Innovations Creating a Buzz in Manufacturing World

Manufacturing Innovations

DEARBORN, Mich.—Earlier this year, the Society of Manufacturing Engineers (SME) released its 2013 list of "Innovations That Could Change the Way You Manufacture," shining the spotlight on five innovations that could significantly impact the future of manufacturing. Selected by SME's Innovation Watch Committee, the innovations are new and emerging technologies that have been successfully implemented and are making a difference in manufacturing today.

"While much of the tech world discusses the latest phone, computer, etc., the SME Innovation Watch Committee discusses what makes that new gadget possible," said Lauralyn McDaniel, manager of the Innovation Watch Committee, in a statement. "They don't stop at what we can do today, but look to what is possible."

The chosen innovations include manufacturing processes for insect-scale robotics and aluminum welding, as well as such advanced materials as carbon nanotubes and superhydrophobic coatings.

Robotic Insects Inspire Mass Production Technique

Monolithic fabrication of three-dimensional structures allows robotic insects to be mass produced by the sheet in a fashion similar to pop-up books and origami. Printed circuit MEMS (PC-MEMS) combines advanced materials and geometries of conventional manufacturing with one-piece construction micro-electromechanical systems (MEMS) below the submillimeter scale.

According to the Harvard Microrobotics Lab that pioneered this process, the printed circuit MEMS fabrication involves laser cutting complex patterns into thin layers of structural materials and adhesives. The layers are stacked in a line using precision pins. Heat and pressure bonds the layers together into a flat laminate. These laminates can be micromachined again, and combining both rigid and flexible materials allows the creation of mechanical structures with rigid beams and flexible joints. While fabrication allows the creation of complicated flat structures, pop-up folding and locking allows the assemblage of these structures into 3D machines similar to a pop-up book. A release step completes the machine by removing extraneous components.

Developed to solve manufacturing challenges in insect-scale robotics (weighing under 100 mg), PC-MEMS enables efficient manufacturing of a wide variety of similarly scaled machines at the mesoscale. The approach provides an alternative to conventional manual assembly, occurring today with skilled artisans, tweezers, and microscopes. While insect-scale unmanned aerial vehicles are a direct application, PC-MEMS could be used to create a wide variety of machines and mechanisms. With great advantage at the millimeter to centimeter length scale, the technique applies to a wide variety of advanced materials, including exotic metals, carbon and glass composites, plastics, and ceramics, according to the manager of the SME innovations program, Lora Lynne McDaniel.

The flat laminate relies on pop-up folding to achieve a 3D structure, and the "MoBee" monolithic bee designed by the Harvard lab uses nine interior linkages for 3D assembly. Six pins push on the top plate from underneath, separating the assembly scaffold plates to actuate the folding assembly. The entire device is submerged in liquid metal solder, which bonds selectively to the brass pads. This locking process allows MoBee to be removed from the assembly scaffold without unfolding. Finally, MoBee is released by laser cutting all connections from the scaffold and device itself. Then voltage is applied from an external power source, first at 1 hertz, then going to 30 hertz.

Printed circuit MEMS, according to the Harvard Microrobotics Lab, is a versatile process for creating machines at the millimeter scale. Capable of creating complex electrical and mechanical systems using a variety of techniques, the process is well suited to mass production, enabling the parallel manufacture of large numbers of robotic devices.

Superhydrophobic Coatings Could Save Mobile Phones and More

Nature has a way of solving difficult engineering problems. A beetle survives in the desert by harvesting water from fog that collects on its back and a lotus leaf stays healthy because of complex cleansing activities.

Sandia National Laboratories is working with super hydrophobic coatings by using surface roughness and chemistry to amplify water repellency. The lab has formulated a transparent solution that makes any surface super water repellent or super hydrophobic. According to Sandia Fellow, Jeff Brinker, there are many ways to make hydrophobic surfaces, but these alternatives mostly include specialized processing steps and vacuum treatments. They're also substrate specific or use many complex steps.

"What's unique about our material is it can be applied to any surface by simple spraying, dipping, or spin coating," Brinker said. "Using any common deposition approach, the super hydrophobic property develops immediately. And this is because our material is unique because as it dries, it expands upon drying, creating the necessary nanoscale porosity which is requisite for the hydrophobic behaviors."

Capable of being applied to any surface and complex geometries, the coating can also have nearly perfect optical clarity. Like the lotus leaf, the coating also has a self-cleaning effect. Applications include reducing metal corrosion even under highly corrosive conditions, avoiding biofouling of medical devices; preservation of monuments and buildings made of stone; reduction of energy needed to pump fluids in pipe networks; moisture or ice-resistant barrier for avionics; and protective coatings for cell phones, paint, furniture, and art, McDaniel explained. Lotus Leaf Coatings is a company that manufactures both superhydrophobic and hydrophilic coatings based on the work done at Sandia National Labs. Other companies, such as NeverWet and Nokia, are working on their own versions.

The process is exciting, Brinker said, because these super hydrophobic surfaces have fascinating properties. Water bounces and rolls on the surface, material can be cleaned from the surface, and the direction of flow of the droplets can be patterned. A growing list of applications for this film includes avoidance of metallic corrosion and icing on aircraft wings, and use as an additive to paint and other coatings to prevent mold and mildew.

Welding Process Increases Fuel Efficiency

General Motors (GM) has invented an industry-first aluminum welding technology expected to enable greater use of lightweight metal on future vehicles, thereby helping to improve fuel economy and driving performance. GM's new resistance spot welding process uses a patented multi-ring domed electrode that welds aluminum to aluminum by disrupting the oxide on the metal process. By utilizing this process, GM expects to eliminate nearly two lbs. of rivets from aluminum body parts, such as hoods, lift gates, and doors.

The welding process can be used for welding of aluminum sheet, extrusions, castings, or combinations, while also achieving high weld quality and eliminating surface expulsion. The rings of the electrode induce high levels of local strain on the outer surfaces of the aluminum to be welded, breaking down the hard, insulating, aluminum-oxide layer and enabling intimate contact between the electrode and aluminum, McDaniel explained. Based on standard resistance spot welding equipment and electrodes, the process allows the use of a common weld gun for welding either steel or aluminum, eliminating the need for material dedicated equipment. For the transportation industry, the process is said to provide a cost benefit of approximately $0.05 per joint over self-piercing riveting. This savings helps to offset the higher price of aluminum while providing strategic support of the new global CO2 emission targets taking effect in 2020 and 2025, she said. Automotive applications include aluminum closures and aluminum body structures, whether composed of stampings, extrusions, or castings. The process can also be used for welding applications in the truck, bus, heavy truck, rail, and aerospace industries.  

Stronger, Lighter, and Cheaper with Carbon Nanotubes

Carbon nanotubes (CNTs) are approximately 50,000 times thinner than a human hair with unique properties, including high electrical and thermal conductivity and outstanding mechanical properties. With a strength-to-weight ratio 117 times greater than steel, CNTs are the strongest and stiffest materials yet discovered, McDaniel said. More than 100 CNT manufacturers and more than 1,000 organizations are engaged in R&D.

With recent CNT price drops (from more than $1,000 a gram to as little as $50), applications are expanding rapidly. Commercialized products include step assists for GM, bumpers for Toyota, Wilson golf clubs and tennis racquets, Easton bicycle frames, and Samsung displays. Applications in development could improve energy use, from more efficient solar cells and batteries to actual power generation. Other applications in development include targeted drug delivery systems; artificial muscles for robots and prosthetic limbs; bone scaffolds; oil-spill cleanup processes; desalination filters; sensors that can detect chemical vapors or bacteria in drinking water; printable electronics; and flexible, transparent electronics.

True Color Detection with Rainbow Polymer

University of Buffalo engineers have created a rainbow polymer that can significantly reduce the cost and size of the current state-of-the-art multispectral analyzer from about $250 to $10 per piece. This one-step, low-cost holographic lithography method to fabricate a polymer with extraordinary properties is used as a filter for light. This material could form the basis of handheld multispectral imaging devices that identify the "true color" of objects examined, McDaniel said.

"The structures we are providing are called photonic bandgap structures," said Alexander N. Cartwright, professor in the Department of Electrical Engineering at the University of Buffalo. "It's very similar to what you see in very vibrant colored butterflies or peacocks. What we wanted to do was be able to have, within one film, a reflection of all different wavelengths. A sample made with pre-polymer syrup starts with a photo initiator, a co-initiator, a non-reactive solvent, a monomer, and some sort of reactive solvent. And in many of the things we do a liquid crystal component. When I shine a light on the sample, the photo initiator is excited and that photo initiator then actually transfers energy to our polymer mixture and creates photo polymerization. So polymer starts to form, but then we also put it under UV curing light, and this is critical so we can make these of any color and size. We can control many features of the film so we can get them optimized for the application we're interested in."

Accurate color detection, measuring spectral discrepancies in the nanometer range, has applications in anti-counterfeiting; remote sensing for military and defense applications; environmental, agricultural and climate monitoring; and microscopic bio-imaging. The graded photonic bandgap (PBG) structure could be easily coated on cell phone cameras to analyze the real color of food, medicines, paints, or cosmetics.

"It's an interesting, very applied research area that could have major economic impact in industry," Cartwright said.

Innovation Watch List

SME's Innovation Watch Committee also compiles an Innovation Watch List, highlighting technologies that are showing great promise, but, as yet, are unproven in the manufacturing arena. The following technologies make up this year's Innovation Watch List: