Tag Archives: Mechanical Engineering

December 1, 2015

Yang: Harvesting more energy from photons

Yingyi Yang, a graduate student at MIT, along with other researchers at MIT, and elsewhere, have found a way to significantly boost the energy that can be harnessed from sunlight, a finding that could lead to better solar cells or light detectors. The new approach is based on the discovery that unexpected quantum effects increase the number of charge carriers, known as electrons and “holes,” that are knocked loose when photons of light of different wavelengths strikes a metal surface coated with a special class of oxide materials known as high-index dielectrics. The photons generate what are known as surface plasmons — a cloud of oscillating electrons that has the same frequency as the absorbed photons

The surprising finding is reported this week in the journal Physical Review Letters by authors including MIT’s Nicholas Fang, an associate professor of mechanical engineering, and postdoc Dafei Jin. The researchers used a sheet of silver coated with an oxide, which converts light energy into polarization of atoms at the interface.

November 18, 2015

yuk hydrogel superglue

Yuk: Hydrogel superglue is tougher than natural adhesives

Nature has developed innovative ways to solve a sticky challenge: Mussels and barnacles stubbornly glue themselves to cliff faces, ship hulls, and even the skin of whales. Likewise, tendons and cartilage stick to bone with incredible robustness, giving animals flexibility and agility. The natural adhesive in all these cases is hydrogel — a sticky mix of water and gummy material that creates a tough and durable bond.

Now engineers at MIT have developed a method to make synthetic, sticky hydrogel that is more than 90 percent water. The hydrogel, which is a transparent, rubber-like material, can adhere to surfaces such as glass, silicon, ceramics, aluminum, and titanium with a toughness comparable to the bond between tendon and cartilage on bone.

In experiments to demonstrate its robustness, the researchers applied a small square of their hydrogel between two plates of glass, from which they then suspended a 55-pound weight. They also glued the hydrogel to a silicon wafer, which they then smashed with a hammer. While the silicon shattered, its pieces remained stuck in place.

Such durability makes the hydrogel an ideal candidate for protective coatings on underwater surfaces such as boats and submarines. As the hydrogel is biocompatible, it may also be suitable for a range of health-related applications, such as biomedical coatings for catheters and sensors implanted in the body.

“You can imagine new applications with this very robust, adhesive, yet soft material,” says Xuanhe Zhao, the Robert N. Noyce Career Development Associate Professor in MIT’s Department of Mechanical Engineering. For example, Zhao’s group is currently exploring uses for the hydrogel in soft robotics, where the material may serve as synthetic tendon and cartilage, or in flexible joints.

“It’s a pretty tough and adhesive gel that’s mostly water,” Hyunwoo Yuk, a graduate student in mechanical engineering and the lead author of a paper on the work, says. “Basically, it’s tough, bonding water.”  Read more

October 3, 2014

robot fingertip sensor

Li and Yuan help design robot fingertip sensor

Researchers at MIT and Northeastern University have equipped a robot with a novel tactile sensor that lets it grasp a USB cable draped freely over a hook and insert it into a USB port. The sensor is an adaptation of a technology called GelSight, which was developed by the lab of Edward Adelson, the John and Dorothy Wilson Professor of Vision Science at MIT, and first described in 2009. The new sensor is small enough to fit on a robot’s gripper and its processing algorithm is faster, so it can give the robot feedback in real time. The researchers presented their results at the International Conference on Intelligent Robots and Systems this week. The MIT team — which consists of Adelson; first author Rui Li, a PhD student; Wenzhen Yuan, a master’s student; and Mandayam Srinivasan, a senior research scientist in the Department of Mechanical Engineering — designed and built the sensor.

September 26, 2014

Robot cheetah

Chuah helps build cheetah robot

Speed and agility are hallmarks of the cheetah: The big predator is the fastest land animal on Earth, able to accelerate to 60 mph in just a few seconds. As it ramps up to top speed, a cheetah pumps its legs in tandem, bounding until it reaches a full gallop. Now MIT researchers have developed an algorithm for bounding that they’ve successfully implemented in a robotic cheetah — a sleek, four-legged assemblage of gears, batteries, and electric motors that weighs about as much as its feline counterpart. The team recently took the robot for a test run on MIT’s Killian Court, where it bounded across the grass at a steady clip. Sangbae Kim, an associate professor of mechanical engineering, and his colleagues — research scientist Hae-Won Park and graduate student Meng Yee Chuah — will present details of the bounding algorithm this month at the IEEE/RSJ International Conference on Intelligent Robots and Systems in Chicago. Continue reading on MIT News.

September 22, 2014

Sun powered desalination

Wright and Winter work on sun-powered desalination

Around the world, there is more salty groundwater than fresh, drinkable groundwater. For example, 60 percent of India is underlain by salty water — and much of that area is not served by an electric grid that could run conventional reverse-osmosis desalination plants.
Now an analysis by MIT researchers shows that a different desalination technology called electrodialysis, powered by solar panels, could provide enough clean, palatable drinking water to supply the needs of a typical village. The study, by MIT graduate student Natasha Wright and Amos Winter, the Robert N. Noyce Career Development Assistant Professor of Mechanical Engineering, appears in the journal Desalination. Continue reading this article on MIT News.

September 4, 2014

Zhu assembles array of dynamic magnetic microhairs

MIT engineers have fabricated a new elastic material coated with microscopic, hairlike structures that tilt in response to a magnetic field. Depending on the field’s orientation, the microhairs can tilt to form a path through which fluid can flow; the material can even direct water upward, against gravity. Each microhair, made of nickel, is about 70 microns high and 25 microns wide — about one-fourth the diameter of a human hair. The researchers fabricated an array of the microhairs onto an elastic, transparent layer of silicone. “You could coat this on your car windshield to manipulate rain or sunlight,” says Yangying Zhu, a graduate student in MIT’s Department of Mechanical Engineering. “So you could filter how much solar radiation you want coming in, and also shed raindrops. This is an opportunity for the future.” Read the full article on MIT News.

December 18, 2013

Former MIT president Charles M. Vest dies at 72

Former MIT president Charles M. Vest — a tireless advocate for research and science, and a passionate supporter of diversity and openness — died last night of pancreatic cancer at his home in Washington. He was 72. As MIT’s 15th president, serving from 1990 to 2004, Vest led the Institute through a period of striking change and growth. A mechanical engineer by training, Vest was president of the National Academy of Engineering from 2007 until earlier this year.

During Vest’s presidency — the third-longest in the Institute’s 152-year history —MIT renewed its commitment to education and research through major innovations in both areas; developed strong ties with academic, government, and industry partners around the world; broadened the diversity of its people and programs; and transformed its campus with dramatic new buildings. MIT’s endowment nearly quadrupled during Vest’s tenure, growing from $1.4 billion to $5.1 billion.

“Through its own work, and especially through the lives and works of its graduates, a great university can strive to make the world well,” Vest wrote in 2004. “The knowledge we generate, the things we come to understand, and the devices we build can improve health, economies, security and the quality of life. MIT must continue to be optimistic in its vision of why we are here and what we can do.”

Continue reading the article on MIT News.

May 31, 2013

Tsai and Liggett (MechE) teach undergrads to make toys

Their theme might have been “in the dark,” but the MIT students who participated in this year’s 2.00b (Toy Design), a first-year elective in mechanical engineering, were anything but: Their creations ran the gamut from innovative board games to puzzles to stuffed animals to a comforter that transformed into a pup tent.

The toy prototypes were unveiled and demonstrated on campus Tuesday night before a large audience — including many children — armed with clipboards to score the varied offerings. Adding to the fun, each of the 16 teams of five students presented their invention as part of a five-minute skit — some featuring sound effects, costumes and choreography — followed by questions from the audience. The instructors and mentors who introduced each team did so with skits of their own.

Mechanical engineering graduate students Geoff Tsai and Lindy Liggett taught the class — which aims to teach basic design, building and testing processes — under the supervision of mechanical engineering professor David Wallace. “The goal is for students to get an experience they get jazzed up about,” Wallace says, and learn about “technology and tools they haven’t worked with before.” Read the rest of the article on MIT News.

December 11, 2012

Alumnus Henry receives $3.6 M to develop high-efficiency solar reactor

Researchers from the Georgia Institute of Technology have been awarded three grants totaling more than $9 million from the U.S. Department of Energy’s Advanced Research Projects Agency – Energy (ARPA-E) to develop energy technology solutions.  The three new awards are for projects involving solar fuel generation, power generation from vortices of solar heated air and energy storage.  Asegun Henry, assistant professor in the Woodruff School of Mechanical Engineering as well as MIT Mechanical Engineering alumnus (MSME and PhD) and MSRP alum, will receive $3.6 million to develop a high-efficiency solar reactor to produce solar fuel.  Using liquid metal, the reactor transports heat away from the sunlight-collection point to a chemical reaction zone, minimizing the loss of solar heat.  This system could enable cost-effective solar fuels that would be used for transportation and continuous electric power generation. 
Read the entire report in the Georgia Tech Newsroom.

November 26, 2012

Sanjay Sarma appointed as MIT’s first director of digital learning

Sanjay Sarma, the Fred Fort Flowers and Daniel Fort Flowers Professor of Mechanical Engineering, has been appointed MIT’s first director of digital learning, effective immediately.  In his new capacity, Sarma will work closely with the Institute’s faculty, staff and students to assess how new models of online instruction — such as the edX online-learning platform; MITx, the Institute’s course offerings on that platform; and other online tools that enhance students’ educational experiences — might become integral parts of MIT students’ on-campus education. These tools can also allow global learners access to MIT-quality instructional experiences. Read the rest of the article on MIT newsphoto by Bryce Vickmark

November 19, 2012

Ehrenberg discovers new metamaterial lens

In many respects, metamaterials are supernatural. These manmade materials, with their intricately designed structures, bend electromagnetic waves in ways that are impossible for materials found in nature. Scientists are investigating metamaterials for their potential to engineer invisibility cloaks — materials that refract light to hide an object in plain sight — and “super lenses,” which focus light beyond the range of optical microscopes to image objects at nanoscale detail. Researchers at MIT have now fabricated a three-dimensional, lightweight metamaterial lens that focuses radio waves with extreme precision. The concave lens exhibits a property called negative refraction, bending electromagnetic waves — in this case, radio waves — in exactly the opposite sense from which a normal concave lens would work.

For Isaac Ehrenberg, an MIT graduate student in mechanical engineering, the device evokes an image from the movie “Star Wars”: the Death Star, a space station that shoots laser beams from a concave dish, the lasers converging to a point to destroy nearby planets. While the researchers’ fabricated lens won’t be blasting any planetary bodies in the near future, Ehrenberg says there are other potential applications for the device, such as molecular and deep-space imaging. To continue reading the article, visit MITnews.

May 22, 2012

Team LiquiGlide

Team LiquiGlide Ends Violent Ketchup Bottle Shaking!

We’ve all been there. You get a bottle of Heinz ketchup from your cupboard or in a restaurant ready to dress up those fresh-cut fries. When you open it up, however, the bottle is nearly finished and you have to keep tapping the neck of the container to get the last bits to flow out. That, or you can keep shaking and pray the ketchup won’t end up everywhere. Instead, reseachers from Varanasi Research Group developed LiquiGlide, a non-stick coating for food packaging that will help substances flow out of the containers more seamlessly. Team LiquiGlide was bestowed the honor of the popular vote at the May 14th 100k finale presentation, with audience members texting their favorite pitch to the contest organizers to vote. The team, with Mechanical Engineering graduate students Dave Smith, Brian Solomon, Adam Paxson, and Chris Love, as well as postdoc Rajeev Dhiman and advisor Prof. Varanasi, was a WildCard Round winner and one of the 8 teams to make the final round. Read more and watch a ketchup video on digitaltrends.com.

April 25, 2012

Presidential Fellow Places Second in De Florez Graduate Design Competition

A joint entry by David Fenning (Presidential Fellow) and Doug Powell, the Impurity to Efficiency Simulator, won second place in this year’s De Florez Competition for the category of Graduate Design. The competition had 38 applicants in four categories, all of which competed against each other for a total of $18,000 in prize money. The categories were Undergraduate Engineering Design, Undergraduate Engineering Science, Graduate Engineering Design and Graduate Engineering Science. Applicants try to “sell” their products and judges look at the entries’ level of creativity, innovation, practical application, scientific basis and design skill. For more information and the full list of this years’ winners, please visit April 2012 MechE News.

October 15, 2011

MechE PhD Alumnus Norman Fortenberry Executive Director of ASEE

FortenberryDr. Norman Fortenberry, Mechanical Engineering PhD Alumnus ’91, and a longtime leader in education scholarship who has held senior positions at the National Science Foundation and National Academy of Engineering, has been appointed Executive Director of the American Society for Engineering Education.