This Modded Shopping Cart Probably Isn’t Street Legal

If you don’t count the high center of gravity, the weight limit, the weak chassis, or the small size, a standard shopping cart is an almost ideal platform for building a fun drifting kart. At least, that was [Garage Avenger]’s thought process when he started this build to turn a shopping cart into the ultimate drift vehicle.

The first thing on the list was to solve the issues with the high center of gravity and the fact that he couldn’t fit in the cart easily. Chopping out the back of the basket as well as everything beneath it solved both of these problems. From there a custom chassis could be fabricated from square steel tubing which includes a lever system which controls the rake of the caster wheels and thus their driftability. The power train and battery system for this build comes from a 2400 W electric scooter with a few modifications made to get it to fit on the new chassis.

After a test drive of the original prototype, a few modifications were made including using smaller caster wheels in the back, the addition of a spring to make the lever action for the rear wheels easier to engage, some front casters for stability, and a seat a little more substantial than the metal mesh of the cart. With all the electronics put into the cart, he’s ready to drift off into the sunset. This isn’t his first crazy vehicle, either. When winter rolls around you’ll find him getting around in a jet-powered sled instead.

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Free And Open E-Reader From The Ground Up

Although ebooks and e-readers have a number of benefits over reading an analog paper book as well as on more common electronic devices like tablets, most of them are locked behind proprietary systems like Kindle which make it difficult to take control over your electronic library. While there are a few off-brand e-readers that allow users to take a bit of control back and manually manage their files and libraries, there are few options for open-source solutions. This project aims to provide not only a free and open e-reader from the hardware to the software, but also a server to host a library as well.

The goal of most of the build is to keep everything as FLOSS as possible including the hardware, which is based on a Raspberry Pi compute module. The display comes from Good Display, which includes a built-in light and a touchscreen. There’s a lithium battery to power the tablet-like device with a number of support chips to charge it, handle the display, and interface with the Pi. On the software side, the system uses MuPDF which has support for most ebook file types while the server side is based on Calibre and the Open Publication Distribution System.

A subsection of the build log discusses a lot of how the code works for those looking to build their own similar system based on this project. The project code is even hosted on GitLab, a more FLOSS-y version of GitHub. Free and open ebook readers have been a goal of a number of builders for some time now, as we’ve seen projects going back at least a few years now and others that hope to make the Kindle hardware a little more open instead.

Turning Horrible Browser Controls Into A Game

With all of the various keyboards, mouses (mice?), and other human interface devices (HID) available for our computers, there’s no possible way for developers to anticipate every type of input for every piece of software they build. Most of the time everything will work fine as long as some basic standards are kept, both from the hardware and software sides, but that’s not always the case. [Losso] noticed a truly terrible volume control method when visiting certain websites while also using a USB volume knob, and used this quirk to build a Breakout game with it.

It turns out his volume control knob would interact simultaneously with certain video players’ built-in volume control and the system volume for the operating system, leading to a number of undesirable conditions. However, the fact that this control is built in to certain browsers in the first place led to this being the foundation for the Breakout clone [Losso] is calling KNOB-OUT. Unlike volume buttons on something like a multimedia keyboard, the USB volume control knob can be configured much more easily to account for acceleration, making it more faithful to the original arcade version of the game. The game itself is coded in JavaScript with the source code available right in the browser.

If you’d like to play [Losso]’s game here’s a direct link to it although sometimes small web-based projects like these tend to experience some slowdown when they first get posted here. And, if you’re looking for some other games to play in a browser like it’s the mid-00s again, we’re fans of this project which brings the unofficial Zelda game Zelda Classic to our screens.

Docker-Powered Remote Gaming With Games On Whales

Cloud gaming services allow even relatively meager devices like set top boxes and cheap Chromebooks play the latest and greatest titles. It’s not perfect of course — latency is the number one issue as the player’s controller inputs need to be sent out to the server —  but if you’ve got a fast enough connection it’s better than nothing. Interested in experimenting with the tech on your own terms? The open source Games on Whales project is here to make that a reality.

As you might have guessed from the name, Games on Whales uses Linux and Docker as core components in its remote gaming system. With the software installed on a headless server, multiple users can create virtual desktop environments on the same machine, with each spawning as a separate process on the host computer. This means that all of the hardware of the host can be shared without needing to do anything complicated like setting up GPU pass-through. The main Docker container can spin up more containers as needed.

Of course there will obviously be limits to what any given hardware configuration will be able to support in terms of number of concurrent users and the demands of each stream. But for someone who wants to host a server for their friends or something even simpler like not having to put a powerful gaming PC in the living room, this is a real game-changer. For those not up to speed on Docker yet, we recently featured a guide on getting started with this powerful tool since it does take some practice to wrap one’s mind around at first.

Particle Physics On A Small, Affordable PCB

Experimenting in the world of particle physics probably brings to mind large, expensive pieces of equipment like particle accelerators, or at least exotic elements or isotopes that most of us can’t easily find. But plenty of common objects emit various particles, and it turns out that detecting these particles does not require government backing or acres of test equipment. In fact, you can get this job done with a few readily-available parts and [Tim] shows us how it’s done with his latest project.

The goal of his build is to have a working particle detector for less than $10 per board, although he’s making them in bulk to be used in an educational setting. The board uses a set of photodiodes enclosed in a protective PCB sandwich to detect beta particles from a Potassium-40 source. The high-energy electron interacts with the semiconductor in the photodiode and creates a measurable voltage pulse, which can be detected and recorded by the microcontroller on the board. For this build an RP2040 chip is being used, with a number of layers of amplification between it and the photodetector array used to get signals that the microcontroller can read.

Getting particle physics equipment into the hands of citizen scientists is becoming a lot more common thanks to builds like this which leverage the quirks of semiconductors to do something slightly outside their normal use case, and of course the people building them releasing their projects’ documentation on GitHub. We’ve also seen an interesting muon detector with a price tag of around $100 and an alpha particle detector which uses a copper wire with a high voltage to do its work.

Arduino PLC Keeps The Beat

For most of our prototype, hobby, or one-off electronics projects it’s perfectly fine to use a development platform like an Arduino Uno or something to that effect. They’re both easy to program and easy to wire up to projects without breaking the bank. But if you step into an industrial setting where reliability is paramount even in places that are noisy, vibrating all the time, hot, or otherwise unpleasant for electronics, you’ll want to reach for a programmable logic controller (PLC) that are much more robust. There is actually a PLC from Arduino, and if you want to dip your toes into the PLC world then take a look at this drum kit based on the Arduino Opta.

With the PLC at the core of the build, it’s on to making the drumming mechanisms themselves. For that, project creator [JC Audio] is using a series of solenoids attached to camera mounts with a custom 3D printed part that allows for quick assembly and disassembly so he can get the positioning of each drum sound just right. The high hat is taken care of by the noise of an internal solenoid, with the other drums striking various real drums and other solid objects in his shops. The solenoids themselves are driven by a solid-state relay expansion module to ensure there’s enough power

While the build doesn’t sit inside a factory and run for years at a time, a musician’s stage is certainly a rough enough environment that we might reach for a PLC over a standard development board for its benefits. The code for this project is available as well at the project’s GitHub page for those looking for a more advanced timekeeper to play along with their music practice, and for more details on why you might choose a PLC for your project take a look at this Arduino vs PLC showdown from a few years ago.

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Google Drive Now Bootable

USB drives are incredibly useful, both storing files for transport between different computers and for creating bootable drives that let us use or install other operating systems on our computers. While online file storage systems like Dropbox and Google Drive have taken over a large percentage of the former task from USB drives, they have not been able to act as bootable media, ensuring that each of us have a few jump drives lying around. That might not be the case anymore, though, as this guide is the first we know of to be able to use Google Drive to boot to a Linux system.

Unlike the tried-and-true jump drive methods, however, this process is not straightforward at all. It relies on two keys, the first of which is FUSE which allows a filesystem to be created in userspace. The second is exploiting a step in boot process of Linux systems where the kernel unpacks a temporary filesystem, called initramfs, in order to load the real filesystem. Normally a user doesn’t interact much with this step, but that doesn’t mean it’s impossible. A tool called dracut allows using an existing Linux installation to build a custom initramfs and in this case, the custom initramfs is built to include the proper support for both networking and FUSE.

The proof of concept in this demonstration originally ran in a container, using an existing project called google-drive-ocamlfuse to interact with Google Drive itself. From there, after sorting out some issues with root access, networking, malfunctioning symlinks, and various timeouts on the (perhaps predictably) slow system, the whole contraption was moved over to a laptop so it could be tested on real hardware. Everything runs, and although the original creator of this behemoth admits it is a bit “silly” they note that there may be some real-world use cases for something like this. We still won’t expect everyone to throw out their jump drives anytime soon, though. If you’re not feeling like your Linux skills are up to the challenge of something like this, we’d recommend you start with our own [Al Williams]’s Linux Fu series.