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Manufacturing

Next Wave of Product Development?

4 Jun, 2008 By: Jeffrey Rowe

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RAPID 2008 showcases the future of rapid manufacturing and reverse engineering technologies.

I just returned from the RAPID 2008 Conference & Exposition. Presented by the Society of Manufacturing Engineers (SME), it's the largest event of its type for rapid prototyping (RP), rapid manufacturing (RM), and reverse engineering (RE). It's also one of the technical events I look forward to each year, because so much in this arena is changing so quickly. For me, it was a good chance to get away from 30-degree temperatures in Colorado to 90-degree temperatures in Orlando, Florida.

Conference sessions are divided into rapid prototyping/manufacturing (translating digital CAD data into a physical object) and reverse engineering (converting a physical object into digital data for use with CAD). Here's a look at what I saw and heard.

Digital to Physical
One of the most significant trends I noted this year was the definite shift in the area of additive fabrication technologies (manufacturing processes that build up material layer by layer, as opposed to traditional machining, which is subtractive). We're moving from short-run rapid prototyping to longer run rapid manufacturing.

This trend was affirmed by our friend Terry Wohlers in his conference keynote speech, "The Future of the Industry." Wohlers, author of the Wohlers Report 2008, said RP has exhibited impressive growth of 116% from 2004-2007 in terms of the installed base and unit sales. However, he considers that RM has tremendous untapped growth potential, especially in using RM to produce end-use parts. As a matter of fact, Wohlers expects RM to become the largest future application of additive fabrication technologies.

Because of the automated nature of additive fabrication machines, Wohlers believes that using these hands-off manufacturing techniques could result in labor reductions. He said the manufacturing of tomorrow could go the same route as agriculture, with just a small minority of the population ultimately involved and actively engaging in the activity. Finally, drawing an analogy to the Erector Set Thingmaker, Wohlers postulated the eventual emergence of a $99 3D printer and the possibility of distributed manufacturing in neighborhood 3D print shops.

On the RAPID 2008 exhibit floor, the most interesting product I saw for RP/RM was the Stratasys FDM 900mc, a direct digital manufacturing (DDM, another name for RM) machine that produces 32 of its own parts, including the machine's controller touch-screen bezel. Stratasys estimates that using DDM to create the production parts saved at least $100,000 and six weeks compared with traditional tooling costs and time. The FDM 900mc is a big machine with a big build envelope -- 3' x 2' x 3' -- and is able to process some sturdy materials, including ABS and polycarbonate.

Physical to Digital
Reverse engineering is fundamentally a process of examining a physical object by first scanning it, but not modifying the data. However, the scanned data can be modified using downstream applications such as CAD.

There are basically two parts to the data-related portion of reverse engineering: scanning and data manipulation. Scanning (or digitizing) gathers geometric point data from a physical object. Several contact and noncontact technologies can be used to collect 3D data, and each technology has advantages and disadvantages. The collected data describes the physical object in 3D space, creating a point cloud, which defines points on the surface of a scanned object as x, y, and z coordinates. At each x, y, and z coordinate in the data where there is a point, there is an associated surface coordinate of the original object. The point cloud data usually must be cleaned up using an intermediate processing software package before exporting to a CAD application.

In the minds of many users, processing point clouds takes too long because it is computationally intensive, although 64-bit computers and software may help here. Also, it can take practice to discern from a point cloud what is "noise" and what will be useful data for a model. However, developers of point cloud processing software are striving to automate the process and eliminate steps. The ultimate dream would be to get scanned RE data directly into a CAD package, but that goal is still some distance away from realization.

Is RE widely used? During a keynote session, the audience was asked how many were currently using RE hardware, software, and techniques, and a few hands were raised. When asked how many were interested and considering it, approximately 10 times as many hands went up -- a good indicator for the future of reverse engineering.

One of the major complaints about reverse engineering hardware over the years is still heard today -- namely, that reverse engineering software is too fragile and better suited to a laboratory than a factory floor. Hostile factory environments have been known to destroy RE hardware in a matter of hours, but this situation appears to be improving, especially with noncontact laser and white light scanning devices.

During his keynote address, "Reverse Engineering: Progress and Promise," Todd Grimm, president of T.A. Grimm & Associates, said that in some circles, 3D scanning may ultimately replace coordinate measuring machines (CMM) for dimensional measurements during inspection processes. He also said that, similar to how FEA (finite-element analysis) has become more prominent in the design process, inspection considerations might find their way into the design process, as well.

The reverse engineering tool that caught my eye was the Creaform EXAscan laser scanner. It's a self-positioning, handheld 3D laser scanner with three high-definition cameras that provide high scanning resolution (0.002" in x, y, and z axis) and data acquisition accuracy (0.0016"). It is relatively lightweight (less than 3 lb), so it doesn't need an articulating CMM arm or other external tracking device to support it. To determine its position is space, the EXAscan uses the cameras to locate reflective targets previously placed on or around the object to be scanned and following a random mesh pattern. The data captured by the cameras is then used to create a mesh model. A unique feature of the EXAscan is a multiresolution function that automatically sets the optimum resolution level of the data acquired according to the complexity of the surface it is scanning.

Reverse engineering is an emerging technology that continues to attract new users and applications, and not just engineers and engineering. Cadalyst magazine (May 2008) devoted a special section to RE technologies. RAPID 2009 will take place May 12-14, 2009, at the Renaissance Schaumburg Convention Center in Schaumburg, Illinois.

Reverse engineering and additive fabrication are changing product development and manufacturing processes. Together, could they be the impetus behind the next industrial revolution? It's hard to say for sure, but it's possible.