The drive train of this bicycle starts with a brushless DC motor from a washing machine. It has been slightly modified to run on 48 volts, and is installed inside the triangle of the bike’s frame. It has a chain driving the bike’s crank, retaining the original chain and gearing setup (unlike many electric bike hacks that utilize hub motors). The crank has also been specially modified to include a freewheel, a necessary feature so that the motor can operate without spinning the pedals. Everything except the motor has been custom fabricated including the mounts and the electronics.
[jimminecraftguy] reports speeds of 110 kph which is a little crazy for a 20-year-old aluminum frame bike, and we’d guess it’s not street legal in many jurisdictions, but we can’t really find much fault with this build in general based on the amount of innovation required to get this working at all. A few more improvements for the build are in the works, including improved batteries and a cover for the sides to keep the local law enforcement from getting too suspicious. We can’t wait to see the final version. Continue reading “The Spin Cycle: Washing Machine Motor Converts 10-Speed To E-Bike”→
There are a surprising wealth of parts inside of old laptops that can be easily scavenged, but often these proprietary tidbits of electronics will need a substantial amount of work to make them useful again. Obviously things such as hard drives and memory can easily be used again, but it’s also possible to get things like screens or batteries to work with other devices with some effort. Now, there’s also a way to reuse the trackpad as well.
This build uses a PS/2 touchpad with a Synaptics chip in it, which integrates pretty smoothly with an Arduino after a few pins on the touchpad are soldered to. Most of the work is done on the touchpad’s built in chip, so once the Arduino receives the input from the touchpad it’s free to do virtually anything with it. In this case, [Kushagra] used it to operate a stepper motor in a few different implementations.
If you have this type of touchpad lying around, all of the code and schematics to make it useful again are available on the project page. An old laptop in the parts bin is sure to have a lot of uses even after you take the screen off, but don’t forget that your old beige PS/2 mouse from 1995 is sure to have some uses like this as well.
It used to be a staple of junior high physics class to build some sort of motor with paperclips or wire. A coil creates a magnetic field that makes the rotor move. In the process of moving, brushes that connect the coil to the rest of the circuit will reverse its polarity and change the magnetic field to keep the rotor turning. However, brushless motors work differently. The change in magnetic field comes from the drive controller, not from brushes. If you want to build that model, [Rishit] has you covered. You can see his 3D printed model brushless motor running in the video below.
Usually, you have a microcontroller determining how to drive the electromagnets. However, this model is simpler than that. There are two permanent magnets mounted to the shaft. One magnet closes a reed switch to energize the coil and the other magnet is in position for the coil to attract it, breaking the current. As the shaft turns, eventually the second magnet will trip the reed switch, and the coil will attract the first magnet. This process repeats over and over.
We all have old projects which maybe didn’t quite deliver knocking about, sometimes they gather dust for years. They have a use though, in that when you *really* need that part you can lift it from that forgotten project. That’s what [Mustie1] did with a forgotten electric bicycle project, he took its motor and used it to automate his bead roller.
A bead roller is a tool used in the world of automotive bodywork to press a bead — a continuous depression — into a piece of sheet metal. The inexpensive roller he had fitted in a bench vice, and was operated by means of a handle. Unfortunately the size of the tool meant that it was difficult to operate at the same time as rolling a precise bead, so improvement was required.
He first considered using a cordless drill, but then remembered the electric bicycle project. Its geared motor had come from an electric wheelchair and certainly possessed the right speed, but he needed a suitable sprocket. This was supplied from a scrap engine-assisted bicycle that he’d acquired, and proved to be perfect for the job. The final automated roller used the trigger controller from a cordless drill mounted in a foot switch, and the roller mounted on a stand repurposed from a piece of gym equipment. The result is a useful, and above all controllable, tool that can run a perfect bead in any shape desired on a piece of sheet metal.
The humble automotive alternator hides an interesting secret. Known as the part that converts power from internal combustion into the electricity needed to run everything else, they can also themselves be used as an electric motor.
These devices almost always take the form of a 3-phase alternator with the magnetic component supplied by an electromagnet on the rotor, and come with a rectifier and regulator pack to convert the higher AC voltage to 12V for the car electrical systems. Internally they have three connections to the stator coils which appear to be universally wired in a delta configuration, and a pair of connections to a set of brushes supplying the rotor coils through a set of slip rings. They have a surprisingly high capacity, and estimates put their capabilities as motors in the several horsepower. Best of all they are readily available second-hand and also surprisingly cheap, the Ford Focus unit shown here came from an eBay car breaker and cost only £15 (about $20).
We already hear you shouting “Why?!” at your magical internet device as you read this. Let’s jump into that.
Messing about in boats has always held a curious appeal for the hardware hacker. Perhaps that’s because it remains an approachable way to make something that moves under its own power with a bit of speed, and barring calamities, the worst that can happen to the unwary boater is a soaking. [NASAT Channel] is a Vietnamese hacker who is a serial producer of small motorised boats, and one of his latest is a particularly impressive example.
The boat itself is a relatively conventional expanded polystyrene hull covered with fiberglass, but the motive power is something a little special. He’s taken eight of the ubiquitous 775 DC brushed motors and used them in a star configuration with beveled gears, which in turn drives a flexible shaft which goes straight to a propeller under the craft. Each motor shares a water cooling pipe serviced by a small pump, and the drive comes from a pair of cheap PWM motor controllers. We see him zipping up and down a stretch of river next to some moored boats, and if we’re honest, we wouldn’t mind a go ourselves.
We’re not entirely convinced such a rough-and-ready eight-way gearbox will be reliable for long-term use, and we’d be interested to know just how equally so many motors are actually sharing the load. But we like it for its sheer audacity, and we think you will too. Take a look at the video below the break, and if you’re inspired then grab a hammock, some friends, and have a go.
Radio control projects used to be made of materials such as metal or wood, and involve lots of hand crafted parts. That’s still one way to go about things, but 3D printing has become a popular tool in recent years. [RCLifeOn] has been working on a 3D printed jet boat, which recently got a serious power upgrade.
The boat in question received a 5000W brushless motor – significant power for a vehicle weighing less than 2kg. Powered by a 12S lithium pack, and outfitted with a water jacket for cooling, it drives the boat through an off-the-shelf turbine after initial attempts to DIY the drivetrain were unsuccessful.
The biggest problem in the project came from coupling the motor to the turbine. A 3D printed coupler was unable to hold up to the strain, while attempts to make a metal part failed due to the lack of a lathe. Eventually the solution was found by daisy chaining two off-the-shelf parts together.
The boat proved itself ably on the water, with the large motor proving more than capable of shifting the boat at a strong clip. It’s an excellent shakedown for the parts that will eventually find themselves in a powered surfboard build. We’ve seen [RCLifeOn]’s work before, too, like these stylish 3D printed sneakers. Video after the break.