Calming NURBS with the Flare Storm (Tech Trends Feature)1 Mar, 2007 By: Kenneth Wong
form.Z Joint Study Program helps one student create an innovative flashlight radio.
Some time during the Fall of 2005, Luke Johnson, a student at the University of Bridgeport (Bridgeport, Connecticut), dispatched a somewhat perplexing questionnaire to a handful of friends and relatives. The young man wanted to know if they were pleased with their emergency flashlight radios: which features they liked best, which they liked least and why. He'd also been ambushing random people on the streets with similar questions. At times, he could be seen wandering along the aisles of electronic stores, scrutinizing the differences among various brands of flashlight radios. But Johnson wasn't thinking of buying one; he was actually designing one quite unlike those that were already on the market (figure 1).
Figure 1. The Flare Storm flashlight radio.
Make a Radio
At the time, Johnson was taking the Senior Industrial Design Studio class (www.bridgeport.edu/art/industrial). His instructor was John Houlihan. The assignment for the semester was to make an emergency flashlight radio that was powered both by battery and by hand. Students were required to develop the concept in sketches then finalize it in a computer program of their choice. Johnson dubbed his device the Flare Storm.
Johnson also happened to be in the Intermediate form.Z class, so that software became his primary modeling tool. Robert Brainard teaches the form.Z class and said that the project eventually ceased to be homework for Johnson. "He started having fun with it," Brainard recalled. "It got to the point where he was working on it nonstop."
Brainard also is a fan of SolidWorks. "I see form.Z as a playground, a 3D sketchpad," he explained. "When I just want to throw some ideas around, that's the tool I go to. When I've narrowed the ideas down to one design direction, and I'm in the refinement stage, I tend to switch to SolidWorks."
Brainard, who teaches a studio course in addition to form.Z and SolidWorks courses, advocates a tight integration between design courses and CAD courses. "In my CAD class, I go beyond teaching the CAD software and point out the design problems," he said. "In the design studio, the instructor would be pointing out CAD issues along with the design issues." For the flashlight radio project, Brainard and Johnson tackled the first critical design consideration: Who would use the Flare Storm?
"Most emergency radios are marketed to an older audience," Johnson pronounced as part of his discovery from his somewhat casual market study.
For the Flare Storm, Johnson said he chose "a younger audience, probably between the ages of 10 and 20." Keeping in mind his end users—teenagers stuck in a shelter with little or no distraction besides the emergency equipment around them—he decided to introduce playfulness to both the equipment itself as well as the manual powering method.
"I researched devices powered by squeezing, pumping and peddling," he said. "Eventually, I ended up with wheels as the charging mechanism." Setting aside devices inspired by pogo sticks and pushup exercise clutches, he settled on a design that resembled a Volkswagen Beetle (figure 2). "Since it would use the wheels to charge, I wanted to clearly communicate that to the user," he said. "So I adopted the vehicle shape."
Figure 2. Luke Johnson explored ideas for manually charging the emergency flashlight radio through pumping, pushing, squeezing and rotation.
Wheeling the device along a flat surface—something that can be done for amusement—would also generate power. "Think of children in an emergency situation—no power, no TV, no video game," Johnson's instructor Brainard said.
Having adopted the shape of a car, however, Johnson then had to struggle with an auto designer's headache: the fenders.
"I took my hand-drawn sketches and brought them into Adobe Illustrator to trace over the profile," Johnson said. "I was pretty adept with Illustrator, so I could get nice, clean curves easily. Once I got the ideal profile, I then exported it to form.Z." He then continued to develop the 2D profile into the desired 3D shape in form.Z.
Johnson said that his greatest challenge came when he got to the fenders above the front wheels. "I spent a lot of time trying to connect them to the main body and to blend them into one unit," he admitted. "I ended up creating them as NURBS [non-uniform rational B-spline] objects, extruding them right through the body, adjusting their radiuses, then trimming them off with some Boolean operations (figure 3)."
Figure 3. Several hexagons, each representing a basic section of the form, are arranged on an elliptical path to create the body (top left). Lines connect the corners of each hexagon with the adjacent hexagons to create a cage-like structure. The model is smoothed out with form.Z s skinning operation, which converts it into a NURBS object. Extruded cylinders are set up at the front and back of the body in preparation for more detailed operations to come (top right). The NURBS body is tweaked to adjust curvature, smooth out the rough spots and achieve symmetry. Separate bodies are joined using Boolean differences and additions. The tires and wheels are extruded and shaped with form.Z s editing tools (bottom left). More Boolean operations and blending are needed to join the surfaces. Then points on the surfaces are smoothed out further (bottom right) before final rendering.
Johnson anticipated that users might want to rotate the wheels with their fingers, as an alternative to pushing the device on the floor. As a reult, he included several finger cups in the Flare Storm's front wheels.
"During the modeling process, I discovered that I had not taken into account the depth necessary to get the finger inside the cup," he said. The shallowness of the cups would result in a user's finger constantly slipping out. "I had to go back, widen the body to accommodate slightly wider tires, then use the extra room to create deeper finger cups."
Ultimately, Johnson's Flare Storm won the Award of Distinction in Industrial Design for the form.Z 2006 Joint Study Program, an initiative by form.Z's maker auto•des•sys to support and subsidize the learning of the new digital tools in 3D modeling.
Kenneth Wong is a former editor of Cadence magazine. As a freelance writer, he explores innovative usage of technology and its implications. E-mail him at Kennethwongsf at earthlink.net.
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