A Minnesota company designs and manufactures a unique line of small electrically powered watercraft inspired by the enjoyment of personal recreational experiences up-close in the land of 10,000 lakes.
In the land of 10,000 lakes, small, electrically powered watercraft are popular. For one Minnesota company to scale up production, though, it needed a better way to design and prototype. Employees had been designing and prototyping by hand, which meant that any prototypes were not totally uniform and symmetrical.
In addition, the company’s suppliers began requesting CAD data of the deck and hull so they could precisely make and fit ancillary parts for it. Thus, management determined that 3D electronic representation of the fiberglass craft would vastly improve the dialog with suppliers and vendors.
Plus the ability to reverse engineer the boat from digital data was deemed essential for the higher level manufacturing processes the company would use. Because the body of the boat was a complex shape with many free-form curves and surfaces, hand measurement would have been difficult even with detailed 2D drawings, much less precise and thorough, and much more time consuming.
The recurring issue of not having a CAD model compelled the company to contract an engineer who had CAD skills. The engineer immediately recommended that they have the boat 3D laser scanned at GKS Global Services, a leading provider of ultra-precise 3D scanning services.
To facilitate tweaks and updates to the hand-made design, the engineers decided they needed a parametric model that could be revised and edited (rather than a non-parametric or “dumb” model that could not). The GKS representative explained the pros and cons of each approach, dumb vs. parametric modeling, including the cost/benefit trade-offs of each.
A major challenge in converting a hand-made as-built fiberglass prototype into a manufacturable product is bringing the geometry back to its design intent. The editable parametric CAD model would allow the engineers to create uniform wall thicknesses and perform tests on the design to ensure its quality and function. It would provide the data needed to make exact copies of parts and to aid the development of tools that enable a higher level of manufacturing in greater quantities.
The company decided that only the outward-facing side of the deck and hull needed to be captured, so the parts were bolted together and scanned as an assembly. With the external profile data, uniform wall thicknesses could be constructed in the modeling process.
GKS engineers scanned the fiberglass craft using the Laser Design FA system with the 10 ft Platinum FaroArm® and the SLP-2000 line laser probe. The SLP-2000 offers a super-long 240 mm (9.8 in.) laser line for faster scanning with better coverage than most handheld scanning systems on the market today (0.0029 in. accuracy). The set-up and scanning took just 3-4 hours.
The laser scanning system projects a line of laser light onto all of the part’s surfaces while cameras continuously triangulate the changing distance and profile of the laser line as it sweeps along. Non-contact scanning greatly reduces the problem of missing data on a complex free-form surface.
The system measures fine details so that the object can be exactly replicated digitally. Laser scanners measure articles quickly, picking up to 75,000 coordinate points per second, and generate huge numbers of data points without the need for special templates or fixtures.
The laser scan reproduced the part profile completely and precisely in the coordinate point cloud. The native software (Surveyor Scan Control) automatically connected the data from multiple views into a common coordinate system in a single 3D scan file. After the scanning was complete, the raw data was processed and refined. The processed data was then modeled into a symmetrical parametric CAD model in SolidWorks. Delivery was promised in 8-10 days, but actual turnaround time from quote to model delivery was just 4 business days.
Using touch measurement technologies to capture the boat’s curved irregular shapes would have taken much longer and produced a much less complete data set. Measurements taken by hand would have been sparser, never really capturing the totality of the shape. Without non-contact laser scanning, this type of exact true-to-life shape replication of hand-made prototypes would be virtually impossible.
The parametric CAD model in SolidWorks was delivered within the week. The differences between the raw scan data and the CAD model were evident; the imperfections in the prototype were corrected back to their design intent in the smooth model.
The next step in the development process will be to analyze the design in CAD and make digital “prototypes” to try out various improvements without having to actually make different physical versions of the product. This will help immensely with designing add-ons and assemblies, and facilitate discussions with up-line parts’ suppliers. And every change is documented in the software and can be referred back to at any time.
GKS Services / Laser Design
www.laserdesign.com/services
Source: :: Make Parts Fast ::
