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Hackaday Links: May 12, 2019

May 12, 2019 by 27 Comments

The future of the musical instrument industry is in tiny, cheap, handheld synthesizers. They’re sold as ‘musical toys’. They bleep and bloop, and that’s about it. Korg may have just released the minimum viable product for this category, and thus the most popular product for this category. On the surface, the Korg Nu:Tekt doesn’t look like much, just a box with three knobs, a speaker, a (crappy) keyboard, and a few buttons. I/O includes MIDI in, Sync in and out, audio in, and headphones out. What’s inside is what counts. There’s a high-powered ARM core (STM32F446, a Cortex-M4 running at 180 MHz) and a ton of RAM. What’s the play here? It’s compatible with the Korg Prologue/Minilogue SDK, so you can put the same sounds from the flagship synthesizer on a tiny box that fits in your pocket. Things are starting to get weird, man. This is a toy, with the same sounds as the ‘pro’ level synth. Let it be known that the synth market is the most interesting segment of consumer electronics right now.

Bird, that ride share scooter startup, is now selling their scooters. It costs thirteen hundred dollars. Alternatively, you can pick some up for cheap at your city’s impound lot. Or for the low, low, price of free.

Razer, the company that makes garish computer peripherals aimed at ‘gamers’ and other people who are sucked deep into the existential turmoil of disempowerment, depression, and playing video games all day, are building a toaster. Gamers aren’t known for eating food that isn’t prepared by their mom, but the Razer consumer community has been clamoring for a professional gaming toaster since it was first teased on April Fool’s Day three years ago. You only eat so many cold Pop Tarts straight out of the box, I guess.

Everyone loves cupcake cars, and this year we’re in for a treat! We’re ringing the bell this weekend with the 6th annual Hackaday x Tindie meetup for the Bay Area Maker Faire. We got a few things going on here. Next Thursday we’ll be greeted with talks by The Only Makers That You Want To Meet. That’s HDDG, the monthly San Francisco meetup happening at the Supplyframe office, and it’s going to be packed to the gills this month. Don’t miss it. Next Saturday, we’re renting a bar close to the Faire. The 6th Annual Hackaday x Tindie MFBA Meetup w/ Kickstarter is usually at an Irish pub in San Mateo, but we’re getting a bigger venue this year. You’ll be able to move around in this venue.

Robot Hummingbird Imitates Nature

May 12, 2019 by 9 Comments

Purdue’s Bio-Robotics lab has been working on a robotic hummingbird and, as you can see in the videos below, have had a lot of success. What’s more, is they’ve shared that success on GitHub. If you want to make a flapping-winged robot, this is definitely where you start.

If you’ve ever watched a hummingbird, you know their flight capability is nothing short of spectacular. The Purdue robot flies in a similar fashion (although on a tether to get both power and control information) and relies on each wing having its own motor. The motors not only propel the wings but also act as sensors. For example, they can detect if a wing is damaged, has made contact with something, or has changed performance due to atmospheric conditions.

In addition to the tethered control system, the hummingbird requires a motion capture sensor external to itself and some machine learning. Researchers note that there is sufficient payload capacity to put batteries onboard and they would also need additional sensors to accomplish totally free flight. It is amazing when you realize that a real hummingbird manages all this with a little bitty brain.

The published code is in Python and is part of three presentations later this month at a technical conference (the IEEE International Conference on Robotics and Automation).  If you don’t want to wait on the paper, there’s a post on IEEE Spectrum about the robotic beast, available now and that article contains preprint versions of the papers. The Python code does require a bit to run, so expect a significant flight computer.

The last hummingbird bot we saw was a spy. We’ve also seen robots that were like bees — sort of.

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Bare Metal Programming With Only Three Buttons

May 12, 2019 by 28 Comments

For anyone who’s seen a 1970’s era microcomputer like the Altair 8800 doing its thing, you’ll know the centerpiece of these behemoths is the array of LEDs and toggle switches used as input and output. Sure, computers today are exponentially more capable, but there’s something undeniably satisfying about developing software with pen, paper, and the patience to key it all in.

If you’d like to get a taste of old school visceral programming, but aren’t quite ready to invest in a 40 year old computer, then [GClown25] might have the answer for you. He’s developed a pocket sized “computer” he’s calling the BIT4 that can be programmed with just three tactile switches. In reality it’s an ATMega4809 running C code, but it does give you an idea of how the machines of yesteryear were programmed.

In the video after the break, [GClown25] demonstrates the BIT4 by entering in a simple binary counter program. With a hand-written copy of the program to use as a reference, he steps through the memory addresses and enters in the command and then the value he wishes to operate on. After a few seconds of frantic button pushing, he puts the BIT4 into run mode and you can see the output on the array of LEDs along the top edge of the PCB.

All of the hardware and software is open source for anyone who’s interested in building their own copy, or perhaps just wants to take a peak at how [GClown25] re-imagined the classic microcomputer experience with modern technology. Conceptually, this project reminds us of the Digirule2, but we’ve got to admit the fact this version isn’t a foot long is pretty compelling.

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Modular CNC Build Gets You Both A Mill And A Laser Cutter

May 12, 2019 by 24 Comments

CNC builds come in all shapes and sizes. There’s delta manipulators, experimental polar rigs, and all manner of cartesian builds, large and small. After completing their first CNC build, [jtaggard] took what they learned and applied it in the development of a new machine.

It’s a desk-sized cartesian design, with a frame built from V-slot extrusion cut to size by circular saw. This is a great way to get quality extrusion for a custom build, and is readily available and easy to work with. The gantry rides on wheels, with the X and Y axes being belt driven, plus a screw drive for Z. A couple of NEMA 17s and a NEMA 23 provide motive power, and an Arduino Uno with stepper drivers is the brains of the operation. 1/4″ thick PLA plates are used to assemble everything, and while [jtaggard] intended to replace these with aluminium down the track, so far the plastic has proved plenty rigid enough for early tests of both machining and engraving wood.

It’s a great entry-level CNC build, which has proved usable with both a 500W spindle and a 2.5W laser for engraving. Being modular in nature, it would be easy to add other tools, such as a pen plotter or vinyl cutting blade for further versatility.

DIY CNC builds are always popular, as you end up with a useful tool as a reward for your hard work. Video after the break.

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Better Debating Through Electronics

May 12, 2019 by 8 Comments

Watch any news panel show these days, and you’ll see that things can very quickly become unruly. Guests compete for airtime by shouting over one another and attempting to derail their opponent’s talking points. [cutajar.sacha] had encountered this very problem in the workplace, and set about creating a solution.

The result is the Debatable Deliberator, and it combines the basics of “Talking Stick” practices with behavioural training through humiliation. Two participants each wear a headband, fitted with electronics. The holder of the magic ball may speak for as long as the timer counts down. If their opponent speaks during this time, their headband reprimands them with gentle slapping to the face. If the holder speaks over their assigned time, they are similarly treated to mechanical slapping.

It’s an amusing way to help police a discussion between two parties, and it’s all made possible with a trio of WeMos D1 ESP8266 boards. The headbands act as clients, while the ball acts as a server and keeps track of how many times each speaker has broken the rules.

WiFi projects such as this one have become much easier in the past few years with the wide availability of chips like the ESP8266. Of course, if you need more grunt, you can always upgrade to the ESP32.

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Mathics: How To Do Hard Math When You’re Not An MIT Janitor

May 11, 2019 by 27 Comments

Algebra is the bane of many a student, but it is surprisingly useful when it comes to electronics. Sure, you can just memorize all the permutations of things like Ohm’s law. But it is better if you can remember one form and deduce the others on the fly.

There are many occasions where you — as our old Algebra teacher used to say — need to use what you know to get what you don’t know. The gold standard, of course, is a computer program called Mathematica. For home and student use, the software is “only” about $160-$600, but commercial versions range from about $1,000 to nearly $8,000. Of course, there are free alternatives, and the one we’re looking at today is Mathics. It will run in your browser or as a desktop application powered by Python, and it’s available for free.

The program does a nice job of displaying mathematical formulae and you can get an idea of its power by visit the online version. which has examples if you click the question-mark in the upper right and look for the fourth item down. There’s also a standalone version of the online help.

We did have a little trouble with some of the gallery examples timing out, as well as the site certificate being expired. We also had a bit of difficulty remembering the linear algebra classes we took a long time ago! If you want something easy to play with try this:

Solve[4x+3==20,x]

Don’t forget to press Shift+Enter in the browser to get the solution.

Under the hood, MathJax and SymPy do a lot of the heavy lifting. In fact, we imagine a lot of the program’s intended audience would wind up using Jupyter notebooks with Python underneath. Of course, there are copies of Wolfram software on stock Raspberry Pi’s, too.