It’s not a question you ask yourself every day, but it’s one that the [Brick Experiment Channel] set out to answer: how fast can you spin a LEGO wheel by hand? In their typical way, they set about building an increasingly complex contraption to optimize for the very specific case of maximum RPM.
The build starts with a LEGO wheel fitted to an axle, supported in two LEGO Technic beams. A white flash mark is also attached onto a part of the axle for measuring the rotational speed with a photo-tachometer. A first attempt gets as fast as 1,700 RPM. Upgrades come thick and fast , and with a three-stage compound geartrain, the handcranked wheel reaches 6,300 RPM. Adding a further stage introduces the problem that the plastic Technic axle begins to twist under the torque input by the hand.
Taking a new approach of pulling on a string to turn the wheel, the first attempt nets 8,300 RPM. Gearing pushes this further to 12,900 revs, but adding more gears again leads to the problem of axles bending under the strain. A bidirectional rope pull design helps, though, and the system reaches 13,100 RPM.
Some of the parts have been damaged thus far, but a rebuild with fresh parts that are nicely lubricated provides a huge boost. The now-slippery shafts run smoother and the wheel hits a blistering 19,300 RPM as the mechanism disassembles itself.
It’s a less complex pursuit than some earlier works from [Brick Experiment Channel], like the impressive pole climbing designs we’ve seen previously. However, it’s a video that shows the power of iterative design and the gains possible from that process.
Continue reading “How Fast Can You Spin A LEGO Wheel By Hand?”
One of the biggest reasons for playing older video games on original hardware is that emulators and modern controllers can’t replicate the exact feel of how those games would have been originally experienced. This is true of old PC games as well, so if you want to use your original Sidewinder steering wheel or antique Logitech joystick, you’ll need something like [Necroware]’s GamePort adapter to get them to communicate with modern hardware.
In a time before USB was the standard, the way to connect controllers to PCs was through the GamePort, typically found on the sound card. This has long since disappeared from modern controllers, so the USB interface [Necroware] built relies on an Arduino to do the translating. Specifically, the adapter is designed as a generic adapter for several different analog joysticks, and a series of DIP switches on the adapter select the appropriate mode. Check it out in the video after the break. The adapter is also capable of automatically calibrating the joysticks, which is necessary as the passive components in the controllers often don’t behave the same way now as they did when they were new.
Plenty of us have joysticks and steering wheels from this era stored away somewhere, so if you want to experience Flight Simulator 5.0 like it would have been experienced in 1993, all it takes is an Arduino. And, if you want to run these programs on bare metal rather than in an emulator, it is actually possible to build a new Intel 486 gaming PC, which operates almost exactly like a PC from the 90s would have.
Continue reading “Retro Gaming With Retro Joysticks”
Sometimes there is pleasure in watching an expert demonstrating his craft, particularly so when the craft is unusual or disappearing. A video came our way of just such a thing, and it’s of a craft so rare that it’s possible few of us will have considered it. We’re used to buying tyres for our motor vehicles that come pre-made in a mould for the size of our wheels, but how many of us have considered where the origins of the rubber tyre lie? How did a 19th-century horse-drawn buggy get its tyres? [EngelsCoachShop] take us through the process, putting rubber on a set of wooden carriage wheels.
These wheels would originally have had iron rims, that must have provided a jarring ride on cobbled roads of the day. English coach-builders of the mid 19th century were the first to fit solid rubber tyres, and it’s this type of tyre that’s being fitted in the video. Instead of the rubber ring we might expect the tyre is cut from a length of vulcanised rubber extrusion with a significant overlap, then a pair of high-tensile wires are fed through holes in the extrusion. The impressive part is the jig for creating the tyre, in which the rubber is compressed to a tight fit on the wheel before the wires are cut and their ends brazed together. Once the wheel is released from the jig the compressed tyre expands to the point at which its ends meet, making a perfect circular tyre held tightly on the rim. Few of us will ever see this for real, but we’re privileged to see it on the screen.
We may not deal with wooden wheels very often, but this isn’t the first set we’ve seen.
Continue reading “Rubber Tyres Before There Were Tyres”
For a while now, Mac Pro towers have had the nickname “cheese grater” because of their superficial resemblance to this kitchen appliance. Apple has only been a company since the 70s, though, and is much newer than one of its historic rivals, IBM. In fact, IBM is old enough to have made actual cheese-related computers as far back as the 1910s, and [Hand Tool Rescue] recently obtained one of these antique machines for a complete restoration.
The tool arrived to the restoration workshop in a state so poor that it was difficult to tell what many of the parts on the machine did except for the large cleaver at the top. The build starts with a teardown to its individual parts, cleaning and restoring them to their original luster, machining new ones where needed, and then putting it all back together. The real mystery of this build was what the levers on the underside of the machine were supposed to do, but after the refurbishment it was discovered that these are the way that portions the cheese wheel would be accurately sized and priced before a cut was made.
By placing a section of a wheel of cheese on the machine and inputting its original weight with one of the levers, the second lever is adjusted to the weight of cheese that the customer requested, which rotates the wheel of cheese to the correct position before a cut is made. To us who are spoiled with a world full of electronic devices, a mechanical computer like this seems almost magical, especially with how accurate it is, but if your business in the 1910s involved cheese, this would have been quite normal. In fact, it would be 50 more years before IBM created the machines that they’re more commonly known for.
Thanks to [Jasper Jans] for the tip!
Continue reading “IBM Cheese Cutter Restoration”
Wheels are all well and good for getting around, but they only tend to rotate about a single axis. Omni-wheels exist, but they’re still a little too pedestrian for [James Bruton]. His latest project involved 3D printing custom omni-balls which roll in all directions. (Video, embedded below.)
The omniball concept comes from earlier work by Osaka University, which also produced a treaded tank-like vehicle by the name OmniCrawler as well. The spherical design, fitted with an axle and casters as well, allows rotation in multiple directions, allowing for a platform fitted with such omni-balls to easily rotate and translate in all directions.
[James] set about creating his own version of the design, which relies on grippy TPU filament for grip pads to give the 3D printed hemispheres some much needed grip. There’s also bearings inside to allow for the relative rotation between the hemispheres and the internal castor, necessary to allow the wheels to move smoothly when sitting on either pole of the hemispheres. Skate bearings were then used to assemble three of the omni-balls onto a single platform, which demonstrated the ability of the balls to roll smoothly in all directions.
While it’s just a demonstration of the basic idea for now, we can imagine these balls being used to great effect for a robot platform that needs to navigate in tight spaces on smooth surfaces with ease. The mechanical complexity of the omni-balls probably negates their effective use in dirtier offroad contexts, however.
We’ve seen [James]’s work before too – such as his compliant leg design for walking robots, and his active gyroscope balancer last week. When does [James] sleep?
Continue reading “3D Printing Omni-Balls For Robot Locomotion”
Hamsters are great pets, especially for those with limited space or other resources. They are fun playful animals that are fairly easy to keep, and are entertaining to boot. [Kim]’s hamster, [Mr. Fluffbutt], certainly fits this mold as well but [Kim] wanted something a little beyond the confines of the habitat and exercise wheel and decided to send him on a virtual journey every time he goes for a run.
The virtual hamster journey is built on an ESP32 microcontroller which monitors the revolutions of the hamster wheel via a hall effect sensor and magnet. It then extrapolates the distance the hamster has run and sends the data to a Raspberry Pi which hosts a MQTT and Node.js server. From there, it maps out an equivalent route according to a predefined GPX route and updates that information live. The hamster follows the route, in effect, every time it runs on the wheel. [Mr Fluffbutt] has made it from the Netherlands to southeastern Germany so far, well on his way to his ancestral home of Syria.
This project is a great way to add a sort of augmented reality to a pet hamster, in a similar way that we’ve seen self-driving fish tanks. Adding a Google Streetview monitor to the hamster habitat would be an interesting addition as well, but for now we’re satisfied seeing the incredible journey that [Mr Fluffbutt] has been on so far.
When we talk about wheels, the vast majority of the time we’re talking about ho-hum cylindrical rollers as seen on all manner of human conveyances. However, there are all manner of wild and wacky shapes that roll, and having had some experience with them, [Maker’s Muse] decided to take a shot at having a robot drive on them. (Video, embedded below.)
The benefit of a 3D printer is that it makes producing these parts with strange geometries a cinch. The video shows a variety of designs, from the wobbly “Nightshades” to the entertaining “Prongle” wheels being put through a variety of tests. In an attempt to equalise the playing field, each design was matched in its surface area so as not to artificially bias the results.
While the wobbly designs look strange, they also come with some benefits over simple disc wheels, providing extra traction on both carpet and sand. Particularly impressive was the performance of the 8-spoke wheels on the beach, though as this design mimics real-world sand tyres, we’re not surprised at the results. We’ve seen similar 3D printed parts do the job for driving on water, too.
Continue reading “3D Printed Wobbly Wheels Put Through Their Paces”