prototype

To Prototype or not to Prototype?

May 2, 2016 by Adept Engineering Leave a Comment

Previously we spoke about 3D printers, their promise or lack thereof! I will admit I have been a bit cynical of their reliability, accuracy and actual usefulness. There is absolutely no doubt that 3D printers are here to stay and promise great things for our future. Sadly, for most of us, it still remains in the future. Despite the fact that Adept designs 100’s of parts per month we don’t own a 3D printer and don’t expect to purchase one anytime soon. That’s not to say we don’t utilize rapid manufacturing a great deal. However, by not bringing a single technology in house we are not bound or tempted to fit our process into the single technology we own. Prototyping companies put out a horde of advertising displaying complex assemblies that have been 3D printed in order to entice us towards their machines and services, but beware, (we’ll talk about that a little later). I don’t want to necessarily talk about 3D printers but more about prototyping as a whole. Specifically about when to prototype and when not to prototype, a sort of Shakespearean… “to Prototype or not to Prototype”.

After 30 years in Engineering and having lived the age of computerization within the engineering community, I remain awed by the capabilities and tools at our disposal. But like most facets of today’s technology, just because we can, doesn’t mean we should. What I’m referring to is the onslaught of decision making surrounding when and how to prototype. I’m not only addressing; Poly-jet, Stereo-lithography, ID Light, Laser sintering, Fused Deposition Modeling and Direct metal laser sintering, (I’m sure I may have missed a few), but one method that seems to have taken a back seat when discussing methods of prototyping. All these processes rely on the primary phase which they depend, 3D modeling. Even this is becoming easier, where there are freeware and online programs that help you create your ideas in 3D compatible formats enabling fabrication by one of these processes. However 3D modeling in of itself is a prototype. Which brings be back to the original question, when to prototype? Well, if you’ve already built a 3d model you already have.

Prototyping is a method of simulating an end result. In some instances these methods of prototyping are becoming methods of manufacture. As I wrote earlier about the GE

LEAP fuel nozzle being manufactured by Metal Laser Melting. Where a fuel nozzle of 17 parts was manufactured as a single assembled component or perhaps Solid Concepts fully functional 1911 semiautomatic pistol. I expect in our lifetime these methods of manufacture will become mainstream. But, as Solid Concepts points out, the fabrication of the pistol required experts using state-of-the-art equipment to produce it, not to mention countless man hours. So, the methods that are available to you and I will produce similar items, however they are still crude, inaccurate and unreliable. Simulation is a large part of Engineering, as is Prototyping. In essence all computer model simulations are prototypes. Prototypes that we don’t have to fabricate, can be easily modified, are incredibly accurate (often too accurate!) and can be destroyed repeatedly!

Computer models and simulations provide a perspective worth 100’s of prototypes. I remember hearing decades ago how Detroit used to make 100’s of prototypes of an automobile and now (20 years ago) they make 6. I expect that number has actually risen while the methods of engineering and manufacture have evolved and our tools are being used more effectively, efficiently and ingeniously put to use.

Prototype Development — Detailed Assembly

Computer simulations have come as far if not farther than rapid or additive manufacturing. An issue I take notice with, is the fact that rapid manufacturing has stolen the term rapid prototyping, because the fabrication process is only one piece of the puzzle and it happens to be a very costly one! Not to say that engineering hours are cheap, so there lies the quagmire! The cost to engineer and prototype is at the core of engineering decision making process. Assembling the correct engineering plan for the given project needs to be closely monitored and tailored to the projects near and long term objectives . Computer engineering/designing/modeling is at the forefront of the overall process. But the computer modeling element is not a one size fits all objective!? Because the rapid manufacture technologies available to the average machine or product developer are limited, your “prototyping” dollars must be carefully assessed and applied.

Every simulation or prototype has it’s objective and must be designed for that objective. Components slated for plastic injection molding are perhaps the simplest because the additive manufacture processes offer components in an array of materials that closely approximate real materials and the process yields similar tolerances. And, if these parts are structural, provided you select the correct material, process and align the grain direction appropriately you can yield a good simulated part. But remember you will have only one configuration to evaluate and to reevaluate you’ll have to purchase another prototype. If you require components of greater strength or tighter tolerances then it often pays to work your computer simulations further because your methods of rapid manufacture get more costly and time consumin
g. Clearly we can’t cover even a small cross section of considerations when it comes to when and how to prototype. But before you prototype be sure to ask your designer or engineer; “what is the objective of this prototype?”, “what will this prototype tell us, that we don’t already know?” and “how will this prototype move us closer and faster to our final objective, that can’t be achieve other ways?”.

Deciding when to prototype and when not, is a complex decision. Like most engineering decisions there are a host of considerations. Sometimes vested interest just have to see and touch what is being done. However first and foremost listen to your engineer, no matter how glassy eyed you may get as you listen to the decision making process, it is a process of trade-offs, filled with reason and rationale. And as you evaluate which simulations to perform and which to forego be sure to ask, what the risk are if we go with intuition, do we perform the analysis and to what level do we need to analyze. But always remember it’s expensive to build and cheap to modify computer models.

Regarding Your New Year’s 3D Printer Purchase Decision…

January 22, 2015 by Adept Engineering 4 Comments

Happy New Year! Please allow me to take this moment to thank you, our readers. We’ve enjoyed your comments and look forward to our exchange in 2015! In today’s post, we will be discussing 3D Printers.

Last year flew by in a flash, while this year commemorates Adept’s 20^th anniversary. It seem like just yesterday when we opened our doors to new and exciting projects. A lot has certainly changed in the past 30 years, notably, advances in computer technology coupled with its’ user friendliness has been nothing short of remarkable. Technology once reserved for the elite has quickly becoming mainstream. In 1985, most engineers were surfing the net through 14.4 modems, Creo was known as Pro Engineer and Solidworks was,… nonexistent. So many technologies have advanced, but one technology that has truly coming-of-age is Additive Manufacturing. It may also be familiar to you by its process name, Stereolithography or SLA. Although, Additive Manufacturing is accomplished through a vast number of processes today, not only SLA. Some of the processes are so dialed in they’re capable to fabricating jet engine assemblies.

In the late eighties, when 3D design was reserved for primarily defense contractors and multimillion dollar corporations, I was fortunate to be a one of the few at Sikorksy Aircraft. I can remember one afternoon while we were humming along on Caids, Cadra, Catia and Pro E, when a young company called “3D systems” performed a presentation about a new technology called Stereolithography (SLA). We were told that within hours we could hold in our hands a physical prototype of our 3D computer models. How cool was that?! We were then asked to envision a time in the not so distant future, when we’d be able to fabricate working production ready components by a similar process. In addition, we were also reminded that soon there will be no more drafting boards in our engineering department . Many of use recalled laughing at that too, and there extinction was already well underway, so the snickers were short lived.

Once the presentation ended, we went back to work thinking what if? As I further reviewed this technology, I couldn’t help notice that this vision although incredible was lacking a bit on execution. The material was fragile and the UV light made it brittle and unstable. I began to think that the technology had potential, but there were few real world applications. Additionally, we were still very distracted by the mere ability to conceptualize, design and visualize our ideas in 3D while creating views and cross sections in a blink of an eye. The things we take for granted today!?

A short time later, I was conceptualizing a composite transmission housing and it became obvious that management was having a difficult time visualizing what I was proposing. The 3D computer images were great but limited, particularly when the conference rooms were outfitted with viewgraph machines, white boards and mobile data storage was restricted to a 1.44 Mb disk! I soon realized this was an ideal opportunity to utilize SLA. With the presence of an actual physical model, management was delighted. T So ecstatic they requested 6 more to use for discussions with other stakeholders. This gave us the opportunity to try out silicon molding too. We ended up making a dozen or more polyurethane copies from a silicon mold of an SLA and they were a hit. Thirty years later, we still use SLA and other similar technologies to prove concepts and demonstrate ideas.

In the past, the utilizes and supplies needed to support SLA were costly and even toxic. Today, these capabilities are at our fingertips and can reside on our desktop, just like your simple ink jet printer. The 3D printers of today are certainly more user-friendly than the SLA machines of the past. Although, they’re a far cry from the “replicator” they can be pretend to be. Machines like the Cubify or Makerbot are certainly approaching the price point of an expensive television and it seems like anyone who can program a gantry is marketing a 3D printer, so buyer beware.

Buying a 3D printer is just like buying an inkjet printer, or is it?

Working with this technology for the past 30 years, I’ve got a good handle on its’ assets and limitations, or at least I thought…more about that later. With the latest 3D printer craze, I found myself becoming kind of a pessimist. Similar to the availability and simplicity of ink jet printing technology, it seems like everyone with a garage and time to spare is selling 3D printers. Salesmen convincing designers and inventors that they will be obsolete if they don’t join in the 3D maker movement. Like most sales pitches, I prefer to look behind the curtain. Many 3D printers I’ve seen sit idle or produce pre-modeled downloads of trinkets that end up in the bottom of someone’s desk drawer. Don’t misunderstand me, there are many seasoned designers and engineers with 3D printers and putting them to excellent use. However, the hard long hours that should be spent on engineering, analyzing and designing are sometimes replaced by producing poorly thought out prototypes while hoping it works. Good luck with that approach!

Perhaps if you’re James Dyson and have 15 years of patience to make 5127 prototypes, you can come up with a really cool vacuum. However, if James came out of his barn for a couple of days and did some research, he may have found that Sikorsky perfected a similar method for removing dust from air. Luckily, Sikorsky had no interest in vacuums, and the patent ran out by 1993. James also believes failure leads to success, but 5126 times? Come on Jim! I happen to believe sound engineering leads to success. Failure will happen, but success only comes by dissecting and understanding your failure and applying known engineering principles again, to reach the end game. And with that, the number of prototypes should remain in the single digits. The Auto industry is a prime example of this.

Additive manufacturing would’ve cut Jim’s barn time quite a bit. And, I am sure the Dyson Company is now outfitted with an entire division of additive manufacturing capability. Perhaps some FEA and CFD as well. However, with all its promise, additive manufacturing has its limitations and it’s important to understand each of the processes capabilities and limitations if you are truly to get what you need out of your prototype. With any manufacturing process, you must understand what it can do and what it can’t. As fun as it is to see your creation in real-time, the main purpose of making a prototype is to reduce risk. The risk resides in whether the virtual concept will accomplish it’s physical goals. Years ago, we were limited to fragile resins. Today, there is a range of materials and processes to choose from that are approaching real world properties. Even though, close attention must be paid to other component characteristics that will affect prototype performance, characteristics such as tolerances, surface finish, and manufacturability. Fortunately, the availability of rapid machining has given us additional capabilities to machine components in the intended material, thus further enhancing our ability to prototype. While it’s pretty cool when someone makes a working wrench or even a gun with a desktop 3D printer, don’t think that it happened overnight. The 3D models to accomplish such feats take a good deal of work to dial in.

There’s one company that is really raising the bar. If you have not heard, GE’s latest jet engine, known as the LEAP engine is using additive manufactured parts in production. Specifically, the fuel nozzle. Previously, the fuel nozzle required an assembly of 17 parts. With Additive Manufacturing the fuel nozzle is manufactured as a complete assembly! The rules of design are changing in a big way. “Look mom, no fasteners!” Even the lead Engineer of this project was not on board at its onset, but accepted the challenge like and good engineer would.. GE has spent the last 11 years advancing this technology in order to give the company the ability to accomplish such an amazing feat! Of course there are still issues, like the time of manufacture. It takes several weeks to grow 1 nozzle and expect there are multiple post processes too. But companies like GE are hot on the trail to improve this technology and reduce production times. Regardless, GE is committed to install 17 fuel nozzles in every LEAP engine it sells. With a 6,000 engine backlog at $78 billion, you can expect that GE incentive to realize the many benefits of this technology. Now, if you think you’re anywhere close to something like this with your Maker-bot, think again But get ready to see much more from Additive Manufacturing.

Did I say that it is a great time to be an Engineer! Thanks for reading.

Making Wise Prototype Decisions, Don’t Drink from a Fire Hose

July 10, 2014 by Adept Engineering Leave a Comment

In my previous post, I mentioned the responsibility of deciding when to transform a virtual prototype into a physical prototype. I may have been a bit premature having this discussion with my readers. As you may be aware, there is a great deal of hype – surrounding “desktop printing” and I may have jumped on that bandwagon a bit hastily. This technology has been around for decades. True, some very industrious individuals brought this technology main stream by offering desktop printers within a price point of a personal computer. However, before you get to play with this new toy, you must have a “solid model”. While there are many tools to create solid models, engineering or designing a solid model is a very different undertaking.

Before you consider going to a physical prototype, a clear understanding of the problem at hand is critical. For the engineer, this understanding is in the form of a specification document. Preparing and formulating a thorough specification requires capturing a client’s ideas, requirements and desires into a set of boundary conditions describing a system to satisfy their needs. It is up to the engineer to truly listen to an innovator’s visions and resolve them into a specification document..

The image above is the prototype of the Sigelock Systems vandalism proof fire hydrant.

Developing a specification document can be daunting. Do you think I am overstating this effort? I am immediately reminded of a client Adept helped several years ago. This client is an excellent example of a consultant’s worse nightmare and dream client all wrapped up in one package.

It was early in the morning, my phone rang and a gentleman introduced himself as George Sigelakis, a retired firefighter. He proceeded to passionately explain his idea for a revolutionary fire hydrant. The invention sounded like it might have merit. With genuine interest, I sat up in my chair and began to listen. He explained he worked with several other engineers and began making prototypes. While the prototypes were really close to what they needed, there was one problem, they don’t work!?

An installed Sigelock Fire Hydrant.

At that point, I began to explain my methods and what I think needed to be done. I was very direct and perhaps ended the phone call a bit prematurely. Fortunately, a week or so later, the phone rang and it was the same gentleman. He also felt our discussion was too short and called back to set up an in-person meeting to further discuss options together with his investor. This meeting revealed hand drawn prints, and miscellaneous parts along with a more detailed explanation of the vision at hand. There was no doubt this group was working on this project for several years and determined to bring this product to market. However, it was also immediately obvious the existing design did not meet their requirements. After hours of explanation and discussion, the client seemed assured I knew what I was talking about but still was not clear on why their design wouldn’t work. Concluding the meeting, I said I would analyze their existing design and prepare a report diagnosing the designs possibilities. They agreed. After reading the report they decided to ask Adept to provide a product redesign proposal.

Understanding a client’s needs is paramount to the success of any project. Fortunately George Sigelakis, the inventor of the Sigelock Systems, had a clear and precise vision of what his hydrant needed to be. Armed with clear direction and persistence, Adept was able to help establish the necessary guidelines (specification) to create the Sigelock hydrant.

There are many lessons to be learned from Sigelock Systems. One such lesson is sheer persistence. Staying the course is imperative to the success of any design. All design efforts are a conglomeration of ideas, people and resources. Perfectly coordinating all these elements requires diligence and often some luck. Along with persistence, decisions need to be made. Throughout the design and developement process there are no shortages of decisions. Some of the most important judgments come early on when the desire to “get moving” is very strong. These decisions can tend to be a bit rushed, at times. One of my favorite engineering cliches is, “there is never time to do it right, but there is always time to do it over”. This may be true for the United States government, but not for the product developer.

Did I say that it’s a wonderful time to be an engineer? The tools are nothing more than miraculous. I expect that this appreciation comes from the unique perspective of engineering from an era that went from the drawing board to the computer and beyond. The decision to leave the virtual world and enter the real world is similar to most engineering decisions. It is filled with trade offs, generally weighing the benefits from the risks. And, often the reason to stay virtual or go physical is to mitigate risk. Confused, you should be, because it’s not easy.

prototype

Footer