Teaching A DC Servo Motor To Act Like A Stepper

January 1, 2022 by Dave Rowntree 13 Comments

[Frank Herrmann] had an interesting idea to turn a geared DC motor into a servo motor assembly, but with a stepper motor-like interface. By stacking some small PCBs behind the motor body, it was possible to squeeze a DRV8837 DC motor driver and a pair of hall effect sensors on the first PCB layer, with the magnetic encoder nestled tightly behind it. Pin headers at the edge of the PCB connect to a second PCB bearing the microcontroller, which is based on the cheap STM32L432. The second PCB also holds an associated LDO and debug LED. Together, this handful of parts provide all that is needed to read the encoder, control the motor rotation and listen on the ‘stepper motor driver’ interface pins hooked up to the motion controller upstream. The Arduino source for this can be found on the project GitHub.

Whilst [Frank] mentions that this assembly has a weight and torque advantage over a NEMA 17 sized stepper motor, but we see no hard data on accuracy and repeatability which would be important for precise operations like 3D printing.

This project is part of a larger goal to make a complete 3D printer based around these ‘DC motor stepper motors’ which we will watch with interest.

While we’re on the subject of closed-loop control of DC motors, here’s another attempt to do the same, without the integration. If these are too small for you, then you always repurpose some windscreen washer motors.

Continue reading “Teaching A DC Servo Motor To Act Like A Stepper” →

NeoPixel Punk Console Drives WS2812s Using 555 Timers

January 1, 2022 by Robin Kearey 2 Comments

NeoPixels, a type of LED strip with individually addressable pixels, are a firm favorite among creators of intricate light effects. They are popular for their versatility and the ease with which you can daisy-chain them. Although the protocol to drive these little LEDs can be rather tricky to implement due to tight signal timing constraints.

However, [Adrian Studer] proved that driving WS2812-based LED strips like the NeoPixel series doesn’t necessarily require hand-optimized assembly code. In fact, it doesn’t require any code at all. He built the NeoPixel Punk Console, a device that creates a light show without even using a microcontroller. Just a handful of 555 timers and some 74HC series logic work together to produce pulses with approximately correct timings.

Operating the device is as easy as tweaking a few potentiometers, just like its namesake the Atari Punk Console. It’s quite a random process though, and it might be impossible to re-create a pattern that you liked. Also, the LEDs mostly light up in primary colors at full power, though [Adrian] plans to make an improved version that drives the red, green, and blue subpixels separately. But the fact that all of this is implemented by just a bunch of 555 timers makes it a rather impressive hack by any standard.

We’ve seen more than a few ways of driving NeoPixels or similar WS2812-based LED strips, though all of them use a microprocessor of some sort; you can fire up a classic 6502, use SPI and DMA on a PIC32, or just plug in a single ARM Cortex M0+.

Continue reading “NeoPixel Punk Console Drives WS2812s Using 555 Timers” →

Ski Lift Design Does The Impossible

January 1, 2022 by Ryan Flowers 21 Comments

Tis The Season, for those who are so inclined, to loft themselves to the top of a steep snow-covered hill and then go downhill, really fast. And if something gets in their way, turn. Whether they be on skis, a snowboard, or some other means, getting down usually involves using gravity. Getting up, on the other hand, usually involves a ski lift. And in the video by [kalsan15] after the break, we learn how technology has stepped in to make even the most inaccessible slopes just a lift ride away.

In its most simple form, a ski lift is two pulleys connected by a steel cable. The pulley at the bottom of the hill is powered, and the pulley at the top of the hill serves as an idler. Attached to the steel cable are some means for a person to either sit down or grab a handle and be hoisted to the top of the hill.

Such a simple arrangement works fine if the geography allows for it, but what if there are turns, or there need to be multiple idlers to keep the wire taut but also close to the ground? Again, the most basic ski lifts have limitations. If the cable turns left around the idler, then the attachment for the handle or chair has to be on the right, making a right turn around the idler an impossibility.

How then can this problem be solved? We won’t spoil the outcome, but we recommend checking out [kalsan15]’s video for an excellent description of the problem and the solution that’ll leave you wondering “Why didn’t I think of that!?”

If you don’t find this hacky enough, then take a moment to learn how you too can not just make a gas-powered ski lift for your cabin in the woods, but then ride your slope down on your DIY Ski Bike!

Continue reading “Ski Lift Design Does The Impossible” →

This film projecter is hiding an Arduino Uno that controls a water-based cooling system.

Cool The Shop With A Thermal Battery-Based System

January 1, 2022 by Kristina Panos 64 Comments

Having any kind of shop is pretty great, no matter how large it may be or where it’s located. If the shop is in an outbuilding, you get to make more noise. On the other hand, it will probably get pretty darn hot in the summer without some kind of cooling system, especially if you don’t have a window for a breeze (or a window A/C unit).

[Curtis in Seattle] built an awesome thermal battery-based cooling system for his shop. The battery part consists of five 55-gallon drums full of tap water that are connected in series and buried a foot underground, about two feet out from the wall. There are two radiators filled with water and strapped to 20″ box fans — one inside the shop, which sends heat from the shop into the water, and another outside that transfers heat out of the water and into the cool night air. Most summer days, the 800-square-foot shop stays at a cool 71°F (21.7°C).

We love that the controls are housed in an old film projector. Inside there’s an Arduino Uno running the show and taking input from four DS18B20 one-wire temperature sensors for measuring indoor, outdoor, battery, and ground temperatures. There are four modes accessible through the LCD menu — idle, cool the shop, recharge mode, and a freeze mode in case the outside temperature plummets. Why didn’t [Curtis in Seattle] use anti-freeze? It’s too expensive, plus it doesn’t usually get that cold. (Although we hear that Seattle got several inches of snow for Christmas.) Check it out after the break.

If you can’t just go burying a bunch of 55-gallon drums in the ground where you live, consider building a swamp cooler out of LEGO.

Continue reading “Cool The Shop With A Thermal Battery-Based System” →

Genius Or Cursed, This USB-C Connector Is Flexible

January 1, 2022 by Jenny List 18 Comments

USB connectors have lent themselves to creative interpretations of their mechanical specifications ever since the first experimenter made a PCB fit into a USB-A socket. The USB-C standard with its smaller connector has so far mostly escaped this trend, though this might be about to change thanks to the work of [Sam Ettinger]. His own description of his USB-C connector using a flexible PCB and a BGA-packaged ATTiny84A microcontroller is “cursed”, but we can’t decide whether or not it should also be called “genius”.

Key to this inspired piece of connector fabrication is the realization that the thickness of BGA and flex PCB together comes to the required 0.7 mm. The BGA provides the necessary stiffness, and though it’s a one-sided connector it fits the space perfectly. There are several demo boards as proofs-of-concept, and the whole lot can be found in a GitHub repository.

We can see this technique finding a use in all kinds of diminutive USB-C projects, however cursed or genius it may be. We like to see projects that push the edges of what can be done with the medium, with a nod to a previous cursed USB-C device.

Continue reading “Genius Or Cursed, This USB-C Connector Is Flexible” →

Blackberry Will Run Out Of Juice On January 4th

January 1, 2022 by Kristina Panos 47 Comments

Happy New Year, though it may not be for Blackberry fans. The company that has so often had their products compared to a certain addictive substance recently announced that they are ending support for Blackberry OS and Blackberry 10 devices.

What does this mean? While they won’t be bricking phones outright, they might as well be. On January 4th, Blackberry will be shutting off all the key services — data, SMS, phone calls, and 911 support. In official terms, they are ending network provisioning for these older devices, meaning that they won’t be able to join any cellular or WiFi networks.

Unless you’re old enough to remember, it may seem strange that these half-screen, half-keyboard machines once dominated the mobile market. But back then, the people who used them were texting wizards who had broken free from the chains of the T9 keyboard.

Though this news may not mean much except to a select few, it’s still sad to see the Blackberry era come to a true end. We never had one ourselves during the heyday, though we did pick up a cheap used model to carry around as a tiny mobile writing device and calendar. We sure do miss phones with real keyboards though, and would love to see them come back. At least the keyboards themselves get love in the hacker community.

[Main and thumbnail images via Digital Trends]

Virtual Eurorack Based CPU Computes To The Beat Of A Different Drum Module

January 1, 2022 by Ryan Flowers 3 Comments

In Arthur C. Clarke’s 1972 story “Dial F for Frankenstein”, the worlds first global network of phone exchanges was created by satellite link, and events happened that caused the characters in the story to wonder if the interconnected mesh of machinery had somehow become sentient. And that’s what we wondered when we saw this latest virtual CPU construction built by GitHub user [katef] and made from a virtual analog synthesizer software called VCV Rack.

Analogous to a Redstone computer in Minecraft, there’s no physical hardware involved. But instead of making crazy synth sounds for a music project, [katef] has built a functioning CPU complete with an Arithmetic Logic Unit, an adder, and other various things you’ll find in a real CPU such as registers and a clock.

While no mention is made of whether the construct is sentient, [katef] fully documented the build on their GitHub page, and so go check that out for animated pictures, links to more information, and more. It’s quite impressive, if not just a little bonkers. But most good hacks are, right?

We love unique CPU builds, and you might get a kick out of this one made from- that’s right- 555 timers. Thanks to [Myself] on the Hackaday Discord server for the tip, and be sure to send in your favorite outrageous projects to the Hackaday tip line!