I remember the first time I saw a blueprint. It was during high school shop class where we learned how to use power tools to make the wooden chairs, tables, and chests shown in blueprints. I was completely confused. The odd paper and blue print, coupled with the liberal use of unfamiliar symbols, dashes and dots, and what appeared to be a mind boggling amount of detail was enough to start me in a cold sweat.
For many people, patent drawings are a lot like that first blueprint I saw. As a static two-dimensional (2D) representation of an operational device which is often complex, they present an immense amount of information on a page. The average person would be hard pressed to interpret them, and in fact, as we’ll learn later, they aren’t supposed to be able to.
We’ve been talking about patent basics in this series of blogs, and we’ll continue that discussion in the following weeks with a concentration on patent drawings. In the meantime, here’s one to ponder. When you look at a patent drawing like the one below, what do you see? What do you think this thing is and what is it supposed to do? We’ll find out next week…
Archive for the ‘Forensic Engineering’ Category
| When I was a kid I had a toy robot that captured my attention like no other toy. I thought it was so cool to have something animated that looked both humanoid and machine-like at the same time. It couldn’t do much, just walk in a stiff, jerky way and move its arms up and down, but that was enough to keep me fascinated.
Today’s generation of robots do not often take on the humanoid form, but they’re capable of so much more. Robots on assembly lines perform a variety of tasks like welding and placing electronic components on circuit boards, and they do it much more quickly and accurately than any human could, so they’re often employed in manufacturing.
We’ve been discussing the Production stage of the systems engineering approach to medical device design. We learned that within the manufacturing process there are often opportunities for cost reduction, and today we’ll see how robots can be used to reach those goals.
Last week we presented a sample scenario involving the manufacture of a percussion therapy device. In their quest to reduce manufacturing costs, engineers identified bottlenecks along the assembly line which led to idle worker time and the inability to keep up with orders.
In addition to these production woes, it was discovered that the tedious, repetitive manual labor that occurred at each bottleneck created opportunities for assembly mistakes. As many as 30 devices per day were being rejected by quality control inspectors due to issues such as faulty wiring and improper parts usage. This led to expensive rework to correct mistakes.
After further evaluation, design engineers determine that bottlenecks can be eliminated by installing automated assembly equipment in the three distinct assembly stages represented on the line, those involving wiring harnesses, printed circuit boards, and the motor drive mechanism.
The potential for human error is high during many facets of manufacturing, and this can be minimized or eliminated through the use of robots, that is to say, mechanized equipment capable of automatically performing a complex series of specific tasks. These robots never tire of performing tedious, repetitive work, and their efficiency is unparalleled. Their introduction at key junctures on the assembly line has benefits across the manufacturing process, enabling workers to keep continuously busy and reducing the incidence of human error.
The introduction of robotics is known as industrial automation. Robots efficiently increase manufacturing speed, and along with it profits, so their introduction more than compensates for the investment costs associated with purchasing them.
Next time we’ll continue our look at the Production stage to discover another way that systems engineering can simplifying the assembly process, by eliminating some functions altogether.
| We’ve been discussing the Preproduction aspect of the Development stage of our systems engineering approach to medical device design. Last week we learned that once the medical devices produced during Preproduction are assembled, they’re subjected to rigorous testing, first in the lab, then in the real world.
Once devices produced in Preproduction pass the test in a controlled laboratory environment, it’s time to place them into field testing. The objective is to place Preproduction devices within actual working environments, such as healthcare facilities. These facilities must be willing to cooperate with design engineers during testing on a number of items, including but not limited to evaluation of product performance and clarity of instructions.
In order for this to happen, design engineers must coordinate their efforts with their company’s sales and marketing departments to locate, qualify, and enlist suitable facilities. To qualify, a facility must be able and willing to put enough hours of use onto the test device to effectuate a thorough and complete analysis of its effectiveness. Depending on FDA regulatory requirements and the complexity of the design, field testing could take as little as several months or as long as several years.
During field testing valuable data is gathered to enable engineers to evaluate the performance of the Preproduction devices. This data will then be measured up against stakeholder requirements. What this process might entail in a dialysis machine, for example, is that test data is analyzed to make sure all operational parameters fall within the desired range. Data would be derived from measurements of such things as the pressure of blood flowing pre- and post- introduction to the dialyzer. Measurements are dutifully recorded by engineers and field personnel onto data sheets for later evaluation back at the manufacturer’s engineering office. Persons contributing data vary widely, from healthcare facility end users and maintenance personnel, to the medical device dealer’s service technicians.
End users also provide feedback to design engineers regarding the field test device’s functionality, effectiveness, reliability, and maintainability. Feedback can include specific information about things like glitches in software, unusual noises, erratic operation, breakdowns, and even difficulties encountered during repairs.
If any problems are discovered with the device during lab and field testing, revisions are made. Design engineers and technical writers get back to the drawing board to rework things and find resolutions until all issues have been addressed. Only then is the design presented to stakeholders for final approval. If all goes well, manufacturing will now take over and place the device into full commercial production.
We have now concluded our discussion on the Development stage of systems engineering as it relates to medical device design. Next time we’ll move on to the Production stage where we’ll examine post-production concerns.
| If you’ve been following along with our blog discussion on the systems engineering approach to medical device design, you should by now be convinced that instructions are important. In fact, the meticulous instructions produced during the manufacturing, operating, and maintenance phases of the Development stage are also crucial to later stages, that of Production and Utilization. Let’s finish up our discussion on the Development stage by taking a look at its final aspect, Preproduction.
The Preproduction aspect is instrumental to nipping potential problems in the bud before the medical devices go into actual production. In the initial Preproduction stages, systems engineers coordinate with the manufacturing and purchasing departments within the company as well as outside suppliers. The goal is to acquire all parts and equipment necessary to build a limited number of medical devices on the assembly line. Subjects such as preference in molded plastic components, motors, gears, pumps, springs, electronic components, circuit boards, wire, and tubing are discussed and agreed upon. Vendors are assessed with regard to their ability to produce parts when they are needed and that meet design specifications, satisfy quality requirements, and have costs that fall within budgetary constraints.
The assembly of Preproduction devices provides an opportunity for systems engineers to validate manufacturing and quality control instructions and assess the device design with regard to manufacturability, meaning, the extent to which devices can be manufactured with relative ease, at minimal cost, while maintaining maximum reliability. Devices manufactured during this aspect of the Development stage serve as a test. Are instructions clearly written? Do the device parts fit together as they should? Are parts strong enough to withstand the assembly process? Can the devices be assembled as quickly and easily as expected?
If the answer is “no” to any of these questions, then the device design and instructions must be returned to the design engineers and technical writers. Heads come together to rehash things and work out the bugs.
Next time we’ll continue with the Preproduction aspect of the Development stage to see how laboratory and field testing enables systems engineers to shake out any more bugs from the medical device design, operating instructions, and maintenance instructions.