MIT Research News' Journal

Using engineering savvy to improve product designs

When Edward (Ned) Burnell sees a design problem, he is always ready to find a better solution. Even while chatting with a journalist outside his office, he points out ceilings and windows in different spaces and describes how he would improve them.

For Burnell, a master’s student in mechanical engineering, thinking about design is a way of life; whether he is creating a novel windmill or improving engineering software, he enjoys using his skills to figure out innovative solutions to familiar problems.

Growing up off the grid

Burnell’s unconventional way of looking at the world can be traced back to his upbringing in Northern California. Burnell describes his childhood home in Mendocino County as “off the grid,” located in a remote area that had only dirt roads at the time.

“The town I grew up in actually is not even a town,” he says. “There's no municipal service besides the fire department. There is one gas station, one grocery store across from the post office, a Presbyterian church, and a K-3 school.”

Burnell was homeschooled by his parents until high school, when he began attending a nearby public school started by people in his community. His high school was different than most: Conventional desks and chairs were replaced by couches, and students could wander in and out of the main classroom in the center of school at any point during the day. Burnell enjoyed his school’s unusual culture and appreciated its focus on intrinsic motivation.

Finding his place at MIT

Burnell, who also has a BS in mechanical engineering from MIT, didn’t expect to attend such a large university, but during a visit he was immediately attracted to the vibe of the dorms in East Campus, such as the one where he lived previously, which he describes as wacky and a little bit punk.

“It's in this old bunker that has really thick walls,” he says. “Everyone just paints all over everything. It's like an old industrial district, safe because no one wants to mess with it.”

Growing up, Burnell hadn’t given much thought to what went into designing the products he saw around him — a finished bicycle, cup, or piece of furniture. As an undergraduate at MIT, however, he began thinking about the entire process of making products, and all of the decisions that lead to designing products in a particular way. This is what motivated him to pursue mechanical engineering.

“It was coming here and seeing, oh, there are actually all these ways in which these things do get made by people, and hey, I can be one of those people,” says Burnell.

As an undergraduate, Burnell also began thinking about how improving lesson design can help students learn more effectively. He traveled to Ghana, first as part of MIT’s D-Lab and later on a fellowship from MIT’s Priscilla King Gray Public Service Center, where he taught students hands-on engineering lessons. One particularly successful lesson involved guiding students as they built a battery to power an LED light, using basic materials such as copper wire, a bag of charcoal, a soda can, and salt water.

“These were very familiar objects,” he says. “We could've, on the walk to school, gotten literally all the products, and the fact that they did this really unexpected thing [made the students] really curious — students were in disbelief.”

Burnell also worked on creating an informal, interactive classroom environment where students were presented with open-ended projects that encouraged them to explore and ask questions, something they hadn’t previously experienced in their more traditional, fact-based British educational system.

Improving existing designs

Before returning to MIT for grad school, Burnell spent a year working at Makani Power, a company in Almeda, California, that is developing innovative approaches for harnessing wind power. Burnell’s project involved taking the conventional windmill design, a tower with a giant wind turbine on top, and changing it to make something better suited to the environment.

“With this turbine you have a tether, so it's like a kite. It's much smaller; you have a plane flying, and you have little propellers on it that slow it down, and it's just gliding around. It sounds like an insect and looks kind of like a bird,” he says. “Two people could carry it, and it would make about 20 kilowatts an hour, so that [could power] about 10 houses, in a 20-mile-an-hour wind.”

As a grad student at MIT, Burnell has continued to work on projects that improve existing designs. Last year, Burnell took part in MIT’s Assistive Technologies Hackathon, where he and his team designed a better version of a tool called a “sip-and-puff joystick.”

People with cerebral palsy or muscular dystrophy diseases often don’t have the hand precision required to manipulate a conventional computer mouse or smartphone screen, but they are able to control the position of their mouths. The sip-and-puff joystick is a medical device with a mouthpiece that responds to sips and puffs of air, which are translated into different actions on a computer or smartphone. However, because conventional sip-and-puff joysticks are designed for hospital use, they tend to be large and overbuilt, with poor portability and limited battery life.

Burnell and his team decided that they could improve on this design to make something more useful for everyday life. Their version, the Puffin Joystick, was created in collaboration with Adriana Mallozzi, who has cerebral palsy and has used many different technologies over the years. It consists of a mouthpiece attached to a minimalist waterproof tube that can easily be clamped onto any chair and repositioned as needed. It also has a long battery life and is cheaper than other versions.

Currently, Burnell’s research focuses on improving existing engineering design software. One project involves testing design programs that are used to solve structural problems. In the standard Computer Assisted Design (CAD) program, an engineer draws a structural design and hits a button to analyze it, at which point she can see every piece of the structure, color-coded based on how stressed it is. Burnell changed the program so every time a beam is resized, the program automatically redraws the structure, rather than requiring the engineer to click a button.

Burnell explains that this research aims to answer basic questions about the design of these programs, such as “How much does [a modification to the program] change not just how good your designs are, but how much you actually explore? Are you more willing to try something a little bit different, or, with a more frustrating tool are you more likely to just say, ‘Alright, this is good enough?’”

He is hoping that simple changes to the software will encourage engineers to spend more time exploring and thinking in novel ways during the design process.

Options for the future

Burnell is planning to pursue a PhD in mechanical engineering, though he is keeping an open mind about his future, since in his experience, “Generally things just pop up.” However, no matter where his life takes him, he is determined to use his engineering and creative thinking skills to continue improving the world around him.

“I think a lot of change happens just because people start having higher expectations. They start asking for more and saying ‘this [design] is good, but it's not good enough for me,’” Burnell says.

Scientists observe supermassive black hole feeding on cold gas

At the center of a galaxy cluster, 1 billion light years from Earth, a voracious, supermassive black hole is preparing for a chilly feast.

For the first time, astronomers have detected billowy clouds of cold, clumpy gas streaming toward a black hole, at the center of a massive galaxy cluster. The clouds are traveling at speeds of up to 355 kilometers per second — that’s almost 800,000 miles per hour — and may be only 150 light years away from its edge, almost certain to fall into the black hole, feeding its bottomless well. The observations, published today in the journal Nature, represent the first direct evidence to support the hypothesis that black holes feed on clouds of cold gas.

The results also suggest that fueling a black hole — a process known as accretion — is a whole lot messier than scientists had once thought.

“The simple model of black hole accretion consists of a black hole surrounded by a sphere of hot gas, and that gas accretes smoothly onto the black hole, and everything’s simple, mathematically,” says Michael McDonald, assistant professor of physics in MIT’s Kavli Institute for Astrophysics and Space Research. “But this is the most compelling evidence that this process is not smooth, simple, and clean, but actually quite chaotic and clumpy.”

Given the new observations, McDonald says black holes probably have two ways of feeding: For most of the time, they may slowly graze on a steady diet of diffuse hot gas. Once in a while, they may quickly gobble up clumps of cold gas as it comes nearby.

“This diffuse, hot gas is available to the black hole at a low level all the time, and you can have a steady trickle of it going in,” McDonald says. “Every now and then, you can have a rainstorm with all these droplets of cold gas, and for a short amount of time, the black hole’s eating very quickly. So the idea that there are these two dinner modes for black holes is a pretty nice result.”

McDonald is a co-author on the paper, which was led by Grant Tremblay, an astronomer at Yale University.

Seeing shadows

The researchers made their detection using the Atacama Large Millimeter/submillimeter Array, or ALMA — one of the most powerful telescopes in the world, designed to see the oldest, most distant galaxies in the universe. The team focused ALMA’s telescopes 1 billion light years away, on the central galaxy in the Abell 2597 Cluster, a galaxy that is some tens of thousands of light years across. This particular galaxy is among the brightest in the universe, as it is likely producing many new stars.

The team originally wanted to get a sense for how many stars this cluster was churning out, so they mapped all the cold gas within the cluster. This cold gas has cooled and condensed out of the diffuse halo of hot gas surrounding a cluster, forming clumps. It is the collapse of cold gas that creates new stars, especially in the cluster’s central galaxy.

“In the center of a cluster, there’s a single massive galaxy, the big daddy galaxy of the cluster,” McDonald says. “It’s sitting at the bottom of a gravitational funnel, and all the gas from a thousand galaxies is available to it. These are the galaxies that are the most massive, with the most massive black holes in the universe, and the most potential for star formation.”

The researchers used ALMA to map the spectral signatures, or radio emissions, from the galaxy cluster, looking specifically for signatures of carbon monoxide, the presence of which usually indicates very cold gas, of minus 200 degrees Fahrenheit and below. They mapped carbon monoxide across the entire galaxy cluster and found that as they looked further into the cluster, they encountered progressively cooler gas, from millions of degrees Fahrenheit to subzero temperatures.

At the very center, just at the edge of the cluster’s supermassive black hole, the researchers discovered something quite unexpected: the shadows of three very cold, very clumpy gas clouds. The shadows were cast against bright jets of material spewing from the black hole, suggesting that these clouds were very close to being consumed by the black hole.

“We got very lucky,” McDonald says. “We could probably look at 100 galaxies like this and not see what we saw just by chance. Seeing three shadows at once is like discovering not just one exoplanet, but three in the first try. Nature was very kind in this case.”

Richard Mushotzky, professor of astronomy at the University of Maryland, says the results prove that seeing is better than simply believing.

“In astronomy and astrophysics, there are a lot of good ideas out there likely to be true, but it’s important to prove they’re actually true,” says Mushotzky, who did not contribute to the paper. “That’s the big deal here. We believe [cold gas fuels black holes], it fits the models, but it’s much different to actually know than to believe.”

A high-energy feast

The team estimated the velocities of the three clouds to be 240, 275, and 355 kilometers per second, with all three headed toward the black hole. McDonald says these three cold gas clouds will likely not stream straight into the black hole but instead be absorbed into its accretion disc — the massive disc of material that will eventually spiral into the black hole.

He adds that while ALMA was only able to see three clouds of cold gas near the black hole, there may be even more in the vicinity, setting the black hole up for quite a feast.

“We’re only seeing this tiny sliver,” McDonald says. “If there are three clouds in just our line of sight, there might be millions of clouds all around. And there’s a tremendous amount of energy in just these three clouds. So if we were to look at this thing a million years later, we might see that the black hole is in outburst — much brighter, with more powerful jets, because all this high-energy material is landing on it.”

“ALMA has only been working for three years, turning on slowly,” Mushotzky adds. “It’s a very big and complex instrument, and this is very early data, but already things are turning out to be very exciting.

This research was funded, in part, by NASA, the European Research Council, the Natural Sciences and Engineering Research Council of Canada, and the Science and Technology Facilities Council.