Laser Scanning Enables Design Of Waffler That Produces Waffles With Floral Pattern

When engineers at Tilia made the decision to design a VillaWare branded waffler that produces waffles that are not only delicious but also beautiful they faced a major challenge. They hired a studio to sculpt a design for the surface of the waffler that incorporates a bouquet of roses while also meeting the geometric requirements needed to pull the waffle out of the iron. The design exceeded the company's expectations but was so geometrically complex that engineers felt it would be very difficult to manually create the solid model geometry required for accurate and efficient manufacturing. "We had reproduced physical models several other times using laser scanning and felt this would be the right tool for the job," said Jesse Patterson, Mechanical Design Engineer for Tilia. "We sent the model to the GKS Inspection Services division of Laser Design Inc. (Minneapolis, Minnesota) and only four days after they received it they provided a 3D solid model that was geometrically accurate and visually indistinguishable from the original. On this and other projects, we have found laser scanning to provide a fast, accurate and affordable method of reproducing geometrically complex physical models."

Tilia, Inc. produces FoodSaver home vacuum packaging systems and VillaWare small electric kitchen appliances, cookware, and kitchen tools. VillaWare products are distributed through leading specialty chain and independent cookware stores throughout the U.S. and Canada. The Villaware electric line includes UNO Wafflers, UNO Panini Grills, Dual Station Smoothee-Bars, Ice Cream and Gelato Makers, Power Cookie Presses, Classic Coffee Urns and other products. The new VillaClassic™ and Victorio™ cookware lines are hand-poured and gravity-cast to provide slow, even and flavorful cooking. VillaWare offers a traditional collection of kitchen tools, including Imperia and Al Dente pasta machines, Bravo™ pizza stones, food strainers, meat grinders, espresso pots and many hard-to-find specialty hand tools.

Unique waffler design

The new VillaWare waffler goes far beyond previous products in that it produces a waffle with a complex 3D shape, in this case a bouquet of roses. "We already have the reputation for designing award-winning waffle makers but now we are enabling our customers to use our products to produce waffles that are not only delicious but beautiful as well," Patterson said. "I don't know of any waffle iron that has ever offered a waffle with an organic 3D design before. Our goal with our latest design was to get our customers to say ‘wow'! We roughed out the floral design that we wanted to produce and hired a design studio to sculpt a model. The studio's job was not easy because they had to produce a design that was beautiful while also meeting our physical requirements, which for a waffler are similar to injection molding. In particular, the contours of the pattern need to have a draft angle to make it easy to remove the waffle. The design studio, of course, was more accustomed to meeting aesthetic than engineering concerns, so several iterations were required. At the end of this process, we had a design that was beautiful and also met the physical requirements needed to make a perfect waffle."

With the model completed, Tilia engineers next faced the challenge of converting it to the solid model they needed to produce the mold used to die cast the waffler. "It would have been very difficult for a CAD designer to duplicate the studio's creation by hand," Patterson said. "If we had asked one of our designers to take on this arduous task, the chances are they would have spent weeks or even months without ever capturing the beauty of the floral design. Today's CAD software offers some 3D contouring capability but not anywhere near the level that would be required to accurately capture a design of this complexity. A designer would have to capture tens of thousands of points with a CMM to come anywhere close to depicting the beauty of the original design." The use of CMMs to inspect parts is time-consuming because of the need to manually move the machine probe into position for each individual point to be measured. As the geometrical complexity of the part increases, the number of points needed to fully characterize the geometry skyrockets. Even if operators spend several weeks generating thousands of points, they can never be sure that they haven't missed a critical feature.

Patterson was aware of the technology of laser scanning and thought it would be the best way to convert the sculpture's model to a CAD file. Laser scanning systems work by projecting laser light onto surfaces while cameras continuously triangulate the changing distance and profile of the laser as it sweeps along, enabling the object to be accurately replicated. Laser scanners are able to quickly measure large parts while generating far greater numbers of data points than touch probes without the need for templates or fixtures. Laser scanning can replicate the complete geometry of a complex part to a high level of accuracy, often to within 1 thousandth of an inch. The model can also be superimposed upon the original design geometry to determine exactly where they differ. Since there is no probe on a laser scanner that must physically touch the object, the problems of depressing soft objects and measuring small cavities are eliminated. But with a relatively small number of parts that needed scanning every year, it made no sense for Tilia to buy a laser scanner. The cost would have been high and the company would have faced the challenge of training operators and maintenance staff. They also would have faced the risk that the machine could become obsolete before it had paid for itself.

Capturing the organic beauty of the model

Patterson said that soon before this need arose, Tilia had begun working with GKS Inspection Services, a service bureau that offers laser scanning services on a project basis. "We originally found them on the Internet," he said. "We were in a crunch and needed to quickly convert a physical object into a 3D CAD Design. They kept their word by meeting our schedule and the quality of their work was outstanding. When the waffler project came along it was natural to use them again. I shipped the model to them so it arrived on a Monday. They scanned the parts and generated a point cloud in which each individual point was accurate within 20 microns and the surfaces generated from the point cloud were accurate to at least 0.004 inch. By Thursday they emailed me a 3D solid model of the waffle iron. We checked some of the surfaces and they were right on. Just as important, they had captured the organic beauty of the design, which would have been almost impossible by hand. The ability to translate this complex model into a CAD in just a few days for a very reasonable price played a key role in getting the product to market on schedule."

"CAD software is great for defining structured geometry but it's no match for the complex curves involved in reproducing a living object," Patterson concluded. "Laser scanning provided the ideal solution to our problem by maintaining high accuracy while picking up all of the small details required to deliver an aesthetically pleasing and manufacturable product. The waffles produced by our new waffler look like you froze several flowers into them, exactly the look that we were trying to achieve. We used the solid models provided by GKS Inspection Services as the starting point for designing the die casting molds used to produce the wafflers. We have produced six different variations on the design, some that we will sell under our own name and others for our private label customers. GKS's willingness to work with us and meet our needs promptly played a key role in our ability to bring an innovative and creative design to market in the shortest possible time. The waffler market has been fairly staid and laid back up to now but we intended to really shake it up. Our plan is to make this new product just the first in a series of designs that produce waffles that look almost too good to eat."

SOURCE: Structured Information