cupkova. “It works.”