Calling [Matt Barr]’s remote controlled hot air balloon a miniature is a bit misleading. Sure, it’s small compared with the balloons that ply cold morning skies with paying passengers and a bottle of champagne for the landing. Having been in on a few of those landings, we can attest to the size of the real thing. They’re impressively big when you’re up close to them.
While [Matt]’s balloon is certainly smaller, it’s not something you’d just whip together in an afternoon. Most of [Matt]’s build log concentrates mainly on the gondola and its goodies — the twin one-pound camp stove-style propane tanks, their associated plumbing, and the burner, a re-tasked propane weed torch from Harbor Freight. Remote control is minimal; just as in a full-size balloon, all the pilot can really do is turn the burner on or off. [Matt]’s approach is a high-torque RC servo to control the burner valve, which is driven by an Arduino talking to the ground over a 2.4-GHz RF link. The balloon is big enough to lift 30 pounds and appears to be at least 12 feet tall; we’d think such a craft would run afoul of some civil aviation rules, so perhaps it’s best that the test flight below was a tethered one.
We’ve had our eye on [Greg Zumwalt]. He’s been working on some very clever 3D-printed mechanisms and his latest prototype is an air engine for a toy car. You can supply the air for the single cylinder with a compressor, or by blowing into it, but attaching an inflated balloon makes the system self-contained.
Last week we saw the prototype of the engine by itself, and wondered if this had enough power to drive a little train engine. We were almost right as here it is powering the front wheels of a little car.
This isn’t [Greg’s] first rodeo. He’s been working on self-contained locomotion for a while now. Shown here is his spring-driven car which you pull backwards to load the spring. It’s a common feature in toys, and very neat to see with the included 3D-printed spring hidden inside of the widest gear.
That print looks spectacular, but the balloon-powered prototype tickles our fancy quite a bit more. Make sure you have your sound on when you watch the video after the break. It’s the chuga-chuga that puts this one over the top. [Greg] hasn’t yet posted files so you can print your own (it’s still a prototype) but browse the rest of his designs as you wait — they’re numerous and will bring an even bigger smile to your face. Remember that domino-laying LEGO bot [Matthias Wandel] built a few years back? [Greg] has a printable model for it!
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.
No matter whether you call them “picosatellites” or “high altitude balloons” or “spaceblimps”, launching your own electronics package into the air, collecting some high-altitude photos and data, and then picking the thing back up is a lot of fun. It’s also educational and inspirational. We’re guessing that 264 students from 30 high schools in Aguascalientes Mexico have new background screens on their laptops today thanks to the CatSat program (translated here by robots, and there’s also a video to check out below).
High-altitude balloon flights have become somewhat of a known quantity these days. Although it’s still a fun project that’ll bring your hackerspace together on a complex challenge, after the first balloon or two, everyone starts to wonder”what next?”. Higher? Faster? Further? Cheaper? More science? There are a variety of different challenges out there.
A group of Stanford students just bagged a new record, longest time in flight, with their SSI-41 mission. In addition to flying from coast to coast, on a track that went waaaay up into Canadian airspace, they logged 79 hours of flight time.
The secret? Val-Bal. A “valve ballast” gas venting valve and ballast dispenser system that kept the balloon from going too high (and popping) or dropping back down to earth. The balance seems to have worked nearly perfectly — check the altitude profile graph. We’d love to see more details about this system. If anyone out there on the team does a writeup, let us know?
There are as many interesting ways to get into high-altitude ballooning as there are hackers. We love the extreme economy of the Pico Space Balloon project, which has gone around the world (twice!) on a solar-powered party balloon. And we’ll give both the best-name and ridiculous-concept awards to the Tetroon. But for now, most time aloft goes to the Stanford team. Congrats!
At my university, we were all forced to take a class called Engineering 101. Weirdly, we could take it at any point in our careers at the school. So I put it off for more interesting classes until I was forced to take it in one of my final years. It was a mess of a class and never quite seemed to build up to a theme or a message. However, every third class or so they’d dredge up a veritable fossil from their ranks of graduates. These greybeards would sit at the front of the class and tell us about incredible things. It was worth the other two days of nondescript rambling by whichever engineering professor drew the short straw for one of their TAs.
One greybeard in particular had a long career in America’s unending string of, “Build cool stuff to help us make bad guys more deader,” projects. He worked on stealth boats, airplanes with wings that flex, and all sorts of incredibly cool stuff. I forgot about the details of those, but the one that stuck with me was the Cyclocrane. It had a ton of issues, and as the final verdict from a DARPA higher-up with a military rank was that it, “looked dumb as shit” (or so the greybeard informed us).
The Cyclocrane was a hybrid airship. Part aerodynamic and part aerostatic, or more simply put, a big balloon with an airplane glued on. Airships are great because they have a constant static lift, in nearly all cases this is buoyancy from a gas that is lighter than air. The ship doesn’t “weigh” anything, so the only energy that needs to be expended is the energy needed to move it through the air to wherever it needs to go. Airplanes are also great, but need to spend fuel to lift themselves off the ground as well as point in the right direction. Helicopters are cool because they make so much noise that the earth can’t stand to be near them, providing lift. Now, there’s a huge list of pros and cons for each and there’s certainly a reason we use airplanes and not dirigibles for most tasks. The Cyclocrane was designed to fit an interesting use case somewhere in the middle.
In the logging industry they often use helicopters to lift machinery in and out of remote areas. However, lifting two tons with a helicopter is not the most efficient way to go about it. Airplanes are way more efficient but there’s an obvious problem with that. They only reach their peak efficiency at the speed and direction for which their various aerodynamic surfaces have been tuned. Also worth noting that they’re fairly bad at hovering. It’s really hard to lift a basket of chainsaws out of the woods safely when the vehicle doing it is moving at 120mph.
The cyclocrane wanted all the efficiency of a dirigible with the maneuverability of a helicopter. It wanted to be able to use the effective lifting design of an airplane wing too. It wanted to have and eat three cakes. It nearly did.
A Spinning Balloon with Wings
Four wings stick out of a rotating balloon. The balloon provides half of the aerostatic lift needed to hold the plane and the cargo up in the air. The weight is tied to the static ends of the balloon and hang via cables below the construction. The clever part is the four equidistant wings sticking out at right angles from the center of the ship. At the tip of each wing is a construction made up of a propellor and a second wing. Using this array of aerofoils and engines it was possible for the cyclocrane to spin its core at 13 revolutions per minute. This produced an airspeed of 60 mph for the wings. Which resulted in a ton of lift when the wings were angled back and forth in a cyclical pattern. All the while, the ship remaining perfectly stationary.
Now the ship had lots of problems. It was too heavy. It needed bigger engines. It was slow. It looked goofy. It didn’t like strong winds. The biggest problem was a lack of funding. It’s possible that the cyclocrane could have changed a few industries if its designers had been able to keep testing it. In the end it had a mere seven hours of flying time logged with its only commercial contract before the money was gone.
However! There may be some opportunity for hackers here. If you want to make the quadcopter nerds feel a slight sting of jealousy, a cyclocrane is the project for you. A heavy lift robot that’s potentially more efficient than a balloon with fans on it is pretty neat. T2here’s a bit of reverse engineering to be done before a true performance statement can be made. If nothing else. It’s just a cool piece of aerospace history that reminds us of the comforting fact that we haven’t even come close to inventing it all yet.
If you’d like to learn more there’s a ton of information and pictures on one of the engineer’s website. Naturally wikipedia has a bit to say. There’s also decent documentary on youtube, viewable below.
Launching a high altitude balloon requires a wide breadth of knowledge. To do it right, you obviously need to know electronics and programming to get temperature, pressure, and GPS data. You’ll have to research which cameras will take good pictures and are easily programmable. It’s cold up there, and that means you need some insulation to keep the batteries warm. If you ever want to find your payload, you’ll also need an amateur radio license.
This flight data recorder for balloons is based on the ever popular ATMega328, and includes humidity, temperature, pressure, accelerometer, gyroscope, and magnetometer sensors. All of this data is recorded to an SD card. The Real Engineers™ who are wont to criticize design decisions they disagree with might laugh at the use of a 7805 voltage regulator, but in this case it makes a lot of sense. The power wasted by a linear regulator isn’t. It’s turned into heat which keeps the batteries alive a little bit longer.
This balloon data recorder has already flown, and [Jeremy] got some great pictures out of it. It’s a great piece of the puzzle for an exceptionally multidisciplinary project, and a great entry for the Hackaday Prize.