motor

207 Articles

What Makes Wedge Coils Better Than Round For PCB Motors?

June 2, 2023 by 11 Comments

PCB motors are useful things. With coils printed right on the board, you don’t need to worry about fussy winding jobs, and it’s possible to make very compact, self contained motors. [atomic14] has been doing some work in this area, and decided to explore why wedge coils perform better than round coils in PCB motor designs.

[atomic14]’s designs use four-layer PCBs which allow for more magnetic strength out of the coils made with traces. While they’ve tried a variety of designs, like most in this area, they used wedge-shaped coils to get the most torque out of their motors. As the video explains, the wedge layout allows a much greater packing efficiency, allowing the construction of coils with more turns in the same space. However, diving deeper, [atomic14] also uses Python code to simulate the field generated by the different-shaped coils. Most notably, it shows that the wedge design provides a significant increase in field strength in the relevant direction to make torque, which scales positively on motors with higher numbers of coils.

This kind of simulation and optimization is typical in industry. It’s great to see an explainer on real engineering methods on YouTube for everyone to enjoy. Video after the break.

Continue reading “What Makes Wedge Coils Better Than Round For PCB Motors?” →

Cart Cruises Abandoned California Rail

February 25, 2023 by 21 Comments

Southern California is known for its nearly perfect year-round climate, excellent surf, and extremely high cost of living, but once you get away from the coast things are radically different. Rural California has huge tracts of land run by the Bureau of Land Management (BLM), which is publicly accessible to anyone willing to venture into the deserts. There’s not much in the way of infrastructure out there, but [Ryan] does have a unique way of traveling through it using abandoned railroad lines and this custom rail cart.

The frame of this cart is simple enough, it’s little more than 2×3 framing with a plywood deck. Some extra support is added for the motor mount and for the seating location. It uses slightly longer go-kart axles to accommodate the width of the railroad, and a small six horsepower gas engine with a single gear to power the rear axle. There are no brakes other than the riders’ shoes, and while this all seems straightforward enough the real hack here is [Ryan]’s custom wheels. He found that steel or cast wheels were not particularly comfortable on long journeys so after a few attempts he has come up with a home-built polyurethane wheel which is cast in a mold around a steel go-cart wheel and then trimmed on a lathe.

For pure exploration, there’s almost no better place to go than the American west thanks to all the public BLM land available. In this cart, you can explore long distances using an extremely low-cost method of transportation. We’ve added another video of [Ryan] exploring this area below the break to show the cart being used, too, but if you’d like a more multipurpose vehicle to use on abandoned rail near you, take a look at this bicycle which is converted to operate on the railroad.

Continue reading “Cart Cruises Abandoned California Rail” →

This Electric Outboard Conversion Makes For A Quiet Day On The Water

November 29, 2022 by 21 Comments

Nothing beats a day on the lake in a little boat with an outboard motor putt-putting along behind you. It’s great fun, if perhaps a little noisy with all that putting going on. And maybe that oily sheen on the water in your wake is not so nice. it could be that the fish are a little annoyed with your putting, too. Come to think of it, outboard motors are a bit of a problem.

Fortunately there’s a better way, like converting an old outboard motor to electric. It comes to us by way of [Anton], who happened upon the perfect donor platform — a 5-hp outboard by Crescent, sporting a glorious 1970s color scheme and a motor housing shell perfect for modding. He started by ripping the old engine and drivetrain out of the housing to make room for the BLDC motor and its driver. The motor was a project in itself; [Anton] rewound the original stator with much thicker wire and changed the coil configuration to milk as much torque as possible out of it. What started as a 180-kv motor ended up at 77 kv with much more copper and new Hall sensors for the controller. He also put a ton of effort into waterproofing the motor with epoxy resin. With a 3D-printed prop and a streamlined fairing, the new motor looks quite at home on the outboard. In fact, the whole thing barely looks customized at all — the speed control is even right on the tiller where you’d expect it.

The video below shows the build and a test run, plus an analysis of the problems encountered, chief of which is water intrusion. But as [Anton] rightly points out, that’s easily solved by reusing the original driveshaft and mounting the motor above the waterline, like this. Still, we like the look of this, and the idea of knocking around on the water nearly silently seems wonderful.

Continue reading “This Electric Outboard Conversion Makes For A Quiet Day On The Water” →

Wow! You Could Have A (Tiny) V8!

September 21, 2022 by 30 Comments

If you grew up before high gas prices and strict emission control regulations, you probably had — or wanted — a car with a V8 engine. An engineering masterpiece created in France, it would define automotive power for the best part of a century. Of course, you can still get them, but the realities of our day make them a luxury. [Vlad] shows us his latest Christmas list addition: a fully-functioning but tiny V8 — the Toyan FS-V800 that has a displacement of two centiliters.

It runs on R/C nitro fuel and is claimed to be the world’s smallest production V8. You can buy the thing built or as a kit and we suggest to protect your street cred, you claim you bought the kit even if you go for the assembled version. The cylinder bores are 17 mm and 16 tiny valves regulate the flow. There are even tiny mufflers for the manifold exhaust. [Dennis] has a video of his operating that you can see below, and his YouTube channel has a lot of information on building the kit and some modifications, too.

Cooling? Water-cooled, of course. The manufacturer claims the engine can rev to 12,500 RPM and can produce over four horsepower. The total size would allow it to fit easily in a five inch cubical volume. You could build it into something, or just display it as a conversation piece. Be prepared for sticker shock, though. We hear the going price for these is about $1,500.

If you’re a bit short on cash or would rather just play with some pretend ponies, this impressive open source engine simulator might be just what you’re looking for.

Continue reading “Wow! You Could Have A (Tiny) V8!” →

Young Inventor Builds Motor Without Rare Earths

August 12, 2022 by 49 Comments

[Robert Sansone] is a 17-year-old from Florida and, like most of us, he likes to tinker. He’s apparently got the time for it because he’s completed at least 60 projects ranging from animatronic hands to a high-speed go-kart. However, his interest in electric vehicles coupled with his understanding of the issues around them led him to investigate synchronous reluctance motors — motors that don’t depend on expensive rare earth magnets. His experiments have led to a novel form of motor that has greater torque than existing designs.

Rare earths are powerful but expensive, costing much more than common metals like copper or steel. Traditionally, synchronous reluctance motors use steel rotors and air gaps and exploit the difference in reluctance — a term for magnetic resistance– to generate rotation. [Robert’s] idea was to replace the air gap with a different material to increase the ratio of reluctance between the rotor and the gap. Reconfiguring the motor to a more traditional configuration shows startling results: the new design generated almost 40% more torque and did so more efficiently, as well.

His work has earned him first prize, and $75,000, in this year’s Regeneron International Science and Engineering Fair. It took 15 tries to get the motor to its current state, something made easier with 3D printing. There are plans for a 16th version that [Robert] hopes will perform even better. We can’t wait to see what he’ll do next.

Electric vehicles have made people look into many motor design topologies. The reluctance motor has been around for a long time, but controlling them has become significantly easier. That’s true of many kinds of motors.

Continue reading “Young Inventor Builds Motor Without Rare Earths” →

Atmospheric High-Voltage Motor Makes Useful Power

July 26, 2022 by 23 Comments

While it almost seems like an insane fever dream from an otherwise brilliant inventor, Nikola Tesla’s plan to harvest energy straight out of the atmosphere and essentially give it away is more reality than fiction. It’s usually prohibitively difficult get that energy out of the atmosphere for several obvious reasons, although it is still possible to do as [lasersaber] shows with his most recent atmospheric motor.

To help solve some of the logistical problems of harvesting electricity from the atmosphere, [lasersaber] is using a Van de Graaff generator as a stand-in for the high voltage gradient that can be found when suspending a long wire in the air. He has been experimenting with high-voltage motors like this for a while now and has refined his designs for corona discharge motors like these to be big enough and have enough torque to drive a drill bit. The motors have a conductive rotor with a series of discharge tubes on the stator, and exposing a metal point on the wiring (where the atmospheric wire would attach) to a sufficiently high voltage will cause rotation. In this case, it’s around 30,000 volts but with an extremely low current.

There are a number of videos documenting his latest build, including this follow-up video where he drills an arbitrarily large number of holes in various materials to demonstrate its effectiveness. Even though he is using a Van de Graaff generator in these builds, he does also show them working with a wire suspended by a drone as well for proof-of-concept. He’s also become somewhat of an expert on high-efficiency and low-power motors and has a number of other interesting builds based on these concepts.

Continue reading “Atmospheric High-Voltage Motor Makes Useful Power” →

Gym Equipment Converted To Generator

June 29, 2022 by 41 Comments

Energy cannot be created or destroyed, but the most likely eventual conclusion of changing it from one form or another will be relatively useless heat. For those that workout with certain gym equipment, the change from chemical energy to heat is direct and completely wasted for anything other than keeping in shape. [Oliver] wanted to add a step in the middle to recover some of this energy, though, and built some gym equipment with a built-in generator.

Right now he has started with the obvious exercise bike stand, which lends itself to being converted to a generator quite easily. It already had a fairly rudimentary motor-like apparatus in it in order to provide mechanical resistance, so at first glance it seems like simply adding some wires in the right spots would net some energy output. This didn’t turn out to be quite so easy, but after a couple of attempts [Oliver] was able to get a trickle of energy out to charge a phone, and with some more in-depth tinkering on the motor he finally was able to get a more usable amount of energy to even charge a laptop.

He estimates around 30 watts of power can be produced with this setup, which is not bad for a motor that was never designed for anything other than mechanical resistance. We look forward to seeing some other equipment converted to produce energy too, like a rowing machine or treadmill. Or, maybe take a different route and tie the exercise equipment into the Internet connection instead.