Author: Matthew Carlson

289 Articles

Remoticon 2021 // Hash Salehi Outsmarts His Smart Meter

January 13, 2022 by 27 Comments

Smart meters form mesh networks among themselves and transmit your usage data all around. Some of them even allow the power company to turn off your power remotely, through the mesh. You might want to know if any of this information is sensitive, or if the power shutdown system has got glaring security flaws and random people could just turn your house off. Hash Salehi has set out to get inside these meters, and luckily for the rest of us, he was kind enough to share his findings during Remoticon 2021. It’s a journey filled with wonderful tidbits about GNU Radio, embedded devices, and running your own power company inside a Faraday cage.

The smart meter in question is deployed by a power company known as Oncor in the Dallas, Texas, area. These particular meters form an extensive mesh network using a ZigBee module onboard that allows them to to pass messages amongst themselves that eventually make their way to a collector or aggregator to be uploaded to a more central location. Hash obtained his parts via everyone’s favorite online auction house and was surprised to see how many parts were available. Then, with parts in hand, he began all the usual reverse engineering tricks: SDR, Faraday cages, flash chip readers, and recreating the schematic. Continue reading “Remoticon 2021 // Hash Salehi Outsmarts His Smart Meter” →

suspended carbon nanotube

Falling Down The Carbon Rabbit Hole

January 11, 2022 by 18 Comments

Research projects have a funny way of getting blown out of proportion by the non-experts, over-promising the often relatively small success that the dedicated folks doing the science have managed to eke out. Scaling-up cost-effectively is one of the biggest killers for commercializing research, which is why recent developments in creating carbon nanotube transistors have us hopeful.

Currently, most cutting-edge processes use FETs (Field Effect Transistors). As they’ve gotten smaller, we’ve added fins and other tricks to get around the fact that things get weird when they’re small. The industry is looking to move to GAAFETs (Gate All Around FET) as Intel and Samsung have declared their 3 nm processes (or equivalent) will use the new type of gate. As transistors have shrunk, the “off-state” leakage current has grown. GAAFETs are multi-gate devices, allowing better control of that leakage, among other things.

As usual, we’re already looking at what is past 3 nm towards 2 nm, and the concern is that GAAFET won’t scale past 3 nm. Carbon Nanotubes are an up-and-coming technology as they offer a few critical advantages. They conduct heat exceptionally well, exhibit higher transconductance, and conduct large amounts of power. In addition, they show higher electron mobility than conventional MOSFETs and often outperform them with less power even while being at larger sizes. This is all to say that they’re an awesome piece of tech with a few caveats. Continue reading “Falling Down The Carbon Rabbit Hole” →

Joel in his minecart

This Little Minecraft Mine Cart Of Mine

January 10, 2022 by 8 Comments

[Joel] of Joel Creates loves trains and Minecraft. So what better way to combine them than to make a real-life electric mine cart and ride it around?

At first glance, it seems pretty straightforward. Four wheels, each with a flange, mounted to a box with a motor. In practice, it was a little more complex than that. Just finding a spot of track to even ride on is tricky. Most “abandoned” tracks that you might see around your city often aren’t all that abandoned. Luckily for [Joel], he remembered an amusement park in the area that he went to as a kid, which he remembered having a decent amount of track. Additionally, the rails were smaller and closer to the scale of a real Minecraft track where one block is 1 meter. After calling up the owner and receiving permission, Joel began to build his cart.

First attempts to procure actual train wheels were foiled by cost and lead times, and simply CNCing a set of wheels was too expensive from a time and materials point of view. [Joel]’s first thought was about making an assembly out of two wheels to grip the rail, much like a roller coaster. However, there were dozens of switch points on the track at the park and several road crossings, both things that wouldn’t work with that sort of setup. Stumbling upon a bit of hacker inspiration, [Joel] turned to brake drums, which happen to be reasonably close to the correct size. They also have the superb quality of being relatively cheap and available. Almost all the parts were CNCed out of aluminum, plywood, or foam.

Given that the theme of the build was doing things to scale, [Joel] was mindful of the top speed of a minecart in the game, which is 8 meters per second or roughly 25 miles per hour, so he set that as his goal to hit. A beefy motor from an online warehouse and a lithium-ion pack allowed him to hit that easily; it was just a matter of doing so safely.

If you need even more Minecraft vehicles in your life, perhaps an RC boat might do the trick? Video after the break.

Continue reading “This Little Minecraft Mine Cart Of Mine” →

Portable PI Powered Music Player

January 9, 2022 by 14 Comments

There was a brief time in the early 2000s when we carried cellphones, wallets, keys, and a bespoke digital media player loaded with a small selection of our music libraries. Devices like iPods, Zunes, Sandisk Sansa, and iRiver. Then as cell phones gained more storage and processing power, the two devices became one, and audio players slipped to obscurity as sports accessories. Perhaps in that vein, [BalderDragonSlayer] made his own Raspberry Pi-powered media player.

The device was cobbled together using a Raspberry Pi Zero, an Adafruit OLED bonnet, a LiPo charger, and a cheap USB DAC. The interface software is written in python, which has all your usual player controls, using the directional joystick and two pushbuttons on the bonnet. DietPi is a slimmed-down Linux that offers an impressively fast boot time, which is why it was picked for this project. The case was a simple project case with some holes dremeled into the face for the screen and buttons.

It is a wonderful little project that seems wonderful for walks in the park. This isn’t the first Pi-powered media player we’ve seen before. But we’re hoping we see more in the future.

A Gorgeous Desk With AMD Inside

January 4, 2022 by 7 Comments

We’re the first to admit that we don’t see much woodworking here at Hackaday. But this desk with a PC inside from [John Heisz] is just too gorgeous not to share.

The build is mostly cherry veneered half-inch plywood and real cherry. There are dozens of angles and complex pieces that all fit together in a valuable and powerful desk. The centerpiece of the desk is the air intake grill with a 2019 Apple Mac Pro-like finish. [John] mentions that he previously did it by hand with just a parked drill bit and some patience, but he vastly prefers the automated way. Two cubbies flank the center vent, made from plywood with cherry veneers glued on. A USB hub is hidden at the back in one of the cubbies, exposing all the I/O for the AMD-powered desktop PC hidden inside. The top of the desk is hinged to allow easy access to the PC. [John] asserts that he made the coolest desk in the known universe. We don’t know if we can say it’s the coolest, but we certainly appreciate the process and expertise that made it.

After you’ve finished your new desk build inspired by [John]’s project, perhaps you might be interested in a levitating turbine desk toy to seal the deal. Video after the break.

Continue reading “A Gorgeous Desk With AMD Inside” →

Peering Into The Murky Depths Of Alder Lake

December 29, 2021 by 17 Comments

The winds of change are in the air for CPUs. Intel has long lorded over the computing world, and they remain a force to contend with, but many challengers gather at their gates. AMD, ARM, IBM, and other X86 designs sense a moment of weakness. In response, Intel released their Alder Lake platform with high-performance and high-efficiency cores, known as Golden Cove and Gracemont, respectively. [Clamchowder] and [cheese] have written up as many details as they were able to suss out about Gracemont.

ARM has done a multi-multi core design (big.LITTLE) for several years where they have a mix of high-power, high-performance cores and smaller, low-power cores. This allows the scheduler to make tradeoffs between power and performance. Typically the smaller cores in an ARM design are simpler in-order processors, having more in common with a microcontroller than with a full-scale desktop core. Many people have made an obvious comparison with the apparent similarities between ARM’s approach and Intel’s new offerings as Gracemont is based on Intel’s old Atom core, a low-power single issue, in-order processor. Continue reading “Peering Into The Murky Depths Of Alder Lake” →

a home depot surfboard

Foam Surfboard From Scratch

December 29, 2021 by 5 Comments

Have you ever wanted to make your own surfboard, but felt held back by a lack of tools, materials, or the cost of it? Drawing almost entirely from what can be found at a well-known home improvement retailer, [AndrewW1997] details the steps needed to craft your board.

In his guide, he details the difference between XPS (expanded polystyrene) and EPS (extruded polystyrene) and how each product’s closed cell and open cell nature affects the final board. Starting with two pink sheets of XPS, he laminated them together with glue to form his blank. A stringer is a long piece of wood in the middle of the surfboard that provides additional flex and strength. Some flooring plywood curved with a jigsaw provides the shape needed. Unfortunately, the blank needs to be split in half to install the stringer. However, he has a trick for gluing the blank back together without it buckling, and that trick is ratchet straps.

He cuts the foam into roughly the right shape with a hot wire. Clean up is done with sanding blocks, a plane, and a level. The next step is laminating the board with epoxy and fiberglass. Next, [Andrew] details a few considerations around the process and gets to glassing. Sanding up to 2000 grit and some polishing compound make the board gorgeous. After a bit of final curing time, you’re ready to ride some waves.

There’s a handy playlist on YouTube detailing the process so you can follow along. Once you’ve finished your surfboard, perhaps your next project will be to power it up with a jet drive. Video after the break.

Continue reading “Foam Surfboard From Scratch” →