Electric motors are easy to make; remember those experiments with wire-wrapped nails? But what’s easy to make is often hard to engineer, and making a motor that’s small, light, and powerful can be difficult. [Carl Bugeja] however is not one to back down from a challenge, and his tiny “jigsaw” PCB motor is the latest result of his motor-building experiments.
We’re used to seeing brushless PCB motors from [Carl], but mainly of the axial-flux variety, wherein the stator coils are arranged so their magnetic lines of force are parallel to the motor’s shaft – his tiny PCB motors are a great example of this geometry. While those can be completely printed, they’re far from optimal. So, [Carl] started looking at ways to make a radial-flux PCB motor. His design has six six-layer PCB coils soldered perpendicular to a hexagonal end plate. The end plate has traces to connect the coils in a star configuration, and together with a matching top plate, they provide support for tiny bearings. The rotor meanwhile is a 3D-printed cube with press-fit neodymium magnets. Check out the build in the video below.
Connected to an ESC, the motor works decently, but not spectacularly. [Carl] admits that more tweaking is in order, and we have little doubt he’ll keep optimizing the design. We like the look of this, and we’re keen to see it improved.
Continue reading “Jigsaw Motor Uses PCB Coils For Radial Flux”
It seems these days that the news is never good. Speaking from experience, that’s really nothing new; there’s always been something to worry about, and world leaders have always been adept at playing the games that inevitably lead to disturbing news. Wars always result in the very worst news, of course, and putting any kind of modifier in front of the word, like “Cold” or “proxy”, does little to ameliorate the impact.
And so the headlines have been filled these last months with stories of trade wars, with the primary belligerents being the United States and China. We’ve covered a bit about how tariffs, which serve as the primary weapons in any trade war, have impacted the supply of electronic components and other materials of importance to hackers.
But now, as the trade war continues, a more serious front is opening up, one that could have serious consequences not just to the parties involved but also to the world at large. The trade war has escalated to include rare earth metals, and if the threats and rumors currently circulating come to fruition, the technologies and industries that make up the very core of modern society will be in danger of grinding to a halt, at least temporarily.
Continue reading “Rare Earth Metals Caught In Trade War”
Hackaday regular [Mikey Sklar] is no stranger to body modifications. He enjoys tweaking his body in ways that help him with day to day tasks, including a ruler tattoo on his arm and an RFID chip embedded in the web of his hand. Lately, he has been toying around with a less invasive means of getting a better feel for magnetic fields in his surroundings.
Turned on to magnetic rings by a friend, he now wears an epoxy-coated rare earth ring every day, changing the way he interacts with the world. He says that besides the obvious ability to tell when he’s near iron-heavy material, he can also feel cell phone calls, as the speaker draws the ring closer while producing sound.
He says that holding the electric cord of his tea kettle gave him the biggest start, making him feel as if he had been electrocuted, minus the actual shock.
While it’s not the most high-tech hack, [Mikey] is quite happy with the “sixth sense” this reasonably price ring has been able to provide – we just might have to try it out ourselves.
This hack’s old as dirt to be sure, but new to us and a great accomplishment. The plane above, which is meant to fly without an operator, has been given RC control thanks to parts from that little car. The transmitter and receiver pair are the obvious transplant, but how do you add steering to a $7 plane that wasn’t manufactured to have that feature? The tail was cut and reconnected with mylar hinges to turn it into a rudder. A rare earth magnet and a coil are also thrown into the mix to provide movement. Basically this is a simple solenoid where the coil pushes against the magnet when energized, actuating the rudder. This in combination with an upgraded motor allows for both speed control and yaw. It doesn’t look like you can control roll and pitch but what more can you really expect?
This would be a nice first step on that path to building an epic flying camera rig.
Your hamster lives to good life, with food delivery and a maid service that cleans up after him. [DanF] helped to brighten up this hamster’s life even more by improving its exercise equipment and giving it a small night-light as well. This project adds a low RPM alternator to the hamster wheel.
The first part of the process was to reduce energy lost to friction by fitting the wheel with a bearing. From there a ring of permanent magnets was added which will pass by a stationary coil and induce a current. It works, but unfortunately there’s not enough power generated to charge a battery. That means the light is only on when the hamster is running. But maybe you can figure out a way to use a super-capacitor like we saw in that exercise bike hack.
One nice finishing touch to the setup is a bicycle computer to track how much time was sent on the wheel, and the distance traveled.
Slow day at the office? Here’s a trick that’ll make your coworkers smile. Dangerously Fun has a guide to build a homopolar motor from a battery, copper wire, and magnet. A homopolor motor doesn’t rely on electromagnets in an armature changing their polarity to force a rotation movement compared to stationary magnets. Instead, they use an electrical current’s orientation to a magnetic field to provide a repulsive or rotational force. In this implementation, the current moves through a loops of copper wire from one pole of a battery to the other. A rare-earth magnet on one pole of the battery provides the magnetic field.
After the break we’ve embedded video of this simple example as well as a few more complex homopolar examples such as a five speed version. The motor in action certainly brings a smile to our faces and places this firmly in the useless machines family of hacks.
Continue reading “Homopolar Motor”