I’ve been soldering for a long time, and I take pride in my abilities. I won’t say that I’m the best solder-slinger around, but I’m pretty good at this essential shop skill — at least for through-hole and “traditional” soldering; I haven’t had much practice at SMD stuff yet. I’m confident that I could make a good, strong, stable joint that’s both electrically and mechanically sound in just about any kind of wire or conductor.
But like some many of us, I learned soldering as a practical skill; put solder and iron together, observe results, repeat the stuff that works and avoid the stuff that doesn’t. Seems like adding a little inside information might help me improve my skills, so I set about learning what’s going on mechanically and chemically inside a solder joint.
Continue reading “What the Flux: How Does Solder Work Anyway?”
One of the essential problems of bio-robotics is actuators. The rotors, bearings, and electrical elements of the stepper motors and other electromechanical drives we generally turn to for robotics projects are not really happy in living systems. But building actuators the way nature does it — from muscle tissue — opens up a host of applications. That’s where this complete how-to guide on building and controlling muscle-powered machines comes in.
Coming out of the [Rashid Bashir] lab at the University of Illinois at Urbana-Campaign, the underlying principles are simple, which of course is the key to their power. The technique involves growing rings of muscle tissue in culture using 3D-printed hydrogel as forms. The grown muscle rings are fitted on another 3D-printed structure, this one a skeleton with stiff legs on a flexible backbone. Stretched over the legs like rubber bands, the muscle rings can be made to contract and move the little bots around.
Previous incarnations of this technique relied on cultured rat heart muscle cells, which contract rhythmically of their own accord. That yielded motion but lacked control, so for this go-around, [Bashir] et al used skeletal muscle cells genetically engineered to contract when exposed to light. Illuminating different parts of the muscle ring lets the researchers move the bio-bots anywhere they want. They can also use electric stimulation to control the bio-bots.
The method isn’t quite at the point where home lab biohackers will start churning out armies of bio-bots. But the paper is remarkably detailed in methods and materials, from the CAD files for 3D-printing the forms and bio-bot skeletons to a complete troubleshooting guide. It’s all there, and it could be a game changer for developing the robotic surgeons of the future.
Continue reading “Genetically Engineered Muscle Cells Power Tiny Bio-Robots”
I had a friend who was an engineer for a small TV station. I visited him at work once, and despite the fact that he wouldn’t let me climb the 1,200′ antenna tower, I had a great time. I was working for a video production studio at the time, so there was a fair amount in common about our jobs. One of the regular chores we faced was cleaning the heads on tape machines. He had a 5-gallon pail of cleaning solution under his bench that he told me was Freon, which he swore by for head cleaning and general contact cleaning. He gave me some for my shop in a little jar.
I never knew for sure if that stuff was Freon, but it was the mid-80s, shortly before CFCs were banned, so it might have been. All I know is that I’ve never found its equal for cleaning electronics gear. With that in mind, I thought I’d look at contact cleaners that are in use today, what’s really going on when you clean contacts, and why contacts even need cleaning in the first place.
Continue reading “Down and Dirty with Contact Cleaners”
You say you need some graphene so you can invent the Next Big Thing, but you can’t be bothered with processes that yield a few measly milligrams of the precious stuff. Luckily for you there’s a new method for producing gram quantities of graphene. Perhaps unluckily, it requires building a controlled fuel-air bomb.
Graphene is all the rage today, promising to revolutionize everything from batteries to supercapacitors to semiconductors. A molecularly-2D surface with unique properties, graphene can be made in very small quantities with such tedious methods as pulling flakes of the stuff off graphite lumps with Scotch tape. Slightly less ad hoc methods involve lasers, microwaves, or high temperatures and nasty chemicals. But all of these methods are batch methods that produce vanishingly small amounts of the stuff.
The method [Chris Sorenson] et al of Kansas State University developed, which involves detonating acetylene and oxygen in a sturdy pressure vessel with a spark plug, can produce grams of graphene at a go. And what’s more, as their patent application makes clear, the method is amenable to a continuous production process using essentially an acetylene-fueled internal combustion engine.
While we can’t encourage our readers to build an acetylene bomb in the garage, the process is so simple that it would be easily replicated. We wonder how far down it could scale for safety and still produce graphene. Obviously, be careful if you choose to replicate this experiment. If you don’t like explosions and can source some soybean oil and nickel foil, maybe try this method instead. Then you’ll have something to mix with your Silly Putty.
Continue reading “Explosive New Process Produces Graphene by the Gram”
High-altitude balloons are used to perform experiments in “near space” at 60,000-120,000 ft. (18000-36000m). However, conditions at such altitude are not particularly friendly and balloons have to compete with ultraviolet radiation, bad weather and the troubles of long distance communication. The trick is to send up a live entity to make repairs as needed. A group of students from Stanford University and Brown University repurposed nature in their solution. Enter Bioballoon: a living high-altitude research balloon.
Instead of using inorganic materials, the Stanford-Brown International Genetically Engineered Machine (iGEM) team designed microbes that grow the components required to build various tools and structures with the hope of making sustained space research feasible. Being made of living material, Bioballoon can be grown and re-grown with the same bacteria, lowering the cost of manufacturing and improving repeatability.
Bioballoon is engineered to be modular, with different strains of bacteria satisfying different requirements. One strain of bacteria has been modified to produce hydrogen in order to inflate the balloon while the balloon itself is made of a natural Kevlar-latex mix created by other cells. Additionally, the team is using Melanin, the molecule responsible for skin color and our personal UV protection to introduce native UV resistance into the balloon’s structure. And, while the team won’t be deploying a glider, they’ve designed biological thermometers and small molecule sensors that can be grown on the balloon’s surface. They don’t have any logging functionality yet, but these cellular hacks could amalgamate as a novel scientific instrument: cheap, light and durable.
Living things too organic for your taste? Don’t worry, we’ve got some balloons that won’t grow on you.
Continue reading “Living High-Altitude Balloon”
True graphene is a one-atom thick layer of carbon. It’s incredibly conductive, transparent, and of course thin. It’s one of those materials that, if it were only cheaper, would be used in everything from batteries to water filtration. Researchers from CSIRO in Australia have found a novel, dirt-cheap, and simple way to make graphene, and it’s hacker-friendly, for certain values of hacker.
The method is to take a sheet of polycrystalline nickel foil, spread a thin layer of soybean oil on it, and heat it up to 800° C for three minutes. It’s cooled off, slid off the foil, and it’s done. While 800° is a lot hotter than a standard toaster oven, their setup isn’t really all that much different. Notably lacking are things like esoteric gasses, partial vacuums, and the like. The nickel foil has some kind of catalytic role in the process — you should read the original if you’re more of a chemist than we are. Continue reading “Graphene? Soybean!”
See those blue and green dots in the GIF? Those aren’t pixels on an LCD display. Those are actual drops of liquid moving across a special PCB. The fact that the droplets are being manipulated to play a microfluidics game of “Frogger” only makes OpenDrop v 2.0 even cooler.
Lab biology is mainly an exercise in liquid handling – transferring a little of solution X into some of solution Y with a pipette. Manual pipetting is tedious, error prone, and very low throughput, but automated liquid handling workstations run into the hundreds of thousands of dollars. This makes [Urs Gaudenz]’s “OpenDrop” microfluidics project a potential game changer for the nascent biohacking movement by offering cheap and easy desktop liquid handling.
Details are scarce on the OpenDrop website as to exactly how this works, but diving into the literature cited reveals that the pads on the PCB are driven to high voltages to attract the droplets. The PCB itself is covered with a hydrophobic film – Saran wrap that has been treated with either peanut oil or Rain-X. Moving the droplets is a simple matter of controlling which pads are charged. Splitting drops is possible, as is combining them – witness the “frog” getting run over by the blue car.
There is a lot of cool work being done in microfluidics, and we’re looking forward to see what comes out of this open effort. We’ve covered other open source efforts in microfluidics before, but this one seems so approachable that it’s sure to capture someone’s imagination.
Continue reading “Microfluidics “Frogger” is a Game Changer for DIY Biology”