How-Siang Yap, Agilent Genesys Product Manager, Agilent Technologies, Inc
Rapid board prototyping doesn’t always lead to faster product development, even though it may convey that comforting impression to the engineer or his boss. But, why is that the case?
The answer is fairly straightforward. It’s because the prototype depends on the design. If the design is flawed so too will be the prototype—no matter how rapidly it can be made.
A much more efficient and economical approach relies on rapid designing techniques in automatic circuit synthesis to evaluate multiple possible prototypes before building them. This approach is particularly relevant to RF boards where lumped and distributed components are required to achieve the optimum balance of cost and performance.
Traditionally, RF filters and impedance matching networks are prototyped and tweaked on the bench. Engineers who grew up using these cut-and-try techniques may view rapid prototyping as an improvement over their traditional process. However, the availability of affordable, accurate and easy-to-use synthesis and simulation tools for performing rapid virtual prototyping is now making rapid board prototyping much less relevant. Plus, rapid virtual prototyping is orders of magnitude faster. The accuracy of simulation can now consistently match that of actual measurements from prototypes, especially with the advent of 3-dimentional planar electromagnetic simulation.
Rapid virtual prototyping starts from automatic circuit synthesis, as shown in this video highlighting the evaluation of multiple RF impedance matching networks. In less than 10 minutes, the rapid virtual prototyping has already tested over a dozen possible prototype candidates for hardware implementation, weeding out those that don’t make the cut.
The lesson here is clear. Before jumping on the rapid prototyping bandwagon and wasting lots of energy tweaking prototypes to make them work, consider using rapid virtual prototyping on the computer first.
|Robert Charles, Director, Principal Engineer, Farm
As rapid prototyping has come down the cost curve and a wider variety of materials and processes have become available, it’s become a lot easier for designers and engineers to hit tight development schedules. The short lead time for the parts helps, but the real time savings is in being able to reduce project uncertainty more quickly than in the past. In the same time it would have taken several years ago to complete a complex structural or dynamic analysis, a real part can often be built and tested to demonstrate that it functions properly. Early in the development process, it’s easy to build multiple concepts and get a better comparison between them.
By reducing the technical uncertainty quickly, the development team can make decisions and proceed with detailed design more quickly. Upper management can make decisions sooner because they have more confidence in the concepts and can see and feel the models. The team can then make decisions based on facts rather than guesswork. The prototype parts are easy to justify, because they are relatively inexpensive yet provide truly valuable information.
Currently available RP technology has also helped to reduce lead times on parts based on more traditional processes like sheet metal fabrication and machining. Many businesses have streamlined their operations and can provide high quality parts quickly, partially in response to the different additive rapid prototyping technologies. Engineers are not limited only to plastic when they need parts in a hurry.
Eugene Lin, Product Marketing Manager, Agilent Technologies
3D printing has been a hot topic for a while now, and many people consider it as the next industrial revolution for mankind. The reason is because 3D printing helps with rapid prototyping in the mechanical world, enabling the creation of quick samples, exchange of ideas etc. There will be insufficient momentum to create an industrial revolution if there is no means of rapid prototyping in the electronics world.
Computerized circuit design and simulation are very powerful tools that took off a decade ago. System-on-chip and application ASICs have helped realize the dreams of many design engineers through the years. Normally, it is easy to verify and simulate circuit designs, but there aren’t too many improvements in real-time electronics manufacturing processes, especially in testing, to help get rid of manufacturing defects – before you can really start the verification of your design.
Just imagine, a average PCB these days has hundreds of components soldered on it. Just a single short can damage the whole board, and it can take hours to locate the short. Without testing, there is no confidence if the board will function well, free from the damaging effects of shorts, opens, or other workmanship defects introduced when soldering the components to the PCB.
Fortunately, technology has also advanced in the area of rapid prototyping for electronics manufacturing tests, in the form of innovations in boundary-scan and diagnostic test tools. By combining boundary scan with diagnostics tests, shorts and opens can be discovered with very simple fixturing which is built within hours - potentially by 3D printing! Test programs can be done in parallel (while you 3D-print the fixture). The combination of these two tools provide plenty of digital channels and measurement technologies to quickly test soldering of the IC, critical voltage points, perform pre-conditioning of the board, and execute boundary scan or other functional-test software. Instead of spending days to debug the prototype, now it can be done within one day.
Removing manufacturing defects is the key to unlock the bottleneck for rapid prototyping in electronics. If we think electronics has been evolving very fast in the last decade, it is just going to evolve even faster, spurring faster roll-out of new gadgets and gizmos for everyone to enjoy the new electronics world.
|Cliff Ortmeyer, Newark element14
The need for rapid prototyping has always existed, however with the development of new tools and technologies, many of the traditional hurdles of prototyping have been eliminated. For instance, LCD display design, GUI development, MEMS sensing, motor control, RTOS or OS usage, and cap touch sensing are just a few of the obstacles to rapid prototyping that we’ve been able to overcome. Thanks to the introduction of low-cost development kits and boards, the industry is able to speed up the entire process of prototyping, leading to more innovations and easier collaboration across different groups of engineers. For example, students today are using dev kits based on Raspberry Pi, BeagleBone or Arduino to apply that acquired prototyping knowledge to their jobs, relying on these platforms to show proofs of concept and bring their designs to life. These kinds of solutions often come with pre-loaded software and plug & play hardware accessories to make understanding code and system design simple.
Video training, project forums and communities like element14 have also flourished because of the push toward rapid prototyping and open source design. Increasingly complex dev kit accessories and processor-based designs have drawn more engineers to design communities for a broad array of support options.
Also, as the industry at large has made a strong move towards the ARM architecture, the ease of rapid prototyping has increased thanks to the reuse of tools, and conversion to other processors is easier than ever. Manufacturers are now increasingly providing more accessory boards that boast additional functionalities because of the need for rapid prototyping. Some examples include Texas Instruments’ LaunchPad and Booster Packs, Freescale’s Freedom boards and STMicroelectronics’ Discovery boards, to name a few. The design community has long been looking for ways to make rapid prototyping a possibility; with all of the new technologies and resources available to us today, it finally is.
Yuval Hernik, Senior Director of Application Engineering, VPG
While general-purpose low-precision resistors are widely available anywhere, as a supplier of precision components, VPG has committed itself to meeting our customers’ rapid prototyping needs for high-precision resistors. Several years ago the emphasis was mainly on fast delivery, so we set up a system that would allow customers the unique ability to get precision resistors with any specified resistance value out to six digits in a matter of days. Now customers aren’t just asking for fast delivery. They’ve also turned into electronic locavores of a sort and, like prudent customers everywhere, they want to know exactly where their components are coming from. Moreover they increasingly want the components used in prototyping to be manufactured as near to their R&D facilities as possible. In our case, we now provide a series of strategically located “express hubs” in the U.S., U.K., continental Europe, and India that provide what we like to think of as artisan resistor products that can be delivered in as few as five days and in just about any quantity. These hubs trim and mold precision resistors just the same as at VPG’s central locations but are located close enough to our end customers to enable the personal relationships, and up-close inspection of the product, just like traditional artisan producers. Beyond the added level of confidence this gives our customers, it’s also helping them to keep their R&D facilities local, which more and more companies are coming to value now that the disadvantages of trying to off-shore these activities have been clearly demonstrated.