Simple Demo Shows The Potential Of Magnetic Gears

April 13, 2020 by Dan Maloney 27 Comments

We’ve probably all used gears in our projects at one time or another, and even if we’re not familiar with the engineering details, the principles of transmitting torque through meshed teeth are pretty easy to understand. Magnetic gears, though, are a little less intuitive, which is why we appreciated stumbling upon this magnetic gear drivetrain demonstration project.

[William Fraser]’s demo may be simple, but it’s a great introduction to magnetic gearing. The stator is a block of wood with twelve bolts to act as pole pieces, closely spaced in a circle around a shaft. Both ends of the shaft have rotors, one with eleven pairs of neodymium magnets arranged in a circle with alternating polarity, and a pinion on the other side of the stator with a single pair of magnets. When the pinion is spun, the magnetic flux across the pole pieces forces the rotor to revolve in the opposite direction at a 12:1 ratio.

Watching the video below, it would be easy to assume such an arrangement would only work for low torque applications, but [William] demonstrated that the system could take a significant load before clutching out. That could even be a feature for some applications. We’ve got an “Ask Hackaday” article on magnetic gears if you want to dive a little deeper and see what these interesting mechanisms are good for.

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High Tech Tagging Adds Graffiti To Poles

November 23, 2012 by Mike Szczys 38 Comments

[Akira] looks to increase his urban canvas by tagging poles which some custom hardware. If you’re looking to add some art to a lamp post, height becomes a problem. That’s where this little guy comes in. The remote-controlled pole climber includes a marker that leaves a trail as the device climbs and descends.

The rig clamps around a pole, with omnidirectional bearings on three sides of the four-sided frame. That last side is occupied by a rubber wheel mounted at a bit of an angle. When the motor turns the angle of the wheel causes the jig to rotate around the pole and climb at the same time. To come back down the motor is simply reversed. Xbee modules are used to make a rudimentary wireless control with a button for up and another for down. It looks like the marker is also mounted on a servo but we didn’t see a way to control when it is actually touching the pole. Perhaps you can figure it out by studying the clip after the jump.

We’ve seen projects that climb poles before. Among our favorites is the one that takes your bicycle with it.

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Ski Pole Persistence Of Vision

February 16, 2011 by Mike Szczys 6 Comments

[Powder4u] wanted to make a persistence of vision display for his bicycle but with 50 cm of snow on the ground it’s hard to get out and ride right now. Instead he made this persistence of vision ski-pole accessory. We asked him to share some details and he obliged. It’s made using an Arduino compatible ATmega168, LEDs with resistors, and installed on some protoboard. The enclosure is a clear pencil case, which isn’t water tight but he’s tried to bolster that with some creative scotch tape placement. There’s no sensor to detect which direction the board is moving in so displaying alpha-numeric messages will have some issues, but as you can see he managed to display image data without issue.

We’re used to night skiing with floodlights along the slopes. This would be a fun little thing to have along with you on those dark lift rides.

Climbing Bike Storage Thwarts Thieves?

November 29, 2010 by Mike Szczys 51 Comments

If you’ve got an expensive bike and don’t mind carrying around a whole bunch of extra weight in your courier bag you’ll like this concept. A design team built a pole-climbing bike rack in about 14 days. The video after the break shows the prototyping process as well as the finished “lock” in use. It’s a commercial for the company that employs the designers, but this is one kind of advert we don’t mind watching.

Square channel makes up the body of the device, with a set of Rollerblade wheels which grab a light pole and use three 12V gear motors for climbing. The controller is a wireless fob similar to those used for keyless entry on cars. In the video you can hear the cliché sound of a car alarm being set once the carrier reaches its finished height. Nice.

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