SME Speaks: SME Forms Bioengineering Tech Group
Manufacturing engineers have been employed for decades to manufacture medical devices, working with biomedical product design engineers and physicians. In 1973, I was a tool and mold designer for a small medical company that molded and extruded medical-grade silicone rubber. We manufactured disks to be placed in the cages of human heartvalve assemblies, blood-puncture sites, blood-tubing sets with plastic luer fittings, implantable cannula blood-connecting tubes for kidney dialysis machines, and kidney-dialysis filters that used medical-grade PVC tubing. The company also manufactured battery-operated portable blood-infusion roller pumps and blood-bypass pumps to be used in heart surgery. Originally, the company manufactured hydrocephalus valves, which relieve excessive fluid within the cranium.
While Dr. Willem J. Kolff, his son Dr. Jack Kolff (a Temple University professor of surgery), and Dr. Robert Jarvik, along with many others, were inventing an artificial heart, my company manufactured a blood filter, originally invented by Dr. W.J. Kolff. Made of cellophane tubing wrapped around a cylinder in a bath of fluid, the filter was used to cleanse the blood of patients suffering from kidney failure. Blood from the patient travels through the cellophane tubing, with the toxins passing through the cellophane tubing membrane into the cleaning bath, until a point of equilibrium of the toxins is reached. Each time the cleaning bath solution becomes equalized it's changed to allow more toxins to travel through the cellophane membrane. The company also molded implantable silicone-rubber covers for pacemakers. Such covers are no longer needed, because of the recent use of laser-welded titanium containers for the implantable cardiac pulse generator. When sterilized, such containers will not be rejected by the human body.
Since the early 1970s, bioengineering and research has blossomed into a multibillion- dollar industry, with a great need for many engineers with different fields of expertise. Persons finding careers in bioengineering and research include manufacturing engineers, doctors, and technicians, who are responsible for producing many different products, such as hearing aids, operating-room equipment, pharmaceutical products, and much more.
During my tenure as a SME Membership Consultant for 10 student chapters, I found that the students were not as interested in mechanical engineering, manufacturing engineering, or machine-tool-manufacturing careers, but have a new focus in bioengineering, ergonomics, medical devices, pharmaceuticals, tissue manufacturing, development of new materials, TV integrated circuits, or new medical procedures, such as swallowing a camera pill or robotic surgery. Because of this increased interest, members of SME's Manufacturing Education & Research Community recently helped us to form the Bioengineering Tech Group.
The Bioengineering Tech Group seeks to support educational and research programs and individuals who are involved in bioengineering through:
- Promotion of biotechnologies and related design and manufacturing-engineering activities.
- Promotion of research through small-scale research-initiation grants.
- Organization of an annual bioengineering conference that relates to design and manufacturing-engineering fields.
- Capturing and maintaining interest of K-12 students by various bioengineering-related activities, curricula, and scholarships.
The tech group is chaired by Arif Sirinterlikci, PhD, director, engineering laboratories and associate professor of engineering at Robert Morris University (Moon Township, PA). Sirinterlikci is also the advisor for SME Student Chapter S334, and was recruited by me to be the chair of the tech group.
According to World Wide Learn, the Federal Bureau of Labor Statistics counted about 7600 bioengineering and biomedical engineering jobs in a recent survey. The greatest number of bioengineering specialists work in manufacturing industries, such as pharmaceutical, ergonomic manufacturing, medical-instrument development, and health-care supply. Many others work for hospitals, government agencies, or as independent contractors or consultants.
These types of jobs are expected to increase by nearly 32% over the next five years. Through the next decade, experts predict that bioengineering positions will increase at nearly double the average growth rate for all other types of jobs. An aging population with a focus on health issues has increased the demand for better medical devices and equipment. Coupled with this long-term trend is an industrial concern for cost efficiency and effectiveness. Achieving these goals requires the talent of biomedical engineers (World Wide Learn, 2008).
The workforce pipeline is currently at risk because of the misconceptions about manufacturing, i.e., manual labor and assembly lines versus high-tech innovative careers (Industry Week, 2007). Please take the time to become more involved in the Society and its mission, not only to disseminate technical knowledge, but also to encourage manufacturing education and manufacturing as a career choice. Visit www.sme.org/bioengineering to learn more.
About the Author
Lee Loeb has been a SME member since 1989. He has been actively involved in the Society through several key leadership roles, among them SME Philadelphia Chapter 15 secretary, chair, and nomination committee chair, and as an SME membership consultant. He is one of the original founders of the Bioengineering Tech Group. Loeb is currently serving as a membership ambassador to Chapter 15. He was recently honored with a 2008 SME Award of Merit. Loeb is the owner of LHL Design & Drafting, as well as a part-time machine shop instructor at Delaware County Community College.
Innovations That Could Change the Way You Manufacture
Direct Digital Manufacturing
By Carl Dekker
Sugar Grove, IL
Direct digital manufacturing (DDM) has already changed the way some products are being manufactured, and with this technology the possibilities grow every day. The opportunities for DDM exist where design constraints, process repeatability, and material properties overlap. This window has grown much larger and continues to grow with advancements. Factors supporting this growth include the advancements in machines and materials and increased competition that has brought down the cost of products and developments that now put the supercomputer capabilities of five years ago on the desktop.
As defined by the Direct Digital Manufacturing Tech Group, which is part of SME's Rapid Technologies & Additive Manufacturing Community, DDM is the process of going directly from an electronic digital representation of a part to the final product via additive manufacturing.
Additive manufacturing is the process of creating a physical object through the selective fusion, sintering, or polymerization of a material. A part is first designed on a computer, resulting in an electronic digital format. This digital part design yields information to direct the operations of the additive manufacturing machine to control the layer-based deposition and processing of materials. This direct nature of the process means that parts and products can be produced without tooling. Additive manufacturing can also enable the creation of parts and products with distinctiveness, which traditional manufacturing processes cannot do. This performance allows for greater complexity, freedom in design, and increased flexibility in the features and function of the end product.
The technologies that are used for DDM are those that were once called rapid prototyping, but these are not the processes of 10 or even five years ago. Technology and materials have changed tremendously. Now you can use additive manufacturing to manufacture within a realm of repeatability with materials that are stable. What is going to happen to that material in six months, two years, or more is now known. Many people still remember the days when materials were seen as fragile and unpredictable. You just did not know what would happen with them. Those who have figured this out are the ones finding great success with DDM.
You may have heard of technologies called stereolithography, fused deposition modeling (FDM), laser sintering, 3-D printing, direct laser deposition, or others. Whether using laser, electron beam, extrusion, or jetting to control deposition, all of these technologies are currently being used for DDM. Depending on the machine, materials are available in several forms, including liquid, powder, sheet, and filaments. Many of the materials available today are common engineering materials. Some have even benefited from nanotechnology to enhance mechanical properties.
Based on its strengths and limitations, potential applications for DDM can be divided into four basic areas, two of which are outlined below.
Area 1, noncritical and simple, includes applications that have nominal material requirements, do not have a defined safety requirement, and usually require some sort of uniqueness that makes mass production or traditional manufacturing too expensive and/or too slow. Chrysler used stereolithography and Magics Rapid Fit software to design and build a collection of support posts for a component to sit on a standard base during quality control. This allowed each component tested to be held at a consistent height during the process for repeatability during quality control. Stratasys has used its own system to manufacture the head assembly for the P class machines. Others have created guides as assembly aids or for quality control of placement of labels.
Area 2, noncritical and complex, consists of applications that tend to have unique designs that cannot be produced in any other way. They can also be ones that are customized designs and are often multifunctional. This is also the area that has some of the most visually interesting examples. Artist Bathsheba Grossman has produced many pieces that seem to define manufacturability using laser sintering of powder metals. Freedom of Creation (FOC) has become known as an innovative design company by harnessing the new design paradigm to create a line of art and household items, including unique lighting fixtures and furniture. Working with the Rapid Manufacturing Group at Loughborough University in the United Kingdom, FOC has also used laser sintering to create fabrics for apparel and accessories. Stratasys has used FDM to build a cradle to hold an injection-molded part that had extra wall stock and needed to be modified. This cradle allowed them to stay in production while the part was redesigned. Production aids have also been created for voltage-resistance product validation, providing for no damage to the assembly, ease of access, and passing quality control.
More information on DDM will be included in the May issue of Manufacturing Engineering or visit www.sme.org/ddm.
This article was first published in the April 2008 edition of Manufacturing Engineering magazine.