Tag Archives: optical medical products

Avoiding Design Stress Disorder

http://intellivex.com/news-and-events/data-center-events/monthcalendar/2015/12/-.html Outsourcing Product Development for Winning Products
Randal B. Chinnock

I swear at my toaster oven. Don’t get me wrong — it’s not the kind of thing I do to amuse myself on a Saturday night. It is the result of what I call “Design Stress Disorder,” a syndrome that arises as a result of poorly designed products. It starts with confusion: Am I using this wrong? Then comes self-denigration (Am I stupid?) followed by disbelief, irritation, and the urge to fling the offending object out of high windows. The toaster oven that I hate takes several minutes to heat and cooks so unevenly that it sears a black line across my toast while leaving the rest barely warm. For an encore, the rack falls out if something as heavy as a small Pyrex bowl of lasagna is placed on it. And it is ugly to boot.

You do not want your customers to develop Design Stress Disorder when they use your products. They will write you nasty letters and never buy your products again. So how do you avoid this manufacturer’s purgatory? Design your products right the first time, using the right tools and the right people. Part of this means using the best design software applications and people who are expert at using them. If you don’t have these tools and staff in your organization, outsource the work to pros.

The current generation of product design software is amazing. At the heart of most product design efforts is a mechanical computer aided design (CAD) program. The best CAD programs, such as SolidWorks, are called “solid modelers,” because they create extremely realistic 3-dimensional parts. The parts can be viewed at any angle, rotated, cut, and examined on the computer screen. They can then be mated with other parts to create an assembly. The assemblies can be analyzed to determine how they respond to mechanical stress, extremes of temperature, and dynamic effects such as shock and vibration. Plastic parts can be analyzed to determine how well they’ll mold, what residual stresses will remain in the part after molding, and whether the part will warp or deform from these stresses as it cools after molding.

If one part in an assembly is generating heat, these finite element analysis (FEA) programs can calculate how the heat is conducted and dissipated, and whether parts that people touch will get too hot. Not long ago, massive mainframe computers were required for these kinds of tasks. Now, they are performed on high-end desktop computers. This enables the manufacturer to learn all of this information before spending a nickel on making actual products.

In the case of the toaster oven, each of the toaster’s parts – the cover, door, bottom, sides, handle, rack, knobs – could then have been modeled, mated, and toleranced to ensure proper fit. The radiation pattern from the heating elements could have been analyzed to determine not only how uniformly the toaster will cook, but how hot the outside surfaces will become, heading off potential liability suits.

To ensure that a product meets user needs, performance requirements from user- and marketing-perspectives are captured in a Product Requirements Document (PRD). If this had been done, the maximum weight that the rack should support would have been defined. Then the rack, which is made of chrome-plated steel wire, could have been subjected to an FEA analysis, which would have quickly shown that it bent too much under a reasonable load, causing it to fall out of its guide slots. Along the way, mechanical engineers work closely with industrial designers to develop an aesthetically pleasing appearance and intuitive controls, as well as ensuring that the entire product can be manufactured cost-effectively.

Design defects can have much more serious results than a morning snit over burnt toast. In the medical field, products must be designed extremely carefully to ensure that they don’t fail during use and harm a patient or doctor. Failures can be caused by parts coming loose, by software or electronic circuits that go haywire, or by poorly designed controls that lead to operator error.

In the laboratory automation field, such as Hologic’s system for the automated processing of PAP smear slides to detect cervical cancer, complex systems with optical, mechanical, electronic, and software components must work together with great precision. If not, the resulting errors can be disastrous. False positives inflict patient anxiety, while false negatives can result in disease and death.

During the development of this system, we designed and tested the optical imaging components on the computer before any lenses were ground and polished. The mechanics were subjected to repeated actuations in an FEA program to ensure that precision was maintained after millions of cycles. We put the software through extensive “validation protocols” (testing) to ensure that incipient, undetected defects would “fail safe”, i.e., in ways that cause no harm. The results from these tests were used to modify the design while it was still in the computer, saving a lot of fabrication expense – and liability exposure.

Product Development firms offer manufacturers specialized expertise for creating safe, innovative, and profit-generating products. Such firms range in size from the solo designer to the 500-person full service giant. Some firms specialize in certain market segments, such as consumer products, while others are focused on industrial design; while still others – like Optimum Technologies – offer great engineering depth and can take on the analytical and design challenges of complex medical devices.

In choosing a firm, look for one that has experience in your field. They should understand the fabrication technologies involved in the manufacture of your product, and be able to work closely with your internal resources.

Avoid Design Stress Disorder. If product development is not a core competence of your firm, outsource to a firm that listens, understands your markets and goals, and can innovate all the way to the winner’s circle.

Optimum Technologies, Inc. is the northeast’s only full service product development firm specializing in optical medical devices and instruments. OTI’s FDA-compliant facilities are located in Southbridge, MA, and their staff has collective experience of over 500 years in the design, development, prototyping, and production of innovative products. Mr. Chinnock is the company’s founder and CEO. For more information, go to  www.optimum-tech.com

“Optical Medical Devices – Faster To Market”

Randal Chinnock discusses improvements in Rapid Product Development with 3D printing at MD&M East 2014

Randal Chinnock, CEO of Optimum Technologies
Customers show up all the time with their hair on fire. Their investors are pressing them to get products to market as fast as they can and they come to us and they ask, “How long will it take?” Even before a product has been designed, we have to find a way to answer that question. And one of the most important aspects of product development is getting parts prototyped as quickly as possible.

So we use computerized design tools for mechanical, optical, and electronic components. We then have a whole variety of rapid prototyping service providers that we can go to, who can turn around prototype parts in a matter of days.

Here at the 2014 MD&M East, I’ve been out talking to some of these service providers and manufacturers of rapid prototyping equipment to understand what the latest advances are.

Andrew Lubicello, Area Sales Manager – East of EOS of North America
One of the strengths of the DMLS is that you can combine multiple parts that used to be machined, MIMed, and then brazed together. You can make them all in one time, over and over and over again with not a lot of manpower. It’s basically a printer that’s printing in 20 micron layer thicknesses out of titanium, out of cobalt chrome.

This is an eye implant that if someone were in a bad car accident and had to reconstruct their face, they could print things with a mesh that will actually grow back bone. There are other parts being produced that are integrated camera parts, lenses, gears and so forth.

Randal Chinnock, CEO of Optimum Technologies
So as for mechanical parts, I found one very exciting vendor here: 3D systems. They have the latest generation of stereo lithography printers (SLA) and they’ve reduced their resolution now to 16 microns. So this is a sample part that they’ve produced. It’s a round part with a whole series of tiny vanes in it and some mounting features. This is not a part that could be produced by conventional machining methodology. This can only be produced by digital techniques.

Having this kind of capability available allows us to make mechanical parts that we can use, for example for a very precise a lens barrel, spacers and apertures that go into an opto-mechanical assembly into which we can load optical components.

Another supplier that we found is called ProtoCAM and they specialize in rapid prototyping using a variety of processes including urethane casting and that’s a very interesting process for us.

Chuck Hawley, Technology Manager of ProtoCAM
So we’ve been doing this for about twenty years and we’ve developed techniques throughout that time to make some very, very clear parts, both raw as well as urethane castings. So typically engineers will send us files, we’ll print them out in 3D, generally in stereo lithography, polish the daylights out of them, and then make urethane castings with temporary RTV molds. The end result, we can cast them in any color we want, but the clear, as I understand you’re interested in, we specialize in.

We make them for medical companies, displaying implant devices for doctors, and we’ve had great success with it. Our customers are very pleased with the results. We can do light tubes and other type applications of lenses or light conveyance mechanisms, bringing like say from the back of a VCR out to the front panel, where you’ve got your light in one place but you need to bring it to a different part of the mechanism.

Randal Chinnock, CEO  of Optimum Technologies
So we can use ProtoCAM’s urethane casting technology to make a variety of optical components, particularly in the illumination category. We can cast windows and light pipes that can be used to carry light from a light source to where the light is needed. It’s also possible that we may be able to work with a company like this to refine the process to be able to make optical components that are even accurate enough for imaging applications.

That would be the first time that any kind of casting technique could be used for that purpose. That would potentially cut many, many weeks out of the optical prototyping process and provide a much lower cost alternative to diamond-turning plastic optics.

But now we need another supplier that can make rapid castings that can be used to form an optical bench to hold a whole group of optical components. We found a company called Armstrong Rapid Manufacturing that has a process called one-shot casting.

Paul Armstrong, Director of Sales & Marketing of Armstrong Rapid Manufacturing
I wanted to talk about a new way to make metal castings quickly, where we’re able to take in a CAD file, 3D print up a Styrofoam master model, surround it with plaster, which then cures and we melt out the Styrofoam master, leaving a cavity of this shape that we can then fill with aluminum. Now this is Aluminum 356 Alloy, to a T6 heat treat, which will have the same properties die casting or other casting properties. We’re able to make it in a week. It costs us about $900 with no tooling.

Randal Chinnock, CEO  of Optimum Technologies
This will allow us to use this part to build assemblies and to perform a whole series of engineering verification tests that will be predictive of what an actual manufactured assembly would be like.

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