Category Archives: Research

Spacecraft Research is at it again

It’s been a little while since I checked in with the goings-on back at my Cornell research lab. Totally unsurprisingly, some very cool things are happening there!

One is that the Sprite and KickSat project has gone all the way from a back-of-the-envelope concept when I was at the lab to a flight manifest! Sprites are tiny spacecraft – think the size of a coin – that consist of little more than a solar cell, a little CPU, and a diminutive radio. They are pathfinders for an idea that, rather than relying on a single monolithic (and super-expensive) spacecraft, instead we could just run off a batch of a million tiny satellites and fling them all out into space to cooperatively complete a mission. Some of the applications we talked about included integrating basic lab-on-chip functionality to test for biomarkers, and then rain a bunch of the Sprites down onto Mars or Europa. They wouldn’t return the same wealth of data of a NASA flagship mission, but they would tell us where the interesting things are. Another reason why tiny spacecraft are cool is because they interact differently with Solar System objects than large vehicles do – so they might be able to take advantage of light, magnetism, or planetary atmospheres in different ways.

The KickSat project was the brainchild of grad student Zac Manchester. It’s a simple CubeSat design with a spring-loaded deployer, designed to release a couple hundred Sprites. On the ground, Zac can then track the intermittent radio signals from all these mini-spacecraft, and evaluate how well their unshielded components survive in space. Radiation will eventually kill them, but with many copies of the same spacecraft, we’d expect to see them die out statistically. They’re spacecraft with a half-life, and as long as the half-life is long enough to complete the mission, we don’t care that a huge number of Sprites burned out.

When I left the lab, Zac was applying for grants to build the KickSat hardware. But – despite the cool concept – there weren’t any takers. Eventually, he decided to turn to KickStarter to see if he could crowd-fund some spacecraft research. He ended up raising almost three and a half times as much money as he asked for, and become something of a pioneer for crowdfunded space activities! Zac is now working at Ames Research Center to perfect the Sprite and KickSat designs. They will be launching on the same SpaceX Falcon 9 rocket that will carry supplies to the International Space Station in September. This is actually the first CubeSat from my lab to make it all the way to launch, so I say: Go Zac!

Second, a project that is perhaps a little less flashy but a little closer to my heart has been making some great strides. Ben Reinhardt has been squirreled away in the same basement lab I remember, working on what he calls “eddy-current actuators.” The more fanciful – and very nearly accurate – name for the devices he is working on would be “tractor beams.” He wants to use these to grab onto defunct satellites, the outside of the Space Station, or maybe even some asteroids and comets, all without mechanical contact.

I was still active in the lab when this project got off the ground. In fact, I put together one of our first tabletop demonstrations of the principles involved: a changing magnetic field generates eddy currents in conductive materials; these currents have their own magnetic fields which we can push or pull with magnets. That’s where I left the project, though…a quick video where I waved a magnet around, some rough number-crunching to show that the induced forces were feasible for applications, and then I was out to let other members of the lab hash out the details. (That’s the fifth-year grad student for you!)

The cool news is that Ben has gone from my rough video to a much more carefully controlled demonstration. He’s generated attractive and repulsive forces in a bare piece of aluminum (not unlike the skin of a spacecraft), without touching it, and he’s working on characterizing the design space of his device. This is a critical step in figuring out how to go from proof of concept to a useful technology, and it’s a step I remember quite well. While Ben’s twitching pendulum might not look to you like the tractor beams from Star Trek, it is a clear and measurable experiment illustrating the device. I went from similar experiments in my first two-ish years of grad school to flight demonstrations in my third and fourth; I hope Ben follows a similar trajectory. And who knows – if some companies or space agencies take an interest, we may soon see spacecraft grappling asteroids and assembling components with eddy-current tugs!

Ben and some of the other Cornell Space System Design Studio grad students are keeping a blog about their technology research projects, which you can read here. I think it’s very cool to see what’s going on in the lab!

CubeSats are Cool Sats

This past week, some CubeSat developers got to see something that few space programs – and almost no CubeSat programs – ever do.

Floating by…

These CubeSats are “1U” size – 10 x 10 x 10 cm cubes – and deployed from a device mounted to the International Space Station. This deployment mechanism afforded Expedition 33 astronauts the ability to photograph the tiny spacecraft as they serenely drifted past the Station’s solar wings. Not many spacecraft builders ever get to see their work take flight!

A common scene in CubeSat concept art
A common scene in CubeSat concept art

CubeSats are awesome because they cost less than $100,000 to build and launch, which means that they can be playgrounds for new technologies. In an economic environment where it takes $30 or 60 or 80 million to put a satellite to orbit, and where businesses’ most intense priority is on increasing next-quarter earnings, very few private organizations are willing to gamble on new technologies or designs – even if those designs might improve the state of the art and give a company a huge advantage. But CubeSats are cheap. They fall within university research group budgets. They let technology developers take risks. They can be pathfinders for new ideas!

Calling All Space Tech!

In grad school, I became a big fan of NIAC (the NASA Institute for Advanced Concepts) and the Office of the Chief Technologist. These wings of the NASA organization support research into far-flung, visionary technological concepts. They are the parts of NASA pushing for the kinds of research that will usher in the next generation of space exploration.

The new NIAC call for proposals is out. Interestingly, this time it includes a specific call for “citizen science.” So, if you’ve got some crazy ideas for spacecraft technology…why not try for it?

Kick Yourself into Orbit!

Ah, I’ve only been out a few months, but I already miss some things about being in grad school! For instance, I miss all the crazy brainstorming of new and wild space systems, missions, and technologies. No doubt you, dear reader, also miss my crazy brainstorming: after all, that is how I ended up writing blogs about space battles or missions to Europa or what the Earth would look like with rings or the science of Avatar. Now I have an industry job where people tend to care more about “affordability” and “reliability” and “performance,” than they do about harebrained schemes to drop space probes into the Europan ocean.

But, fear not, intrepid reader who has been sticking it out hoping for another crazy notion to appear here! You see, my research group at Cornell is still working at churning out wild ideas. And you can participate!

Check out this message from Zac, who was starting his Ph.D. as I was on my way out:

Zac has set up a page on KickStarter, which you can jump to by visiting The idea behind KickSat is to make a bare-bones 10x10x10 cm CubeSat which contains hundreds or thousands of microchip-sized satellites called Sprites and will deploy them all in low Earth orbit. The KickStarter platform means that, if you want, you can sponsor your very own Sprite – Zac has even defined a sponsorship level at which you get to write your own flight code for the tiny spacecraft to run in orbit!

The spacecraft, which each could fit comfortably in the palm of your hand, are very simplistic as far as spacecraft go – they consist of solar cells to charge a little bank of capacitors, a teeny TI processor for a brain, and a little antenna. These are proof-of-concept spacecraft, and are actually derived from three test units which my lab group sent up to the Space Station on the last launch of the Space Shuttle Endeavour! In the future, they hope to integrate other sensors onto the chips to give Sprites more capabilities. One of the ideas batted around during lab meetings that I consider a personal favorite: put “lab-on-chip” detectors on a Sprite to look for characteristic organic compounds (like nucleic acids!) and program them to simply send a chirp back if they get a positive result. Send a million Sprites to Mars, and listen to the peeps – and then you know where on the Red Planet the next big flagship mission has just got to go!

Imagine if you got the shot at writing the flight code. If you could put a solar cell in space and make it beep, what could you measure? How creative can you get in getting the Sprite’s whisper of a radio signal to carry information? Could you receive enough data to tell how fast the chip is spinning and seeing the Sun, or how much average power it has to work with, or how long it lasts before an errant proton from the solar wind blasts your Sprite out of the sky? The chance to put your own code on a spacecraft, even such a simplistic one, offers a lot of learning opportunities.

(Incidentally: one question that Zac and his research advisor, Dr. Mason Peck, get a lot is some variation on: “Hey, paint flecs moving at orbital velocity are enough to crash through the Space Shuttle windows. Aren’t these Sprites going to become dangerous space junk?” The answer is that yes, the Sprites could be hazardous as long as they are in orbit; but the orbit that KickSat will reach is going to be within just enough of the Earth’s atmosphere that all the Sprites will get dragged down in a couple days. The special property Sprites have that influences this fast orbital decay – and other effects – is a high surface-area-to-mass ratio.)

KickSat has already reached its minimum fundraising goal to start building hardware. However, the project is still looking for more backers to secure a commercial launch opportunity, which will offer more certainty than applying for a free launch program through NASA. But if Zac gets to about $300,000 of funding, he thinks that will be enough to start looking at new technologies to shrink the Sprite chips down to even smaller sizes – and offer even more capability in the future!

Cool stuff. I’m glad to see the Cornell Space Systems Design Studio keeping the wild space ideas flowing!

Bright and Dark

I read an article today that simultaneously made me very happy and very depressed. The article is this: “Iacocca picks a likely winner — for diabetes patients,” from the Boston Globe. It’s about how a former Chrysler executive is bankrolling research that has reversed type 1 diabetes in a first-phase human trial. An auto industry exec is involved because

when MGH [Mass General Hospital] went to the pharmaceutical industry looking for funding to research a pancreas-regenerating drug, “everyone said, ‘You’re reversing the disease. How are we going to make money?’ ’’

I am really excited, because Dr. Denise Faustman’s research team is planning the next phase of human trials, which means that in three years’ time there could be an established cure for type 1 diabetes. Just in time, too: I’m so skinny I’ve been having a hard time finding places to put my insulin pump’s infusion sets! And the curing agent is a vaccine that we’ve known about for 80 years, so there’s no question as to its safety – only its effectiveness – and it should be readily available!

(When I first heard about this research, I was a senior in high school and I immediately thought of the scene in Star Trek IV: The Voyage Home where Doctor McCoy completely restores a woman’s kidney function by having her pop a single pill. “What is this, the dark ages?” he proclaimed.)

But reading, in print, the attitude of the pharmaceutical industry puts a huge damper on that feeling. These corporations don’t want to cure my disease, because a cure would dry up one of their tens of thousands of reliable revenue streams and they would make slightly smaller profits. Hey, pharmaceutical companies, just in case you were wondering: you’re assholes.

This situation seems, to me, to be a clear-cut case of how unchecked corporations can act against a society’s best interests. As an experimentalist, I feel comfortable stating that capitalism, in general, is an economic system that is very successful at distributing resources and maintaining high standards of living. However, we have here a situation where an industry would rather spend its time and resources treating a potentially curable disease. This course of action wastes time, effort, and money, and causes pain and suffering of many individuals. Now, if you are both sufficiently pro-business and sufficiently heartless, you might argue that the treatment of diabetes is an industry that sustains a good number of companies and jobs – and that it is at least possible that the better course of action for American society is for me to keep on suffering so that those jobs and industries are maintained. It strikes me that we might as well get together a fund to pay those people to bang rocks together. My point in erecting that straw man is this: if pharmaceutical companies cure this one disease, then all the people working on treating that disease can push their efforts toward something more worthwhile. It’s not like the world has any shortage of disease.

I believe that situations like this are where government can play a major positive role. It’s not in a corporation or industry’s best interest to do something that would be in society’s or individuals’ best interests, and so an agency like the NIH could step in and provide funding for higher-risk, higher-reward research like Dr. Faustman’s. (Well, actually, in her case it seems like it’s just high-reward.) This is the reason why we have the NSF. It’s the reason why we have national laboratories. It’s why we have the NIF. It’s why we have NASA. So that, as a society, we can progress.

There’s another excellent reason for government to be a player in this area, too. Medicine is an arena populated by corporations and helpless victims. I can’t exactly vote with my feet and take my business elsewhere to get a cure for diabetes – I need insulin or a cure or I die. I don’t have any bargaining power over these companies. Similarly, people who go into emergency rooms aren’t scanning a McDonald’s-style menu of medical procedures, evaluating costs with what they would like to have – they are watching doctors and nurses bustle around them telling them what is about to happen next, and rooting for those doctors and nurses. Then, when it’s all over, the corporations step in to tell patients how much money they owe. There needs to be another force here, once that works for patients.

By the way, you can donate directly to Dr. Faustman’s lab at this link.

The Television Episode Experience

I finally got a chance to watch the episode of the National Geographic Channel’s “Known Universe” that filmed partly in my Cornell research lab. The episode is about how we currently build stuff in space, and how we might build more advanced or complicated structures in the future. Naturally, my flux pinning research fits into the “future” part of the show. And, at my research adviser’s suggestion, I was the guy on camera with the host. (Probably due to my propensity for putting research stuff on YouTube!)

This whole thing was a really interesting and fun experience for me. It all started with some idle speculation on space battles, which turned into one of Gizmodo’s hottest articles in December ’09, which ended up with a Nat Geo producer calling me on the phone. To my immense grad-student pleasure, he asked me what my research was about. And ta-da, our lab got featured on one of their shows!

Kids: let this be a lesson to you about what happens when you have thoughts and put them on the Internet in a blog!

We spent the better part of a month preparing equipment in our lab for the TV shoot, and an entire working day doing the actual filming, all for a five-minute segment in the episode. I have to say, I’m impressed with how well our topic got covered in such a short time, given how long I usually spend explaining it and how much material we spent filming! There’s a lot to be said for having professional editors who want to tell your story. If you caught the episode last Thursday (it will re-run soon; I believe tomorrow at 3 PM is one slot), you saw me show the host, Johns Hopkins physicist David Kaplan, three features of magnetic flux pinning that we feel could make it the basis for a future in-space construction technology:

"Known Universe" host David Kaplan pokes at one of our levitating magnets in the lab. (Photo Credit: ©NGC)
  1. Pinned magnets and superconductors can attract one another and stick together without physically touching. David best demonstrated this when he held a superconductor in one hand and a magnet in the other, and the magnet jumped across a distance of a foot or two to lock back onto the superconductor.
  2. This effect does not necessarily require any power or control inputs. I explained at one point during filming that, although we have to supply liquid nitrogen or power a cryocooler in order to get flux pinning to work on Earth, a spacecraft might only need to shield its superconducting elements from sunlight. (That detail didn’t make it into the final segment.)
  3. Flux pinning can not only lock structures into place, but it can also form the basis for reconfigurable multiple-module space structures that change their shape in response to changing mission goals. Our research group likes to think about morphing space telescopes, planetary orbiters, or solar power satellites, but there’s no reason why human-habitable space stations are out of the question! (If you provide flexible tubes for inhabitants to get from module to module, of course.)

Continue reading The Television Episode Experience


Next Thursday, 9 June, an episode of “Known Universe” will air on the National Geographic Channel entitled “Construction Zone,” about the ways humans build things in space – or might build them in the future. For a couple-minute segment about future space construction technologies, the host and crew came to my Cornell research lab and filmed a bit with me about my flux-pinning technology research!

I’m excited and nervous – excited, because this is my first real TV appearance, it’s all about the cool possibilities that could come from my graduate research, and I want to see how it comes out – but nervous, because as a researcher, I know what kind of story I want to tell about my subject, and I don’t know if it will come out the same way after editing. I know what footage we shot, but I haven’t seen the finished product yet!

For now, I can say this: I had a blast filming. Explaining the concepts to the host and doing demonstrations with him was a lot of fun. I think there was plenty of footage that made my research come across well.

The only downside is that I don’t have cable in my new apartment!

I Guess That’s It

I have successfully defended my dissertation. I would appreciate it if you would address me by my correct title, now: Doctor of Rocket Science.

(I’m kidding.)

The funniest thing about this to me is that I know that the research I’ve been working on isn’t done. There are more investigations to pursue, more refinements to write into the code, more variations to try in simulation, and more experimental verification to perform. Research never stops. But at some point, we grad students have to decide, with our advisers, when we have made a sufficient contribution and should wrap up our work into a complete dissertation. Still, it doesn’t quite feel like I’m “done,” because I know that the research has much further to go! It’s kind of anticlimactic.

A rather nice capstone, though, was spending last week getting the lab ready for, and filming, a bit for the National Geographic show “Known Universe!”

How to Build a Tractor Beam

Hello, Intertubes! I have been slacking off on the blog in favor of preparing my dissertation and the presentation for my defense. I know, excuses, excuses…

To keep all eighteen of my intrepid readers happy, here is a video that recently went up on my lab group’s YouTube channel:

That’s me demonstrating the physical principles that could be used to make a real-life tractor beam that can push, pull, and manipulate spacecraft. The device would work by pumping changing magnetic fields at a target spacecraft, exciting eddy currents in the spacecraft’s aluminum skin. These currents interact with the magnetic field from the tractor beam device, allowing it to push, pull, or rotate the target.

In the video, I generate these changing magnetic fields by moving a big rare-earth magnet around. On a spacecraft, a more likely tractor beam device would be a set of electromagnet coils. I calculated that, with reasonable power requirements, such a device could exert ion-engine-scale forces on a target several meters away. More powerful electromagnets would increase that range.

Inventing New Uses for Dropbox

After buying my third computer (I have a work desktop in my office, a personal laptop, and a personal tablet), I became a big fan of Dropbox. The service is a paradigm of cloud computing: I get a folder on all my computers that acts like a normal Windows folder, but syncs up with a remote server every time a file changes. I immediately started using the service for, say, my dissertation-related files – which are now accessible from all three computers. As a plus, Dropbox downloads and keeps a local copy of all files in the folder, so my dissertation exists in four identical copies (all my computers plus the Dropbox server – which gets backed up on its own!) so I don’t ever have to worry about that work disappearing into some black hole if my hard drive crashes. And since I got a Droid Incredible, I can even access files in my Dropbox from there. Yippee!

I just came up with a devious new use of the software to add to all that. I do a lot of Matlab simulations these days, and they run fastest on my work desktop. However, these simulations take a long time, so I’d like to be able to set them up and get their results in short, intermittent checks while I’m traveling for the holidays. (Hey, I’m trying to move my research along efficiently and finish up my degree! Really!) But I haven’t been able to get Windows Remote Desktop to work – it seems that my department at Cornell keeps those ports closed and I haven’t been able to find a way around it.

So here’s what I did: I wrote a Matlab script that checks for the presence of other Matlab scripts in an input folder in my Dropbox. It then runs any scripts it finds, captures their output, and deposits that into another folder in my Dropbox. (I encapsulated the run command inside a try/catch block which also plops any errors into the output folder.) The script then deletes the file from the input folder and loops. If I put a file named “stop” in the input folder, the script cuts itself off. I think next I will add some code looking for a file named “clean” and responding to that by clearing all variables except those used in the wrapper loop.

From any of my computers, I can now write a Matlab script to do some simulations and copy it into the “input” folder. When my work desktop syncs up with Dropbox, the Matlab loop catches the script and runs it. I can check the Dropbox output folder later, again on any of my computers, to see what happened!

Maybe this little trick will be useful to someone else out there, so I decided to share it. Happy Hanukkah, grad students of the world!