Home Store Project Ideas Project Guide Ask An Expert Blog Careers Teachers Parents Students

Recently in Interviews


What can engineers learn from studying the ways in which bugs and insects move? A great deal! Robotics labs like the Harvard Microrobotics Lab are using bio-inspired research and observation to design and test new approaches to designing and building small robots. Meet a female engineer working in the lab. She may not be keen on bees, but when it comes to coin-sized bots, she is excited by the challenge of taking what insects already do well and creating better, faster, and more efficient microrobots.

Dani Robotics Engineer
Above: Dani Ithier, Harvard student and engineer in the Harvard Microrobotics Lab

Flying Smart with Butterfly Wings

Dani's lab is using bio-inspired research to further robotics design and engineering, but other fields, too, study bio-systems to help improve existing systems, technologies, and understanding.

In the "Butterfly Wings: Using Nature to Learn About Flight" aerodynamics project, students make model butterflies to explore how changes in the angle of a butterfly's wing, relative to the wind, changes the lift force of the wing. Insect-inspired research may inform robotics design, but as this project shows, this research can also help address science questions and improve designs in other areas!

Like many kids, Dani Ithier grew up interested in building things. Popular engineering-inspired building and construction systems like LEGO are often a child's first introduction to the world of engineering. These systems provide an accessible, colorful, fun, and extensible platform that invites kids to explore engineering design and encourages troubleshooting and a step-by-step approach—for fun.

Kids who grow up building and tinkering grow up loosely using and enacting principles of the engineering design process. While these systems play a key role in facilitating childhood creativity and innovation, many kids outgrow their interest, snap-together building blocks and circuit kits being replaced by other activities and hobbies. For girls, the drop-off rate in interest in engineering toys may be even more dramatic.

Luckily, there are female engineers like Dani whose interest never wanes. She started out building, and she hasn't stopped yet.


Supporting Student Engineers

Thanks to support from her family, Dani's childhood passion was nurtured and encouraged. Today, she is applying, exploring, and expanding her interest as part of her undergraduate studies at Harvard where she works in the Harvard Microrobotics Lab, an electronics and robotics lab that specializes in research related to microrobots inspired by real-world bugs and insects.

"Growing up, support from family, friends, and teachers really helped me get more involved and excited about engineering and math and science in general," says Dani. "I had always been interested in building things, and my family encouraged me to do so despite the fact that they had no engineering or technical knowledge. They would buy kits for me where I would get to build model engines or play with magnets and circuits, and my uncle would hang out with me on weekends and teach me how to use power tools." In addition to lots of great engineering projects and kits at home, Dani participated in summer programs that let her continue to explore engineering and robotics.

At school, Dani says her teachers helped encourage and feed her interests by giving her extra challenges to work on, by helping as mentors in the after-school robotics program, and by making her aware of opportunities like the BAE System's Women in Technology Program. Dani was fortunate to have strong support, support that extended beyond the boundaries of in-class curriculum. "These opportunities helped compensate for what I saw as a lack of hands-on [science and engineering] activities in classes at school," she recalls. "We had lab periods in school and did several projects, but not nearly the amount I would have hoped for. I think it was really important for me to work on projects out of class to help me learn."


Making Room for Girls in Robotics

Programs and clubs like FIRST® robotics are often integral for students like Dani and help support the engineering spirit during middle and high school years. Dani recalls doing summer programs devoted to LEGO® Mindstorms, but she cites her participation in FIRST robotics as a powerful force in her development as a young engineer. As a young woman, however, her four years in robotics club also highlighted the disproportionate number of girls pursuing engineering by the time high school rolls around.

"There were very few girls on the robotics team I participated on in high school," admits Dani. "Over my four years on the team, only a handful of us actually participated in designing and building the robot." Though she categorizes the gender imbalance as discouraging, her team was fortunate to have a female mentor, which gave her and other teammates a role model and source of inspiration. Even so, "I do wish more women were encouraged to be involved in the sciences and join teams like robotics teams," says Dani.

The relationship between gender and engineering that Dani saw play out in robotics club is something she has continued to see in her college studies. "By looking at the demographics of the classes I'm in, the professors I've had, and the make-up of the engineering-related extracurriculars I'm involved in, I do feel like robotics and mechanical engineering are male-dominated fields. Often, I am one of the few women and people of color in these spaces."

Dani working in HAMR robotics lab
Above: Dani at work filming robotics testing in the lab—under very bright light conditions!

Microrobots to the Rescue

The miniature robots being built and tested in the lab may be used in a range of current and future applications. Search and rescue and exploration of environments unsafe for humans are areas Dani notes are particularly relevant to her lab's research.

"Many lives could be saved in the future," says Dani by way of example, "if, instead of sending humans into dangerous places, such as toxic areas or debris-ridden buildings after natural disasters, robotic bugs were sent instead!"

Students can explore robotics with a search-and-rescue mission in the "Robots to the Rescue! Build & Test a Search-and-Rescue Robot" Project Idea. The robot in the project involves a toy radio-controlled car, so it is many times larger than Dani's robots in the Microrobotics Lab, but the Project Idea lets students get started thinking about and testing important issues related to using robots in this way.

Given the numbers, finding female mentors and teachers becomes even more important for young female engineers. "I have found numerous amazing mentors I identify with who have advised me and made my experiences much more positive," says Dani. She also says she feels like she is seeing a change, an upward trend in the number of girls who are interested in engineering fields. This may be due to increased attention to science, technology, engineering, and math (STEM) education and, specifically, the desire to engage more girls in STEM.

"While things are getting better, I think these fields have a long way to come in terms of gender, racial, and class balance and that awareness of this and outreach are important steps to start changing this."


Inspired by Insects

Dani isn't a fan of cockroaches or bees and says she really would not want to work on projects that involve handling or close observation of either. But, in fact, Dani's work at Harvard centers on the design and development of robotic insects, robots inspired by the biology of other creatures. "Our lab models much of our work off of organisms and structures that already exist in nature. Why try to recreate the wheel when you can look at something that works amazingly (which so many things in nature already do) and mimic it to obtain good results," Dani explains. "Plus, it's fun to work with bugs and try to learn from them!"

Taking their cue from nature, Dani explains that research teams in the lab are working on both flapping-wing and ambulatory microrobots—bugs that fly and bugs that crawl. Both approaches to mobilizing a robot have different challenges. "Because both types are on extremely small scales (about the size of a quarter or smaller), mass is a huge issue," says Dani.

"Ambulatory robots need to remain light so that their transmissions are able to provide enough force for the robot's legs to lift the body's mass," explains Dani. "Flapping-wing robots need to remain even lighter so that they are still able to fly. This makes it difficult to put power supplies on board (batteries are heavy!)." Flapping-wing robots also present challenges for navigation and orientation systems, notes Dani. Flying bots have "lots of complicated control and sensor challenges because the robot needs to know its orientation in air so that it can continue flying under control."

Though cockroaches are not her thing, Dani has been working on a current version of the Harvard Ambulatory MicroRobot (HAMR) that models the design of a cockroach and is about the size of a quarter. Having worked on both ambulatory and flapping-wing robotics projects, Dani says she especially enjoys exploring the kinds of design issues and questions raised by ambulatory robots.

"I think I prefer ambulatory robots because I'm not particularly interested in fluid dynamics or control, which is what a lot of the work on flapping robots is. Rather, I like thinking about the dynamics and locomotion of ambulatory robots. For example, how does the leg gait affect how the robot moves, what kind of leg designs will allow the robot to climb walls, will changing leg materials increase speed?"

In addition to tackling challenges related to the physics and engineering of ambulatory microrobots, Dani says size is always an added variable and consideration. "It is hard to put things in the right place at that scale!"

The size may make building these robots a challenge, but it also makes things interesting when it comes to keeping track of them. With robots the size of a coin, it seems inevitable that they might wander or scuttle away, out of sight, or under something, never to be found again. But Dani says it hasn't happened. "Fortunately we have not lost any bots so far! It can be difficult though," she admits. But what do engineers do when things are difficult? They find solutions!

"With the ambulatory robots I'm currently working on, we put up little 'guard-rails' on the table that it walks on for experiments to make sure that it doesn't run off," explains Dani. "We also are pretty careful about keeping track of the robots when we are done using them and putting them in the drawer we keep them in."

To further help them keep track, Dani says the engineers give the robots names. "Currently we have Elle, Manny, and Actin."

Once they have a name, they are less likely to get overlooked during a daily robot roll call!

HAMR Micro Robots
Above: samples from HAMR research and development. Image: Courtesy, Harvard Microrobotics Laboratory. To see HAMR robots in action, watch this video.


Supporting Student Interest in Engineering, Robotics, and Computer Science

February 16-24, 2014 is Engineers Week, and February 20 is Girl Day (formerly "Introduce a Girl to Engineering Day").

Help excite your students—male and female—about engineering and introduce them to what engineering means and what engineers do. Students like Dani are quick to credit the support of teachers, family, and programs that help enable student exploration. The following resources contain ideas, projects, and links that can help kickstart student interest and exploration—you don't have to be an engineer, a programmer, or a robot designer to help your students pursue their own interest!



Science Buddies Project Ideas in Robotics are supported by Symantec.

Motorola Solutions Foundation, a sponsor of Engineers Week, is a supporting sponsor of Science Buddies.

Categories:

 

Jeff Hagen / Science Career profile

Jeff originally considered a career in electrical engineering but followed his interests into computer science. Today, he's an Engineering Manager at Medtronic and works to help oversee testing on CareLink, a heart monitoring site.

Meet Jeff Hagen, an Engineering Manager at Medtronic for the last nine years.

Jeff Hagen leads a team of software verification test engineers who deploy specific web-based applications that medical personnel use to provide patient care. Jeff and his team work on a computer-based diagnostic tool called CareLink. The Medtronic CareLink® Network is a web-based application and remote monitoring service that gives clinicians, doctors, and nurses online access to data transmitted from a patient's implanted heart device. The reports and data available from CareLink can be comparable to an in-office visit, and medical practitioners using CareLink rely on the data from CareLink to be accurate and available when needed—24/7.

Jeff and his small team of testers and software engineers work to make sure that's the case!

From Electrical to Virtual Circuits

Jeff started out with plans to follow in his father's footsteps as an electrical engineer. Once he realized that he enjoyed computers more than circuits, he changed his major to computer science, a field of study that capitalizes on two of his primary interests: math and computers. "Computer science is an engineering discipline that blends the mathematics and logic of engineering with the technology of computers," explains Jeff. "It's the best of both worlds." Today, with more than twenty years of experience in the field of software engineering, Jeff knows the career path he followed was the right one for him. "I do not look back on my decision to go into computers and leave electrical circuits behind. Computers and I have always understood each other."


Keeping Up to Date

Jeff knows that a big challenge he and his team face is keeping pace with the rapid growth in technology. Ongoing research and developments means that technology changes frequently, as do the languages, equipment, and approaches that make various technologies "work." Staying ahead of the curve and keeping up to date with changes and advancements in one's field is always important, but when your work involves the well-being of patients, there may be a correlation between staying "current" and ensuring the best patient care possible.

According to Jeff, he and his team monitor and evaluate their systems throughout the year, but they have to be cautious before adopting upgrades and new approaches. With a product like CareLink, Jeff and his team can't assume that newer is always better. "We are under much scrutiny to ensure our patients' safety, and as a result, we are not often the first to try out a new technology," he explains. Before adopting new approaches or making changes, Jeff has to be certain that patient safety won't be compromised.

In some areas of software testing, a "bug" is a small error that creates a problem in the application. A "bug" in a game or a word processing program, for example, might be an inconvenience or cause a user frustration—or maybe data loss. But in software engineering related to patient health care, there can't be any bugs. There is no room margin for error when a patient's heart is at stake, which is why teams like Jeff's are so important.

As a former programmer, Jeff says his understanding of computer science is an advantage in working with software verification and testing. "Having a computer science degree teaches your brain to be a better problem solver and think of issues in terms of cause and effect," says Jeff. "Finding and fixing software bugs is a very important part of what we do. If we make a mistake the patient could be impacted!"


Flexible Thinking

Day to day, Jeff needs to keep the "big picture" of his team's core application in mind even as they troubleshoot and test specific issues. Being able to employ stages of the engineering method is a critical component of his job. "As an engineer, I would say that being fluent in the practical real-world engineering method is of vital importance," says Jeff. It boils down to "being able to define and analyze a problem, specify the requirements, choose the best solution available, and implement [that solution] quickly and with strong quality."


Helping People

While careers in computer science and software engineering can mean long hours at a computer—and little time "in the field," Jeff never forgets that the product he oversees and helps maintain is one that is used to treat patients. It's a connection that makes working on CareLink and for Medtronic especially rewarding for Jeff. Jeff works in a cubicle among a hundred cubicles on the eighth floor of a modern office complex in Minnesota. He works long hours with his software developers and test engineers both in the U.S. and in Europe. He's far from the "hospital scene," but every few months, Jeff gets the chance to meet patients whose lives have been transformed by products and services offered by Medtronic. "This is the BEST part of working at Medtronic," says Jeff. "Realizing that what you do actually saves and prolongs life!"

When asked if he ever thinks about what it would be like to work on a very different kind of technology—like video games or a popular online destination like a sporting site—Jeff admits that those kinds of projects might be fun, but he questions, "If you work on your "hobby", does it remain fun as your hobby, or does it become just a job?"

For Jeff, knowing that he's helping better people's live by doing something he loves makes his career the right one for him. "It would be very difficult to get a better feeling than that from any job," says Jeff.

Categories:

 

Katie Hilpisch / Career Profile

As a biomedical engineer at Medtronic, Katie Hilpisch is making a difference in people's lives. "It is rewarding to meet someone who finds out that you work at Medtronic and wants to tell you that someone they know has a Medtronic device."

For Katie Hilpisch, a senior biomedical engineer at Medtronic, helping devise therapies for heart patients is all in a day's work!

According to Katie, biomedical engineering offers an exciting combination of research, problem-solving, and fieldwork. Biomedical engineering brings engineering, medicine, and biology together, but not all biomedical engineers do the same things or work on the same kinds of product development, research, and testing. At a large company like Medtronic, there may be many biomedical engineers working on different facets of a larger health issue. Katie and her team, for example, work in the area of "heart health," exploring medical therapies for patients with heart problems, specifically electrical stimulation (pacing) therapies. At the same time, other biomedical engineers work on different aspects of heart health, like exploring new imaging technologies that let doctors better see "inside" the body or researching the ways different substances interact in the human body.


A Collaboration Between Math and Science

Figuring out the right combinations and solutions to improve a heart patient's quality of life is a puzzle that biomedical engineers are constantly trying to solve. According to Katie, "my job is all about math and medicine!" It's a combination students might not immediately think about, but for biomedical engineers, science and math work together as keys to helping problem-solve, troubleshoot, and find solutions.

"Here's a very specific example," says Katie, "on a project I was recently working on, we were trying to reduce the flow of blood through an artery by 80%. We had to find the area of the vessel to determine an appropriate new size of the vessel to get an 80% reduction. Think geometry. Think statistics. Think measurements and calculations that you are learning right now in school!"


Between Desk and Lab

Katie splits her time at Medtronic between desk work and lab work. She estimates she spends 75 percent of her time doing computer-based research and analysis and 25 percent of her time working in research labs or in hospitals.

"Data analysis is a huge part of my job," she explains, "so using software to analyze data and calculate statistics is a big part of my repertoire. " Reading and staying up to date with both current and historical research and trials is also critical, says Katie. You have to "read anything that gives you insight into what has already been done or what other people are working on," she explains, "We don't want to re-invent the wheel."

In fact, Katie wants to take what exists and find new and better wheels. It's a process of finding the right combination and approach to improve life for patients, and that's what she enjoys most about her job. "Hands down, I most enjoy helping patients. It is very rewarding to come to work every day and get the chance to do something that helps people who are sick."


Advancing Treatment

Working at a global company like Medtronic, means that specialized groups are able to take advantage of each other's research and development when envisioning new solutions, therapies, and treatments. Katie's group isn't working on drug therapies, for example, but others at Medtronic are. Similarly, Medtronic biomedical engineers work with drug pumps, pacemakers, and other equipment that may come into play in a plan for a new heart therapy.

The process of putting new therapies into action, however, is one that takes time. New therapies go through many different types of testing, including lab-based testing using computer simulations or machines built to test possible answers. According to Katie, other stages in testing may include pre-clinical testing at Medtronic's Physiologic Research Lab, small patient studies to test for safety and effectiveness, and finally larger patient studies.

Biotechnology

Curious About Biotechnology and Medicine?
Learn more in our new Medical Biotechnology interest area!
The outcomes of large-group studies help biomedical engineers evaluate whether or not the therapy is better than not having the therapy.


Answers Take Time

On paper, the point from A to B may seem pretty clear-cut, but it can take years of testing to ensure a therapy is safe and effective. With testing of new therapies averaging 3-5 years, it is clear that accepting that testing takes time is part of the game plan for biomedical engineers. "Usually when we are planning for products, we are looking at things in a 1-2, 2-5, 5-10 and 10+ years' time frame!"


A Future in Biomedical Engineering

According to Katie, students interested in a possible career in biomedical engineering should take as much math and science as they can. But beyond schoolwork, Katie encourages students to also think outside of school. "Figure out what sets you apart," she urges. "Do something nerdy outside of school. Join a group that takes apart toasters and puts them back together. Or even volunteer at a local science museum. " For Katie, when you think about what you want to do with your life, the mantra is simple: "Always do something you love. Then it won't be 'work.'"

For Katie, heart health and biomedical engineering is where she wants to be right now. "It is rewarding to meet someone who finds out that you work at Medtronic and wants to tell you that someone they know has a Medtronic device," says Katie. "My own grandfather has a Medtronic pacemaker, so when people ask what gets me to work every day, I tell them, in the end, it's the patients."

Categories:

 

Marc Church Q&A


Photo of Marc Church.
Marc Church, Mechanical Engineer, Lockheed Martin

Earlier this spring, we profiled Marc Church, a mechanical engineer at Lockheed Martin. As a follow-up to the profile, Marc invited questions from teachers, students, and families related to his work as a mechanical engineer—and his work on spacecraft.

We are posting his answers to your questions below. Thanks so much to Marc for his generosity in sharing his time, experience, and knowledge with all of us!

If you are interested in learning more about the career of a mechanical engineer, check the Science Buddies mechanical engineer career profile.


What is the coolest project you've ever worked on?


The coolest project that I've ever worked on was, unfortunately, the result of a catastrophe. On February 1, 2003, the 7-astronaut crew of STS-107 lost their lives as the space shuttle Columbia blew up upon re-entry into Earth's atmosphere. Why did it happen? A large chunk of foam insulation broke off of the external fuel tank during liftoff.


It was a tragedy, but every dark cloud has a silver lining. I was able to help redesign the area where the foam came off. Two-and-a-half years after the accident, we returned to flight with STS-114 on July 26, 2005. Seeing the space shuttle flying again with hardware that I helped redesign was one of the proudest moments of my life.

During those two-and-a-half years, I learned more than I had in my whole career up to that point. I learned what it really took to design space hardware with all the requirements and testing necessary to make sure that our astronauts are safe. I was able to participate in some very cool testing with cryogenic (-423°F) liquid helium that represented the liquid hydrogen fuel that the external tank carries to feed the SSMEs (Space Shuttle Main Engines). I was also able to experience testing in wind tunnels, which simulate the space shuttle during launch at twice the speed of sound (mach 2).

I also learned about the hard work, dedication, and sacrifices that are a necessary part of the process. My teammates and I worked long hours and weekends, and traveled for weeks at a time, spending a lot of time away from our family and friends. However, we did it! Today, the space station is complete because of our efforts.

What could top that, you ask? I'm currently building a spaceship, Orion, to put a man on both the Moon and on Mars. I can envision a future moment when I stand outside and look up at the Moon with my daughter, Catie, and realize that there is a man on the Moon because of my efforts.


If you were to pick a science fair project to do today, what would it be?

I recently judged a science fair here in Houston, Texas and was impressed by the number of projects that were related to energy efficiency. Besides my day job doing thermal analysis of spacecraft, I also have an interest in energy-efficient buildings and reducing the amount of energy and resources we use on a daily basis.


Last year, I took a test to become a LEED-accredited professional or LEED AP. LEED stands for Leadership in Energy and Environmental Design. You'll start to see more and more buildings, schools, houses, and hospitals trying to become LEED certified. Why, you ask? Well, a LEED-certified building can reduce energy use by 25–50%, water usage by 20% or more, and reduces and recycles the construction materials needed to build it. Therefore, the building owners save money and use less of our resources, like coal and oil, which are needed to produce the electricity. LEED buildings are also brighter and healthier for occupants than non-LEED buildings, because they have highly efficient glass windows (where most of the energy enters/escapes in a building) and paints and materials like carpet with low or no VOCs (volatile organic compounds).

Thus, I would probably do a science fair project related to testing windows that would automatically darken when the sunlight shines on them, or lighten when the sunlight doesn't shine on them. This would help save money by reducing the amount of heat allowed into a building. I would also consider a science project related to capturing rain water from the roof of a house in such a way that it could be used to flush toilets or water the yard. Water is expensive these days!


How much air do you need to carry to go to space?

There is no air in space because it is a vacuum. In order for astronauts to live in a spacecraft, they need an environment similar to Earth! They must have air to breathe, food to eat, water to drink, and a comfortable temperature.


Earth's atmosphere is a mixture of gases (78% nitrogen, 21% oxygen, 1% other gases) at a pressure of 14 pounds per square inch (psi). (If Earth were not pressurized, the vacuum in space would crush it like a soda can. The spacecraft must provide a similar atmosphere. To do this, liquid oxygen and liquid nitrogen are carried on board in two systems of pressurized tanks. The cabin pressurization system combines the gases in the correct mixture at normal atmospheric pressure.

Besides air, water is the most important element aboard a spacecraft. In the space shuttle, water is made from liquid oxygen and hydrogen in the fuel cells. The fuel cells can make 25 pounds of water per hour. The water from the fuel cells passes through a hydrogen separator to eliminate any trapped hydrogen gas. Excess hydrogen gas is dumped overboard. The water is then stored in four water storage tanks, located in the lower deck. Drinkable water is then filtered to remove microbes and can be warmed or chilled through various heat exchangers, depending upon the use (food preparation, consumption, or personal hygiene). Excess water produced by the fuel cells gets routed to a wastewater tank and subsequently, dumped overboard. So, how much? In terms of the space shuttle, it uses 7.7 pounds of nitrogen and 9 pounds of oxygen per day to provide breathable air and to pressurize the crew cabin. Assuming the longest space shuttle mission (17 days) means the following:

7.7 pounds/day x 17 days = 131 pounds of nitrogen


and

9 pounds/day x 17 days = 153 pounds of oxygen

Total = 284 pounds of breathable air



How do you test the production models? And what kind of temperatures do they have to tolerate as part of Orion?

Testing and verifying that you meet the requirements given to you by your customer (NASA) are an essential part of spacecraft design and development.


For Orion, we have a variety of tests to meet the requirements. Let's start at the bottom (component level) and work our way up (spacecraft level).

Each component on the spacecraft is tested to ensure that it passes the environments it expects to see during a mission. The two predominant environments are vibrations (shaking of component due to vehicle acceleration) and thermal (temperature ranges). The component will undergo "shake and bake" testing under environments, based on the analysis and simulation predictions—which is what I do for a living. The environments are based on where the component is located on the spacecraft and to what it is attached, all based on the laws of physics. We add margin for error (making things worse) to account for any errors and unknowns in our analyses to ensure the components will work in space.

The spacecraft level is where all the components are assembled and you have your full spacecraft built. The spacecraft is put through a series of system-level "shake and bake" tests. For the "shake" test, a large shaker table is built to simulate predicted environments. For the "bake" test, we use a thermal vacuum chamber. We put the spacecraft in a vacuum to simulate space and chill the walls of the chamber to simulate the extreme cold environment of space (-454 degrees Fahrenheit). We then use heat lamps located around the spacecraft to produce heat to generate the hot space environments (due mainly to the Sun's energy and reflected energy off of the planet). The spacecraft is then powered on to make sure all the components and systems on the spacecraft work as designed. These tests are done to qualify the spacecraft.

After ground tests, we launch the real thing! For Orion, we will launch an unmanned spacecraft to approach the ISS (International Space Station) in 2013. We will then follow that up with a manned mission (2 astronauts) in late 2013 or early 2014!

Recently, Orion performed a major test for our Launch Abort System, which is used to move astronauts away from the rocket during the launch in the event of an emergency. It was a great success for our team, as they took all the components and integrated them into a system that performed perfectly. To quote our chief engineer, "it was like a stroll in the park!" A lot of hard work and dedication went into this test. You can view the test video here: www.nasa.gov/mission_pages/constellation/orion/index.html.


What are the best and worst parts of your job?

The best part of my job is working with cutting-edge technology and watching this technology get designed, built, and integrated to become a complex system that is used in space or here on Earth. I also get to work with some of the smartest people who are real-life rocket scientists. After the space shuttle Columbia exploded in 2003, I worked very hard with a team of people to fix the problems and get our space program back on its feet. I'll be honest, that was the hardest and most-complex work that I have ever had to do in my job. However, I had an incredible sense of pride and enthusiasm when the space shuttle launched again two and a half years later. It made all the hard work and "worst" parts of my job worth it!


As for the worst parts...in my current job, I spend a lot of time in front of a computer, which gets tiring at times. I also work in a cubicle, which is a partitioned office with no real walls, which can be distracting and loud at times. One day I hope to have my own office. I have a lot of meetings that I have to attend—it is hard to get work done when it seems you are always in meetings!



I'd like to learn about the toughest job you've worked on. What problems did you encounter, and how did you get through it? Do you have any tips on how to approach an engineering problem?

I've mentioned in some of the above postings about my work on the space shuttle external fuel tank after a piece of foam insulation broke off an area on the tank, punched a hole in the shuttle Columbia's wing, and eventually lead to its demise and the death of the seven astronaut crew on February 1, 2003.

The work that followed that incident was some of the toughest work that I have ever done. A few months before the accident, I changed departments from structural design to thermal analysis. I was assigned a thermal model, called the Bipod, with which I was supposed to get familiar. Well, I got very familiar with it, as this was the location where the foam insulation came off the tank and hit the shuttle. It was my job to redesign this area to remove all of the foam off of the top of the Bipod so that it would never be able to repeat what it did to Columbia on a future mission.

This model was an old model, dating back to the 1980s. It only existed as lines of code, like a computer program, no pretty pictures or high-tech software. I was on the hook to figure out how the model could be redesigned to make it safe for return to flight for the space shuttle. No sweat, right?

To make the design work we had to remove the foam insulation off of the top of the bipod fitting. The foam was there to begin with because the fuel in the external fuel tank is cryogenic; liquid hydrogen at -454 Fahrenheit....brrrrrr. If the foam wasn't there, ice (a lot denser than foam) would form on the bipod fitting and could break off during liftoff and hit the shuttle. We had to make a "hot plate" out of copper and put four heaters inside of it. We would then put the bipod on top of it such that the heat would transfer into it and keep it warm and ice-free. Sounds simple...right?
Well, it's always the unknowns that bite you. In this case, we learned a lot through testing a scale model of the bipod that we built from real parts. It turns out that the temperature sensors that we used to control the temperature of the hot plate were giving us fits. The wiring for the sensor was glued to the tank, which I mentioned was at cryogenic temperatures. Well, we found out that the temperature sensor wire was sucking all of the heat out of the sensors. So instead of telling us that the bipod was at a toasty 37 degrees Fahrenheit (above freezing) it was giving us a reading of -45 degrees Fahrenheit. This was late in the design process and it seemed like this was going to jeopardize our design. Ugh! What were we going to do?

The team worked together and came up with a solution that involved thermally anchoring the wire inside the copper plate. Without getting into too much detail, the wire coming out of the temperature sensor was kept warm for a long enough distance as to not suck out as much heat. We still had some error, but we understood that when it read say 10°F that it really meant 37°F. That's the way we fly it today!

My tips for approaching a problem....what are your knowns and unknowns? Draw a picture or a diagram and label it with the information you were given. Look for clues that can make the problem easier. In my world, these clues exist as assumptions and boundary conditions.
For example: A physics question might ask, "If you throw a ball in the air at a given speed of 20 miles per hour, what is the speed of the ball at its max height?" Well, I know that, according to physics and the laws of gravity, what goes up must come down. If I throw the ball up at a given speed, I know that gravity is going to slow it down until the ball reaches its maximum height, and then the ball will come down. At its maximum height, the speed of the ball is ZERO! From physics, I can use equations to figure out how high the ball went. Or if the ball was thrown at an angle, I can figure out how far the ball traveled horizontally.

My biggest tip to tackling an engineering problem is this: If you're not sure, ASK! There's no use pounding your head on your desk when a simple question to a teacher could turn on that lightbulb for you!


It sounds like the systems you are working on have to survive extremes of hot and cold. What kinds of things can you do as an engineer to protect the devices from damage?

I do have to protect the spacecraft, rocket, etc. from the extreme hot and cold. Let's start with the hot side.


During liftoff, as a rocket is racing to space, the air around the rocket creates friction, which, in turn, gives off heat. Therefore, we have to use materials called ablators that are placed on top of the metal (mostly aluminum) rocket to protect it.

An ablator is a material made up of cork, a binder or glue, and tiny silica (glass) spheres. The ablator erodes slowly, which allows it to dissipate the high heat due to air friction, while the remaining material keeps the rocket structure cool. You'll also find ablators on aeroshells, which are used when spacecraft enter the atmosphere of Earth or Mars.

A spacecraft in orbit around Earth might have a lot of electrical components that generate a lot of heat. Removing this heat so that the components do not exceed their operating temperature can be a challenge. One way to do this is to create a radiator. The radiator has a view to deep space, which is -454 degrees Fahrenheit. Through radiation heat transfer, the radiator can dump the heat generated by the electronics and keep them cool.

On the cold side, we use a couple of different methods. We can passively control the temperature by using control coatings and/or multilayer insulation blankets (MLI). Since the majority of heat lost in space is due to radiation (heat transfer through electromagnetic waves), the emissivity of a surface is important. The emissivity is the measure of a material's ability to reflect heat. In an MLI blanket, many layers of a thin film of Kapton are sewn together to make a blanket that minimizes heat loss. You'll easily spot MLI on spacecraft; it will be a shiny aluminum or in some cases, a gold-plated surface.

We can also actively control the temperature through the use of heaters. The heaters are attached on the component that needs to be warmed up. In order to use heaters, you need electrical power, which can be generated through the use of batteries stored on the spacecraft, or by harnessing the energy from the Sun, using solar arrays. Check out the massive solar arrays on the international space station!

Most spacecraft use both passive and active temperature control.


How do fins on a rocket affect its flight?

The fins on a rocket provide stability for the rocket during flight. During flight, the rocket could experience small gusts of wind or thrust instabilities that can cause it to wobble. The fins produce lift forces that "steer" the rocket back onto its flight path so that it remains stable. Larger, full-scale rockets do not rely on aerodynamics to steer them and do not have fins. They use gimbals, which allow the rocket engine nozzle to move and guide them during liftoff.


As an engineer, do you have to do a lot of math everyday?

I would say that I don't do a lot of physical math (adding, subtracting, multiplying, dividing, etc.) on a daily basis. I let computer programs like Microsoft Excel to do my dirty work! However, I deal with math all day when I'm building models for example. I use geometry to draw the models I need to represent the spacecraft. I also use a lot of things that I've learned in math classes to analyze data and read graphs. For example, I had to look up a value off a chart that had logarithmic scales. Had I not learned what the LOG scale was in math, I would have been unable to read the graph!


Math and science are essential to being an engineer. I know many people shy away from engineering because of math and science. Like anything else in life, though, a little hard work now will pay off tenfold later. Focus on the theories behind the math and science and it will make all the word problems and homework easier and less frustrating.


Do you think getting a master's degree after earning a bachelor's degree in mechanical engineering would be beneficial? Or would a master's lead to a job in a different (maybe more-specific, somehow) area of science?

I think that getting a master's degree after a bachelor's degree is very beneficial. I think it depends on what works for you. Some of my colleagues stayed in school after getting their bachelor's degrees before entering into a career. Others, like myself, waited until after starting a job. Most companies that hire for this line of work will pay for all or most of your master's degree, as long as you make a grade of B or above. Then, they'll give you a pay raise for getting your master's!


My best advice is to take getting a Masters degree seriously regardless of whether you do it right after your bachelor's degree or after you've started working for a company. I have yet to complete my Masters degree; it's something I hope to finish in the next few years. I was on the right path towards a degree but was derailed due to my workload at my job at the time. I didn't think I could devote the time to both school and my job. Looking back, it was probably just an excuse and I should have pressed on to finish my degree. Get it done early so that your career and outside distractions don't deter you!

Categories:

 

Photo of Marc Church.
Marc Church, Mechanical Engineer, Lockheed Martin

Marc Church, Senior Mechanical Engineer at Lockheed Martin, has always been a "builder" at heart. At age nine, he dreamed of being an architect and drew house plans for fun. A few years later, a retired railroad engineer moved in next door, and Marc's focus switched from architecture to engineering as he perused plans of railroad bridges and received mentoring from his neighbor.

Marc went on to study mechanical engineering at Louisiana State University. Then during the summer of his junior year, he interned with Lockheed Martin. As an intern, he worked on several projects, including the Space Shuttle External Fuel Tank and X-33, an early prototype of single-stage-to-orbit reusable launch vehicles (SSTO RLVs). At the end of the summer, Marc transferred to the University of New Orleans so that he could work part-time at Lockheed Martin.


A Career in Mechanical Engineering: Not too Hot; Not too Cold

Today, Marc has been working in the field for 11 years. Day to day, he works on thermal analysis of spacecraft components. "I have to make sure that parts of the spacecraft don't get too hot or too cold and that they fully function and do what they are supposed to do," explains Marc.

This kind of testing and analysis involves using computer design programs to build digital thermal analysis models of actual components. These models are then tested under a variety of simulated conditions. For example, a component that might be on the outside of a system could be affected by air friction during liftoff of the rocket into space, which would cause it to heat up. Alternately, spacecraft components also have to perform reliably in the extreme cold of space during orbit.

Strategically thinking through issues that might arise, Marc designs and runs his tests. "It's kind of like playing with Lego blocks," says Marc. "I'll build different components and integrate the parts into a model representation of the spacecraft. Then, I'll run through simulations with the spacecraft in different orientations."

Currently, Marc is working on Orion, a vehicle he describes as "the eventual replacement to the space shuttle that will take us back to the Moon and Mars and wherever else we want to go." Testing a new spacecraft can involve hundreds of simulations. According to Marc, it took 700 simulations just to be sure Orion won't get too hot or too cold when put into orbit. Design plans for the Orion met NASA requirements in August 2009, so Marc and his team are working on refinements to reduce the weight and increase the performance of the spacecraft, thus reducing the cost associated with the Orion's eventual flight and launch.

Once this wave of design optimizations is in place, the team will begin building and testing physical components (versus simulations and models) and Marc's job will shift from desk-based computer analysis to hands-on design and testing of production models.


Always Something New

For Marc, working at Lockheed Martin as a mechanical engineer requires a balance of math, physics, and structural engineering. It's a combination Marc enjoys. "I like designing something new and being creative," he says. "I like the challenge of the cutting-edge technology I'm working on."

Marc is also proud that his work for Lockheed Martin is on "projects that are for the betterment of the United States. It's American-made for the American people."

Marc didn't grow up to design houses as he'd imagined as a boy, but he stayed pretty close to his early ambitions. At age nine, when he did a science fair project titled "Why Do Tall Buildings Sway in the Wind?," he was simulating the impact of high-level winds and looking to see what changes in design would allow a building to "bend" rather than "break."

Little did he know then that he would grow up to perform similar testing and creative analysis in the design and development of spacecraft!


Ask Marc a Question

Questions about engineering? Questions about thermal testing? Curious about spacecraft of tomorrow?

Do you have questions for Marc? Marc has agreed to answer questions from students, teachers, and parents related to his career, including his work for Lockheed Martin, the space-related projects on which he has worked, and thermal testing.

Update: March answered all of the questions submitted. You can find his answers here.

Year in Space calendar photoWe'll pass along a selection of questions to Marc and post his answers here on the blog! This is a great opportunity for students to get an inside look at the world of mechanical engineering.

On April 12, we'll do a random drawing from everyone that submits a question and send out six 2010 The Year In Space calendars, courtesy of The Year in Space, to winning participants. Note: US only.



Categories:

 
Science Buddies Science Activities

Science Buddies Summer Science Roundup




Trending Posts

Family Science

Help With Your Science Project

Your Science!
What will you explore for your science project this year? What is your favorite classroom science activity? Email us a short (one to three sentences) summary of your science project or teaching tip. You might end up featured in an upcoming Science Buddies newsletter!


Archives




You may print and distribute up to 200 copies of this document annually, at no charge, for personal and classroom educational use. When printing this document, you may NOT modify it in any way. For any other use, please contact Science Buddies.