Robot Jellyfish Fueled By Hydrogen From The Water Around It

March 22, 2012 by 26 Comments

RoboJelly is certainly not what we’re used to seeing when it comes to robots. Instead of a cold metallic skeleton, this softie is modeled after jellyfish which have no bones. But that’s not the only thing that’s unusual about it. This robot also doesn’t carry its own power source. It gets the energy needed for locomotion from the water around it.

Artificial muscles are what give this the movement seen in the clip after the break. These muscles react to heat, and that heat is produced through a chemical reaction. The construction method starts with the muscle material, which is then covered in carbon nanotubes, and finally coated with black platinum dust. Sounds a bit like witchcraft, huh (Eye of newt, dragon heart string, etc.)? We certainly don’t have the chemistry background to understand how this all works. But we are impressed. So far it doesn’t have the ability to change direction, the flexing of all of the muscle material happens at the same time. But the next step in their research will be finding a way to route the “fuel” to give it some direction.

Edit – Looks like it is fueled externally. The actual study is here, but you need to log in to download it.

This brings another jellyfish-inspired robot to mind. Check out FESTO’s offering which flies through the air with the greatest of ease.

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Blue Alchemist Promises Rocket Fuel From Moon Dust

September 22, 2025 by 16 Comments

Usually when an alchemist shows up promising to turn rocks into gold, you should run the other way. Sure, rocket fuel isn’t gold, but on the moon it’s worth more than its weight in the yellow stuff. So there would be reason to be skeptical if this “Blue Alchemist” was actually an alchemist, and not a chemical reactor under development by the Blue Origin corporation.

The chemistry in question is quite simple, really: take moon dust, which is rich in aluminum silicate minerals, and melt the stuff. Then it’s just a matter of electrolysis to split the elements, collecting the gaseous oxygen for use in your rockets. So: moon dust to air and metals, just add power. Lots and lots of power.

Melting rock takes a lot of temperature, and the molten rock doesn’t electrolyse quite as easily as the water we’re more familiar with splitting. Still, it’s very doable; this is how aluminum is produced on Earth, though notably not from the sorts of minerals you find in moon dust. Given the image accompanying the press release, perhaps on the moon the old expression will be modified to “make oxygen while the sun shines”.

Hackaday wasn’t around to write about it, but forward-looking researchers at NASA, expecting just such a chemical reactor to be developed someday, proposed an Aluminum/Liquid Oxygen slurry monopropellant rocket back in the 1990s.

That’s not likely to be flying any time soon, but of course even with the Methalox rockets in vogue these days, there are appreciable cost savings to leaving your oxygen and home. And we’re not biologists, but maybe Astronauts would like to breathe some of this oxygen stuff? We’ve heard it’s good for your health.

A photo montage of scrap plastic being vacuumed up, processed in the main chamber, and bottled in gas tanks.

Solar Powered Pyrolysis Facility Converts Scrap Plastic Into Fuel

August 23, 2025 by 59 Comments

[naturejab] shows off his solar powered pyrolysis machine which can convert scrap plastic into fuel. According to the video, this is the world’s most complex hand-made pyrolysis reactor ever made. We will give him some wiggle room there around “complex” and “hand-made”, because whatever else you have to say about it this machine is incredibly cool!

As you may know pyrolysis is a process wherein heat is applied to organic material in an inert environment (such as a vacuum) which causes the separation of its covalent bonds thereby causing it to decompose. In this case we decompose scrap plastic into what it was made from: natural gas and petroleum.

His facility is one hundred percent solar powered. The battery is a 100 kWh Komodo commercial power tank. He has in the order of twenty solar power panels laying in the grass behind the facility giving him eight or nine kilowatts. The first step in using the machine, after turning it on, is to load scrap plastic into it; this is done by means of a vacuum pump attached to a large flexible tube. The plastic gets pumped through the top chamber into the bottom chamber, which contains blades that help move the plastic through it. The two chambers are isolated by a valve — operating it allows either chamber to be pumped down to vacuum independently.

Once the plastic is in the main vacuum chamber, the eight active magnetrons — the same type of device you’d find in your typical microwave oven — begin to break down the plastic. As there’s no air in the vacuum chamber, the plastic won’t catch fire when it gets hot. Instead it melts, returning to petroleum and natural gas vapor which it was made from. Eventually the resultant vapor flows through a dephlegmator cooling into crude oil and natural gas which are stored separately for later use and further processing.

If you’re interested in pyrolysis you might like to read Methane Pyrolysis: Producing Green Hydrogen Without Carbon Emissions.

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Ask Hackaday: Where Are All The Fuel Cells?

August 21, 2025 by 61 Comments

Given all the incredible technology developed or improved during the Apollo program, it’s impossible to pick out just one piece of hardware that made humanity’s first crewed landing on another celestial body possible. But if you had to make a list of the top ten most important pieces of gear stacked on top of the Saturn V back in 1969, the fuel cell would have to place pretty high up there.

Apollo fuel cell. Credit: James Humphreys

Smaller and lighter than batteries of the era, each of the three alkaline fuel cells (AFCs) used in the Apollo Service Module could produce up to 2,300 watts of power when fed liquid hydrogen and liquid oxygen, the latter of which the spacecraft needed to bring along anyway for its life support system. The best part was, as a byproduct of the reaction, the fuel cells produced drinkable water.

The AFC was about as perfectly suited to human spaceflight as you could get, so when NASA was designing the Space Shuttle a few years later, it’s no surprise that they decided to make them the vehicle’s primary electrical power source. While each Orbiter did have backup batteries for emergency purposes, the fuel cells were responsible for powering the vehicle from a few minutes before launch all the way to landing. There was no Plan B. If an issue came up with the fuel cells, the mission would be cut short and the crew would head back home — an event that actually did happen a few times during the Shuttle’s 30 year career.

This might seem like an incredible amount of faith for NASA to put into such a new technology, but in reality, fuel cells weren’t really all that new even then. The space agency first tested their suitability for crewed spacecraft during the later Gemini missions in 1965, and Francis Thomas Bacon developed the core technology all the way back in 1932.

So one has to ask…if fuel cell technology is nearly 100 years old, and was reliable and capable enough to send astronauts to the Moon back in 1960s, why don’t we see them used more today?

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A Brief History Of Fuel Cells

May 22, 2025 by 15 Comments

If we asked you to think of a device that converts a chemical reaction into electricity, you’d probably say we were thinking of a battery. That’s true, but there is another device that does this that is both very similar and very different from a battery: the fuel cell.

In a very simple way, you can think of a fuel cell as a battery that consumes the chemicals it uses and allows you to replace those chemicals so that, as long as you have fuel, you can have electricity. However, the truth is a little more complicated than that. Batteries are energy storage devices. They run out when the energy stored in the chemicals runs out. In fact, many batteries can take electricity and reverse the chemical reaction, in effect recharging them. Fuel cells react chemicals to produce electricity. No fuel, no electricity.

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Big Chemistry: Fuel Ethanol

May 21, 2025 by 73 Comments

If legend is to be believed, three disparate social forces in early 20th-century America – the temperance movement, the rise of car culture, and the Scots-Irish culture of the South – collided with unexpected results. The temperance movement managed to get Prohibition written into the Constitution, which rankled the rebellious spirit of the descendants of the Scots-Irish who settled the South. In response, some of them took to the backwoods with stills and sacks of corn, creating moonshine by the barrel for personal use and profit. And to avoid the consequences of this, they used their mechanical ingenuity to modify their Fords, Chevrolets, and Dodges to provide the speed needed to outrun the law.

Though that story may be somewhat apocryphal, at least one of those threads is still woven into the American story. The moonshiner’s hotrod morphed into NASCAR, one of the nation’s most-watched spectator sports, and informed much of the car culture of the 20th century in general. Unfortunately, that led in part to our current fossil fuel predicament and its attendant environmental consequences, which are now being addressed by replacing at least some of the gasoline we burn with the same “white lightning” those old moonshiners made. The cost-benefit analysis of ethanol as a fuel is open to debate, as is the wisdom of using food for motor fuel, but one thing’s for sure: turning corn into ethanol in industrially useful quantities isn’t easy, and it requires some Big Chemistry to get it done.
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Hydrogen Trains: Not The Success Germany Hoped They Would Be

April 29, 2025 by 95 Comments

As transport infrastructure in Europe moves toward a zero-carbon future, there remain a number of railway lines which have not been electrified. The question of replacing their diesel traction with greener alternatives, and there are a few different options for a forward looking railway company to choose from. In Germany the Rhine-Main railway took delivery of a fleet of 27 Alstom hydrogen-powered multiple units for local passenger services, but as it turns out they have not been a success (German language, Google translation.). For anyone enthused as we are about alternative power, this bears some investigation.

It seems that this time the reliability of the units and the supply of spare parts was the issue, rather than the difficulty of fuel transport as seen in other failed hydrogen transport problems, but whatever the reason it seems we’re more often writing about hydrogen’s failures than its successes. We really want to believe in a hydrogen future in which ultra clean trains and busses zip around on hydrogen derived from wind power, but sadly that has never seemed so far away. Instead trains seem inevitably to be following cars, and more successful trials using battery units point the way towards their being the future.

We’re sure that more hydrogen transport projects will come and go before either the technological problems are overcome, or they fade away as impractical as the atmospheric railway. Meanwhile we’d suggest hydrogen transport as the example when making value judgements about technology.