[Jinha Lee] at the MIT Media Lab created a new interface allowing new ways to modify and play with 3D objects. It’s called ZeroN, and it’s nothing short of a futuristic device straight out of Star Trek.
ZeroN is simply a platform for levitating a small spherical permanent magnet in 3D space. It does this by mounting a hall effect sensor on an electromagnet. The hall sensor measure the strength of the magnetic field of the ball every few milliseconds and keeps the spherical magnet levitated. To move the object in 3D space, a few webcams track the ball over the platform and tell the electromagnet to move on a CNC-like x y table.
[Jinha] showed off a lot of cool stuff that is possible with the ZeroN; ping-pong is by far the coolest implementation, but it’s also possible to use the magnetic sphere to demonstrate n-body gravity or as a camera flying around a digital scene.
It’s a really amazing piece of work with an exceptional demo video. You can check that video out after the break. Thanks, [ferdinand] for sending this one in.
Here’s an impressive example of a completely home built magnetic levitation setup… with wireless power transmission to boot!
[Samer] built this from scratch and it features two main sub-systems, a electromagnet with feedback electronics and a wireless power transfer setup.
The ring of LEDs has a stack of neodymium magnets which are levitated in place by a varying magnetic field. This levitation is achieved by using a Hall effect sensor and a PID controller using a KA7500 SMPS controller.
The wireless power transmission uses a Class E DC/AC inverter that operates at 800KHz. Two coils of wire pass the current between the stand and the LEDs.
It’s very similar to a build we featured last year, but it’s a great hack, so we had to share it! Check out the video after the break.
[Davide] saw our recent post on magnetic levitation and quickly sent in his own project, which has a great explanation of how it works — he’s also included the code to try yourself!
His setup uses an Atmega8 micro-controller which controls a small 12V 50N coil using pulse-width-modulation (PWM). A hall effect sensor (Allegro A1302) mounted inside the coil detects the distance to the magnet and that data is used by a PID controller to automatically adjust the PWM of the coil to keep the magnet in place. The Atmega8 runs at 8Mhz and the hall effect sensor is polled every 1ms to provide an updated value for the PWM. He’s also thrown in an RGB LED that lights up when an object is being levitated!
So why is there a kid with a floating balloon? [Davide] actually built the setup for his friend [Paolo] to display at an art fair called InverART 2013!
After the break check out the circuit diagram and a short demonstration video of the device in action!
Oh yeah, those of you not impressed by magnetic levitation will probably appreciate acoustic levitation.
Let’s face it, levitating anything is pretty fascinating — especially when you think there should be wires. This project puts a new spin on magnetic levitation by using a PID controller to levitate a speaker while it plays music!
It uses the standard levitation setup — an electromagnet, a permanent magnet, and a hall effect sensor. A microcontroller implements the PID system, varying the current supplied to the electromagnet to keep the speaker floating at just the right height. Music is wirelessly transmitted to the speaker via Bluetooth, but unfortunately the speaker’s power is not. It features a small lithium ion battery which has a run-time of around 5 hours before it has to be recharged manually.
As you’ll notice in the following video, having a floating speaker has a pretty interesting effect — especially when it starts spinning.
It is possible to also wirelessly transmit power, like this floating LED project we saw awhile ago — but either way, it’s pretty cool.
Press embargoes lifted today, heralding the announcement of the world’s first hoverboard. Yes, the hovering skateboard from Back to the Future. It’s called the Hendo hoverboard, it’s apparently real, and you can buy one for $10,000. If that’s too rich for your blood, you can spend $900 for a ‘technology demonstrator’ – a remote-controlled hovering box powered by the same technology.
Of course the world’s first hoverboard is announced to the world as a crowd funding campaign, so before we get to how this thing is supposed to work, we’ll have to do our due diligence. The company behind this campaign, Arx Pax Labs, Inc, exists, as does the founder. All the relevant business registration, biographical information, and experience of the founder and employees of Arx Pax check out to my satisfaction. In fact, at least one employee has work experience with the innards of electric motors. At first glance, the company itself is actually legit.
The campaign is for a BttF-style hoverboard, but this is really only a marketing strategy for Arx Pax; the hoverboards themselves are admittedly loss leaders even at $10,000 – the main goal of this Kickstarter is simply to get media attention to the magnetic levitation technology found in the hoverboard. All of this was carefully orchestrated, with a ‘huge event’ to be held exactly one year from today demonstrating a real, working hoverboard. What’s so special about demoing a hoverboard on October 21, 2015?
I defy anyone to come up with a better marketing campaign than this.
The meat of the story comes from what has until now been a scientific curiosity. Everyone reading this has no doubt seen superconductors levitated off a bed of magnets, and demonstrations of eddy currents are really just something cool you can do with a rare earth magnet and a copper pipe. What [Greg Henderson] and Arx Pax have done is take these phenomena and turned them into a platform for magnetic levitation.
According to the patent, the magnetic levitation system found in the Hendo hoverboard works like this:
One or more electric motors spin a series of rotors consisting of an arrangement of strong permanent magnets.
The magnets are arranged in a Halbach array that enhances the magnetic field on one side of the array, and cancels it on the other.
By placing the rotors over a conductive, non-ferrous surface – a sheet of copper or aluminum, for example – eddy currents are induced in the conductive surface.
These eddy currents create a magnetic field that opposes the magnetic field that created it, causing the entire device to levitate.
That’s it. That’s how you create a real, working hoverboard. Arx Pax has also developed a method to control a vehicle equipped with a few of these hover disks; the $900 ‘Whitebox’ technology demonstrator includes a smart phone app as a remote control.
If you’re still sitting in a steaming pile of incredulity concerning this invention, you’re in good company. It’s a fine line between being blinded by brilliance and baffled by bullshit, so we’re leaving this one up to you: build one of these devices, put it up on hackaday.io, and we’ll make it worth your while. We’re giving away some gift cards to the Hackaday store for the first person to build one of these hoverboards, preferably with a cool body kit. The Star Wars landspeeder has already been done, but the snowspeeder hasn’t. Surprise us.
Three days ago on October 21, 2014 it was announced to the world the Back to the Future hoverboard was real. It’s a Kickstarter, of course, and it’s trending towards a $5 Million dollar payday for the creator. Surprisingly for a project with this much marketing genius, it’s a real, existing device and there’s even a patent. From the patent, we’re able to glean a few details of how this hoverboard/magnetic levitation device works, and in our post on the initial coverage, we said we’d be giving away some goodies to the first person who can clone this magnetic levitation device and put it up on hackaday.io.
[jellmeister] just won the prize. It’s somewhat cheating, as he’s had his prototype hoverboard working in July, and demoed a more advanced ‘upside-down quadcopter’ device at the Brighton Mini Maker Faire in September. Good on ‘ya [jelly]. You’re getting a gift card for the hackaday store.
Like the Kickstarter hoverboard, [jelly] is using an array of magnets rotating in a frame above a non-ferrous metal. For the initial test, eight neodymium magnets were arranged in a frame, suspended over 3/4″ aluminum plate, and spun up with a drill. With just this simple test, [jelly] was able to achieve 2kg of lift at 1cm and 1kg of lift at 1 inch of separation. This test also provided some valuable insight on what the magnets do to the aluminum or copper; the 3kg aluminum plate was nearly spinning, meaning if this device were to be used on small plates, counter-rotating pairs of magnetic lifters would need to be used.
The test rig then advanced to two pairs of rotors with standard hobby brushless motors, but stability was a problem; the magnetic rotors provided enough lift, but it would quickly fall over. To solve this problem, [jellmeister] took a standard quadcopter configuration, replaced the props with magnetic rotors, and successfully hovered it above a sheet of aluminum at the Brighton Maker Faire.
Since [jellmeister] has actually built one of these magnetically levitating hoverboards, he has a lot more data about how they work than an embargoed press release. The magnetic rotor hoverboard will work on aluminum as well as copper, but [jell] suspects the Kickstarter hoverboard may be operating right at the edge of its performance, necessitating the more efficient copper half pipe. The thickness of the non-ferrous plate also makes a difference, with better performance found using thicker plates. No, you bojo, hoverboards don’t work on salt water, even if you have pow-ah.
So there ‘ya go. That’s how you build a freakin’ hoverboard. [jellmeister]‘s design is a little crude and using a Halbach array for the magnetic rotors should improve efficiency. Using a 3D printed rotor design is a stroke of genius, and we’ll expect a few more quad-magnetic-levitating-things to hit the tip line in short order.
Demos of [jellmeister]‘s work below.
Oh. These things need a name. I humbly submit the term ‘Bojo’ to refer to any device that levitates though rotating magnets and eddy currents.
This past weekend the Maker Faire returned to the motor city. While it seemed a bit smaller than previous years, the event still brought in a ton of awesome makers from the metro Detroit area and beyond.
Although we don’t feature too many woodworking projects, there were quite a few woodworkers at the Faire with projects ranging from custom longboards pressed with a home built iron mold to DIY kayaks with elaborate wooden skeletons built by a local group of Michigan kayak builders. The kayaks were quite impressive: hand sewn nylon panels are wrapped around custom frames made from steamed white oak. It’s great to speak with the makers about the specialized skills needed for kayak building.
A maker from Carleton, MI brought a pretty interesting setup demoing magnetic levitation produced by eddy currents. His simple demo consisted of a swing-arm with a spinning acrylic disk mounted on a brushless motor. Several magnets were attached to the ring in an alternating north/south pattern. When the motor spun up over a copper or aluminum plate, the arm started to hover about a centimeter above the surface. This design is similar to the tech used by the various hoverboard concepts that have been floating around.
To take the design even further, he mounted his homemade “hover engines” on a quadcopter frame. The quadcopter was able to hover over a small aluminum sheet, and although he couldn’t drive the quad around, he was confident that throttling the motors would give some control over steering and thrust. Interestingly enough, the landing gear mounted on the quad is essential: the motors aren’t able to spin up when the disks are very close to the surface. To get around this, the quad stays up on its wheels while the motors spin up, and then it lowers down and begins to hover.
There was also an interesting demo of sensing muscle activity with EMG (electromyography). There are a few EMG kits and dev boards out there that amplify your body’s signals to usable levels, but you can easily get the job done with a couple electrodes and some op-amps like this maker did. If you’re interested in getting started with EMG, check out some posts that we’ve featured before.
While software projects aren’t nearly as eye-catching as hardware and mechanical projects seen around the Faire, the guys from MakerOS made a good showing. They are a small software company out of Detroit that is working on web-based backend for Maker-style businesses (which we’ve written about before). Their software runs a couple 3d printing companies in the Detroit area, and they just opened up a beta if you want to check it out for yourself.
Another group was showcasing a submersible prototype. The entire (fairly large) chassis is 3d printed and uses a singe thruster mounted in the front of the vehicle. The thruster pushes water rearwards, which is routed through 4 different butterfly valves that the team designed. The valves essentially vector the thrust, and allow the submersible to be steered without multiple thrusters or any other control surfaces. The team’s website is incredibly vague, but they said they would be releasing more information soon.
Getting a magnetic field to balance on another magnetic field is about as easy as balancing a bowling ball on the tip of an ink pen. With a little help from an Arduino mega, however, [EmmaSong] was able to balance a high density neodymium magnet in midair. He pulled off this tricky project using a set of four coils he got off of Taobao (the Chinese version of eBay), a hall effect sensor, and a handful of current regulation ICs.
The coils can be made in house if necessary, with each winding getting about 800 turns of enameled wire. The rest of the circuit is straightforward. It appears he uses a potentiometer for a rough regulation of the current going to the coils, doing the fine tuning in the code which can be found here (.RAR direct download).
We’ve seen magnetic levitation here before, and this project adds to the list of successful techniques to accomplish this difficult project.
It always surprises us that magnetic levitation seems to have two main purposes: trains and toys. It is reasonably inexpensive to get floating Bluetooth speakers, globes, or just floating platforms for display. The idea is reasonably simple, especially if you only care about levitation in two dimensions. You let an electromagnet pull the levitating object (which is, of course, ferrous). A sensor detects when the object is at a certain height and shuts off the magnet. The object falls, which turns the magnet back on, repeating the process. If you do it right, the object will reach equilibrium and hover near the sensor.
Some students at Cornell University decided to implement the control loop to produce levitation using an Altera FPGA. An inductive sensor determined the position of an iron ball. The device uses a standard proportional integral derivative (PID) control loop. The control loop and PWM generation occur in the FPGA hardware. You can see a video of their result, below.
However, the team also wanted to display data on a VGA screen. While it is possible to do this without a computer, it is much easier to write some software for this task, so the device has an embedded NIOS II processor core that handles tasks including displaying data and changing PID constants.
This project is a good example of marrying FPGA logic for high speed and a CPU for easier development. The sensor and other factors meant the ball didn’t have good control laterally, so the device uses a tube to constrain the ball.
It always seems odd to us that magnetic levitation seems to only find use in big projects (like trains) and in toys. Surely there’s a practical application that fits on our desktop. This isn’t it, but it is a cool way to turn a cheesy-looking levitating globe into a pretty cool Star Wars desk toy.
As projects go, this isn’t especially technically challenging, but it is a great example of taking something off the shelf and hacking it into something else. The globe covering came off, revealing two hemispheres. A circular hole cut out and inverted provides the main weapon. Some internal lighting and small holes provide light. Some fiber optic sanded and tinted green make the weapon fire. The rest is all in the painting.
There’s even a tiny imperial ship orbiting the killer man-made (or is that Sith-made) moon. If you want a bigger challenge, you might try bamboo. Or you can go minimalist and let your eyes and brain do most of the work.
Sometimes Hackaday runs in closed-loop mode: one hacker makes something, we post it, another hacker sees it and makes something else, and we post it, spiraling upward to cooler and cooler hacks. This is one of those times.
One of our favorite junk-sound-artists and musical magicians, [Gijs Gieskes], made this magnetic-levitation, rubber-band, percussive zither thing after seeing our coverage of another magnetic levitation trick. Both of them simply have a Hall sensor controlling a coil, which suspends a magnet in mid-air. It’s a dead-simple circuit that we’ll probably try out as soon as we stop typing.
But [Gijs] took the idea and ran with it. What looks like a paperclip dangles off the magnets, and flails wildly around with its tiny steel arms. These hit a zither made of rubber bands with a bamboo skewer as a bridge, pressing down on a piezo. The rest is cardboard, copper-clad, and some ingenuity. Watch it work in the video embedded below.
What’s fun about this piece is that it’s junk, but it’s animated junk. And it’s got just enough variability and control that it can almost be played intentionally like an instrument. It falls between the cracks, and we like that.
If you want more [Gijs], you can just browse through his website, or check out the incredible TV Flag project, or his fan synth which inspired us to make one of our own (video at the bottom of the post) almost ten years ago now.
It’s time for everyone’s favorite game: speculative engineering! An anonymous reader wrote to our tips line asking how the levitation system of the STORY clock is accomplished. We took a look and can tell you right now… that’s a really good question!
STORY: The Levitating Timepiece has more than a month left on its crowdfunding campaign but it’s reached more than 6x its $80k goal. The wooden disk has a digital time display in the center which is simply an LED matrix just below the wood’s surface. We know how that’s done: wooden veneer with a grid of holes behind to contain the LED light in a perfect circle.
The part that has everyone so excited is a levitating orb that makes a circuit around the face of the clock. It would be easy to guess how it works if this was simply sitting flat on a table (which it can do). But it’s further complicated because it still works when hung on a wall. Most of the DIY levitation rigs we’ve looked at use gravity as an integral aspect of their functionality. A coil is suspended above the object being levitated while a hall-effect sensor tunes the magnetic field to hold the object in place (neither touching the coil, nor falling away from it).
So how is this one doing it? Perhaps there are multiple coils responsible for the levitation, each with their own hall effect sensor. In this scenario, tilting the base to hang on a wall would put different requirements on the coils above and below the magnetic orb. That’s our speculation, what is yours? Does this reasoning hold water magnet? Is there a motorized mechanism inside or does a grid of coils address the movement of the magnetic orb? Let us know in the comments below.
If you’re looking to play with this phenomenon in your own projects, it seems you can buy a magnetic levitation device which exhibits similar properties. The video of this, found in the comments of the STORY Kickstarter page, is embedded below. If you do order one of these, we want to see a teardown!
Unless you’ve been living under a high voltage transformer, you’re aware of the latest release in the Star Wars Saga. [John] has a relative that is clearly a big Star Wars fan, so he set about to build them the perfect Christmas present – a levitating Death Star! Instead of reinventing the wheel, [John] decided to start off with a magnetically levitating model of the Earth – a globe. He then took a Death Star mood lamp and gracefully cut it half with his trusty Dremel.
A nice twist for the mood lamp is that it was powered by a hacker’s best friend – five volts from a USB power supply. This made it easy to wire in a LiPo battery along with a charger and some fiber optic lighting. A pile of cat litter to represent a smoldering planet blown to bits ties the whole build together as only cat litter can.
Be sure to visit [John’s] Instructable page for full details along with a video, which you can also see below.
When we look back to the 1970s it is often in a light of somehow a time before technology, a time when analogue was still king, motor vehicles had carburettors, and telephones still had rotary dials.
In fact the decade had a keen sense of being on the threshold of an exciting future, one of supersonic air travel, and holidays in space. Some of the ideas that were mainstream in those heady days didn’t make it as far as the 1980s, but wouldn’t look out of place in 2018.
The unlikely setting for todays Retrotechtacular piece is the Bedford Levels, part of the huge area of reclaimed farmland in the east of England known collectively as the Fens. The Old Bedford River and the New Bedford River are two straight parallel artificial waterways that bisect the lower half of the Fens for over 20 miles, and carry the flood waters of the River Ouse towards the sea. They are several hundred years old, but next to the Old Bedford River at their southern end are a few concrete remains of a much newer structure from 1970. They are all that is left of a bold experiment to create Britain’s first full-sized magnetic levitating train, an experiment which succeeded in its aim and demonstrated its train at 170 miles per hour, but was eventually canceled as part of Government budget cuts.
A track consisting of several miles of concrete beams was constructed during 1970 alongside the Old Bedford River, and on it was placed a single prototype train. There was a hangar with a crane and gantry for removing the vehicle from the track, and a selection of support and maintenance vehicles. There was an electrical pick-up alongside the track from which the train could draw its power, and the track had a low level for the hangar before rising to a higher level for most of its length.
After cancellation the track was fairly swiftly demolished, but the train itself survived. It was first moved to Cranfield University as a technology exhibit, before in more recent years being moved to the Railworld exhibit at Peterborough where it can be viewed by the general public. The dream of a British MagLev wasn’t over, but the 1980s Birmingham Airport shuttle was hardly in the same class even if it does hold the honour of being the world’s first commercial MagLev.
We have two videos for you below the break, the first is a Cambridge Archaeology documentary on the system while the second is a contemporary account of its design and construction from Imperial College. We don’t take high-speed MagLevs on our travels in 2018, but they provide a fascinating glimpse of one possible future in which we might have.
It does make one wonder: will the test tracks for Hyperloop transportation break the mold and find mainstream use or will we find ourselves 50 years from now running a Retrotechtacular on abandoned, vacuum tubes?
This booth was easy to miss at Maker Faire Bay Area 2019 amidst tall professional conference signage erected by adjacent exhibitors. It showcased the work of [Dr. Victor Chaney] who enjoys his day job as a dentist and thus feels no desire to commercialize his inventions — he’s building fun projects for the sake of personal enjoyment which he simply calls Vic’s Creations. Each project is built to his own standards, which are evidently quite high judging by the perfect glossy finish on every custom wood enclosure.
Some of these creations were aligned with his musical interests. The Backpacking Banjo was built around a (well cleaned) cat food can to satisfy the desire for a lightweight instrument he can take camping. His Musical Laser Rainbow Machine (fully documented in Nuts & Volts) was created so little bands formed by independent artists like himself can have a visual light show to go with their live performances. The Music Kaleidoscope is another execution along similar lines, with an LED array whose colors are dictated by music. Venturing outside the world of music, we see a magnetically levitated Castle In The Clouds which also receives power wirelessly to illuminate LEDs
The largest and most complex work on display is an epic electromechanical masterpiece. Par One is a rolling ball sculpture featuring the most convoluted golf course ever. Several more rolling ball sculptures (also called marble machines or marble runs) are on display at Dr. Chaney’s office which must make it the coolest dentist’s lobby ever. The lifelike motions he was able to get from the automatons he built into the sculpture are breathtaking, as you can see below.
If everything goes according to plan, Elon Musk says the first generation of SpaceX’s massive Starship will make an orbital flight before the end of 2020. That’s a pretty bold claim, but when you’ve made landing rockets on their tails as in the old science fiction pulp magazines seem routine, we suppose you’ve earned the right to a bit of bravado. We’re excited to see the vehicle evolve over the next several months, but even if the real one stays grounded, we’ll gladly take this “flying” Starship model from [Chris Chimienti] as a consolation prize.
A magnetic levitation module, we’re officially in the future.
Feeling a bit let down by the 3D printable models of the Starship he found online, [Chris] set out to build his own. But it wasn’t enough to just make his bigger, stronger, and more accurate to Starship’s current design; he also wanted to make it a bit more exciting. Some RGB LEDs an Arduino embedded in the “cloud” stand the rocket sits on was a good start, and the landing pad inspired by SpaceX’s real autonomous spaceport drone ship Just Read the Instructions looks great all lit up.
But this is Starship we’re talking about, a vehicle that could literally push humanity towards being a multi-planet species. To do it justice, you’ve really got to knock it out of the park. So [Chris] found a magnetic levitation module online that could support a few hundred grams, and set to work on making his plastic Starship actually hover over the landing pad.
As you might imagine, it was a bit tricky. The first versions of the rocket looked great but came out too heavy, so he switched over to printing the model in so-called “spiral vase mode” which made it entirely hollow. Now far lighter and with a magnetic plate fit into the bottom, it was stable enough to float on its own. For the final touch, [Chris] added some red LEDs and a coin cell battery to the base of the Starship so it looks like the sleek craft is performing a last-second landing burn with its “impossible” full-flow staged combustion engines.
This isn’t the first time we’ve seen a model rocket with an electronic glowing cloud under it, but it’s certainly the first one we’ve seen that could levitate in mid-air. While this little rocket might not make it all the way to Mars, we wouldn’t be surprised to see it touching down on the desks of other hackers and makers in the near future.
[Tom Stanton] is right about one thing: flywheels make excellent playthings. Whether watching a spinning top that never seems to slow down, or feeling the weird forces a gyroscope exerts, spinning things are oddly satisfying. And putting a flywheel to work as a battery makes it even cooler.
Of course, using a flywheel to store energy isn’t even close to being a new concept. But the principles [Tom] demonstrates in the video below, including the advantages of magnetically levitated bearings, are pretty cool to see all in one place. The flywheel itself is just a heavy aluminum disc on a shaft, with a pair of bearings on each side made of stacks of neodymium magnets. An additional low-friction thrust bearing at the end of the shaft keeps the systems suitably constrained, and allows the flywheel to spin for twelve minutes or more.
[Tom]’s next step was to harness some of the flywheel’s angular momentum to make electricity. He built a pair of rotors carrying more magnets, with a stator of custom-wound coils sandwiched between. A full-wave bridge rectifier and a capacitor complete the circuit and allow the flywheel to power a bunch of LEDs or even a small motor. The whole thing is nicely built and looks like a fun desk toy.
Maglev trains have long been touted as the new dawn for train technology. Despite keen and eager interest in the mid-20th century, development has been slow, and only limited commercial operations have ever seen service. One of the most well-known examples is the Shanghai Maglev Train which connects the airport to the greater city area. The system was purchased as a turnkey installation from Germany, operates over a distance of just 30.5 km, and according to Civil Engineering magazine cost $1.2 billion to build in 2001. Ever since, it’s served as a shining example of maglev technology — and a reminder of difficult and expensive maglev can be.
However, China has fallen in love with high-speed rail transport in the last few decades and has invested heavily. With an aggressive regime of pursuing technology transfers from foreign firms while building out the world’s largest high-speed rail network, the country has made great progress. Now, Chinese rail transit manufacturer, CRRC Corporation, have demonstrated their newest maglev train, which hopes to be the fastest in the world.
It’s Gonna Be Quick
Improved L0 Series maglev train on its test rack in Japan. [Image by Saruno Hirobano CC-BY-SA 4.0]The aim is to build a maglev train that is capable of speeds up to 600 km/h, which would slash long-distance travel times between major Chinese cities. Such a train would slot neatly in between existing high-speed rail services, which travel at around 350 km/h, and airliners, which travel at around 800-900 km/h. On the crucial Beijing-Shanghai route, travel time could fall from 5.5 hours by train to just 2.5 to 3.5 hours by maglev, depending on who you talk to. That’s only marginally slower than air travel, which takes about 2.5 hours, and that’s ignoring the more arduous security and boarding procedures that are typical when flying.
600km/h is devastatingly fast, and is roughly equal to the current speed record held by the Japanese L0 Series maglev prototype, which achieved 603 km/h on a test track in 2015. The L0 Series holds the current record, and is intended to operate at a speed of 500 km/h in service on the Tokyo-Nagoya line, due to open in 2027.
A maglev train at Longyang Station, Shanghai.
China’s new maglev design, known as the CRRC 600, was first publicised back in 2019. Expected to enter service in 5 to 10 years, it’s a further development of the technology used in the existing Shangai airport link. That train was a turnkey operation bought from German company Transrapid, which has been developing maglev train technology for decades. Our own Mike Szczys travelled on that very system in 2019, which reaches speeds of up to 430km/h in peak hour. CRRC has continued to develop the technology under licence from the owners of Transrapid, Thyssen-Krupp. There has also been discussion of the Chinese operation reopening the original Transrapid test track in Emsland, Germany, which was shut down five years after a fatal accident in 2006.
The Technology
A Transrapid prototype on the test track at its home in Germany. [Source]The Transrapid technology is about as different as possible from conventional railway technology. There are no wheels, and no pantographs to transmit electricity. The train relies on the electromagnetic suspension principle, where powerful electromagnets are used to levitate the vehicle. In the case of the Transrapid, the train has arms which wrap around the guide track with magnets mounted underneath, which are pulled upwards towards the underside of the track. The idea with magnetic levitation is to float the vehicle relative to the track with no direct contact, so a powerful control system is used to carefully maintain the gap between the train and the guide rails by varying the electric current through the train’s levitation coils. Propulsion is via the active guideway linear motor concept. This uses coils in the guideway which are energized in turn to create a travelling magnetic field to push the train along.
The Business Case
The Shanghai Maglev was China’s first step in maglev technology. [Source]The benefits of maglev are decreased noise, higher speeds, and better efficiency by eliminating the friction of wheels running on steel rails. Other than the nascent state of the technology, the primary drawback is cost. It’s not easy to put a number on, though one highly-critical US report cited that maglev can be 1.5 times as costly as regular high-speed rail. The total budget for the Shangai Maglev project was about $1.2 billion for a 30.5 km run, or about $39.3 million per kilometer (including the cost of the two stations). The usual cost of fast rail in China is estimated between $17 and $21 million per kilometer.
The problem is, merely looking at the face value build cost is a poor analysis technique when it comes to transportation systems. Something often forgotten is that a train that travels twice as fast can, theoretically, carry twice as many passengers in the same amount of time. Turnarounds and efficiencies never scale perfectly, but that value must be taken into account. Additionally, dealing with things like steep grades and property acquisition can wildly skew costs from one project, or even one section of track, to another. Other potential bonuses of maglev technology involve lower maintenance costs, due to the non-contact operation of the railway reducing wear. Indeed, in the case of South Korea’s low-speed Incheon maglev railway, the authorities involved claimed the system was significantly cheaper overall than a traditional railway.
Next-Gen Ground Transport Trying to Break Through
Concerns of cost and profitability have kept high speed rail, let alone maglev, from gaining a foothold in places like the US and Australia, despite the potential gains from linking distant cities with something less fussy and more efficient than air travel. Maglev has also vanished from Europe despite Britain and Germany being early pioneers of the technology.
However, China, which is less bothered by such short-sighted concerns, is able to forge ahead with its nation-building project. Lines from Shanghai to Hangzhou and Guangzhou-Shenzhen are likely to be the next candidates to receive maglev lines. These could be amongst the first intercity maglev lines in the world along with the Japanese efforts, and will serve as an important bellwether as for the viability of the technology going forward. If early steps prove successful, expect maglev railways to stretch across China in record time, in much the same vein as high speed rail in the last two decades.
Magnetic levitation is a beautiful thing to watch. Seeing small objects wobble about while seemingly hovering in thin air never gets old. If you want something suitably distracting in this vein for your own desk, consider building this levitating turbine from [JGJMatt].
The build uses a combination of 3D printed parts and metal rods to form a basic frame. The turbine is also 3D printed, making it easy to create the complex geometry for the curved fins. Rare earth magnets are then slotted into the parts in order to create the levitation effect. Two magnets are fitted to each frame piece, and one magnet is inserted into each end of the turbine. When aligned properly, the turbine will hover over the frame and can spin freely with almost no friction.
One concession made to functionality is a sewing needle inserted into the turbine. This presses against one part of the frame in order to keep the turbine from being pushed out of the magnetic field entirely. It’s possible that with very careful attention to detail in alignment, the pin could be eliminated, but it makes the system far more robust and reliable to have it there.
Floating in the magnetic field, a simple puff of air is enough to set the turbine spinning for quite some time. It makes for a captivating desk ornament, and one that can be tinkered with by changing the turbine blades for different performance. It may be frivolous, but at the larger scale, magnetic levitation is put to more serious uses like high-speed transport. Video after the break.
We are big fans of the little desktop magnetic levitation setups that float a small object on a magnet. As [3D Printed Life] points out, they look like magic. He was surprised that the commercial units use analog electronics. He decided to build a digital version but didn’t know what he was getting into. He details his journey in the video you can see below.
Along with a custom control board, he decided to wind his own electromagnets. After finding that tedious he built a simple coil winder to automate some of the work.
If you have ever struggled to find the sweet spot for the magnet on one of these, his first problem was completely predictable. He lost control of the magnet which slammed against the PCB and either physically or electrically damaged the magnetic sensor. After that, he installed a shield to prevent the magnet from directly contacting the board.
The first iteration didn’t work as expected and the magnetic platform kept flipping over. He eventually found a teardown of a commercial unit that showed he needed more stabilizing magnets around the outside of the electromagnets. He also didn’t have the electromagnets set for reversing the polarity.
Solving the polarity problems required repurposing an H bridge circuit that you usually see for motor control. A new board fried after a little testing. Then there was a mechanical failure.
Once the hardware was working, the software posed its own problems. A PID controller wasn’t stable enough. He also tried filtering inputs and adding some other corrections. The platform would float a little but eventually will crash to the electromagnets.
He didn’t get a final working build but he’s hoping someone will be able to give him some advice on getting it working. We figured someone who reads Hackaday has certainly built one of these before and might be able to help.
Three days ago on October 21, 2014 it was announced to the world the Back to the Future hoverboard was real. It’s a Kickstarter, of course, and it’s trending towards a $5 Million dollar payday for the creator. Surprisingly for a project with this much marketing genius, it’s a real, existing device 
Like the Kickstarter hoverboard, [jelly] is using an array of magnets rotating in a frame above a non-ferrous metal. For the initial test, eight neodymium magnets were arranged in a frame, suspended over 3/4″ aluminum plate, and spun up with a drill. With just this simple test, [jelly] was able to achieve 2kg of lift at 1cm and 1kg of lift at 1 inch of separation. This test also provided some valuable insight on what the magnets do to the aluminum or copper; the 3kg aluminum plate was nearly spinning, meaning if this device were to be used on small plates, counter-rotating pairs of magnetic lifters would need to be used.
The part that has everyone so excited is a levitating orb that makes a circuit around the face of the clock. It would be easy to guess how it works if this was simply sitting flat on a table (which it can do). But it’s further complicated because it still works when hung on a wall. Most of the DIY levitation rigs we’ve looked at 
