Hackaday Links: December 3, 2017

Remember the Psion? Back when PDAs were a thing, the Psion was the best you could get. It was, effectively, a palm-top computer with a real qwerty keyboard. It didn’t have Bluetooth, it couldn’t browse the web, and it didn’t have WiFi, but this was an AA-powered productivity machine that could fit in your pocket. Now there’s a new palmtop from Psion engineers. The Gemini PDA is basically a smartphone with a real keyboard that runs Ubuntu. It’s also has a smaller battery than other devices with this form factor, meaning the TSA thinks it’s a smartphone. This thing is going to be cool.

TechShop, Inc. has reached an agreement to sell the company to TechShop 2.0, LLC. New ownership seeks to re-open, continue running makerspaces. Details coming soon.

Arcade monitors are cool, and vector monitors are even cooler. [Arcade Jason] created a gigantic 36″ vector monitor. It’s thirty-six inches of Gravitar, in all its vector glory.

A few links posts ago, I pointed out someone was selling really awesome, really cheap LED panels on eBay. I got my ten panels, and [Ian Hanschen] bought sixty or some other absurd amount. Now, these panels are going for $300 for a 10-pack instead of $50. Sorry about that. Nevertheless, the reverse engineering adventure is still ongoing, and eventually, someone is going to play Mario on these things.

The ESP32 is finding its way into all sorts of consumer electronics. Check this thing out. It’s an ESP32, four buttons, and a circular display. If you want to make your own Nest thermostat, or anything else that needs an awesome circular display, there you go.

Speaking of circular displays, are there any non-CRT displays that come with a polar coordinate system? Every circular LCD or OLED I’ve ever seen uses a Cartesian system, which doesn’t really make sense when you can’t see 30% of the pixels.

Hold the phone, this is far too clever. [Eduardo] needed to flash an ESP-12 module before soldering it onto a PCB. The usual way of doing this is with an absurd pogo pin jig. You know what’s cheaper than pogo pins? Safety pins. Clever overwhelming.

Finally – A Big-Screen Vectrex

The Vectrex is in no way the most popular console of all time, but it is one of the more unique. Eschewing typical raster-based rendering, it instead relies on a vector-based display. Since the average home television of the era would be completely unable to display such signals, the Vectrex had its screen built in. This got [Arcade Jason] wondering – would it be possible to hook the Vectrex up to a bigger screen?

First, a suitable monitor had to be found. The 19V2000 turned out to be a good candidate – much larger at 19 inches, and found in a variety of arcade cabinets from years past. From there, the project became a matter of identifying the signal outputs of the Vectrex. [Arcade Jason] took the liberty of modifying the levels of the signals on the Vectrex board itself, and then fixing the now-overscanned image on the original screen by adjusting the onboard trimpots. With the Vectrex’s X and Y signals now boosted somewhat, they were wired up to the inputs of the larger arcade screen. For the Z signal, things got even hackier – a Walmart “Computer Amplifier”, typically used for speakers, was instead pressed in to service to amplify the signal.

There are plenty of wires running all over the carpet in this video, but the fact is, it works brilliantly. Future plans involve upgrading to an even larger 23 inch monitor, and possibly even experiments with color vector displays. It just goes to show that the Vectrex, even today, maintains a die-hard following.

Perhaps you’d like to try this, but need to fix your original Vectrex screen first? Never fear – that’s possible, too.


Add Intuitiveness to OpenSCAD With Encoders

The first time I saw 3D modeling and 3D printing used practically was at a hack day event. We printed simple plastic struts to hold a couple of spring-loaded wires apart. Nothing revolutionary as far as parts go but it was the moment I realized the value of a printer.

Since then, I have used OpenSCAD because that is what I saw the first time but the intuitiveness of other programs led me to develop the OpenVectorKB which allowed the ubiquitous vectors in OpenSCAD to be changed at will while keeping the parametric qualities of the program, and even leveraging them.

All three values in a vector, X, Y, and Z, are modified by twisting encoder knobs. The device acts as a keyboard to

  1. select the relevant value
  2. replace it with an updated value
  3. refresh the display
  4. move the cursor back to the starting point

There is no software to install and it runs off a Teensy-LC so reprogramming it for other programs is possible in any program where rotary encoders may be useful. Additional modes include a mouse, arrow keys, Audacity editing controls, and VLC time searching.

Here’s an article in favor of OpenSCAD and here’s one against it. This article does a good job of explaining OpenSCAD.

Continue reading “Add Intuitiveness to OpenSCAD With Encoders”

Shapes Made From Light, Smoke, and A Lot of Mirrors

Part lightshow, part art piece, part exploratory technology, Light Barrier (third edition) by South Korean duo [Kimchi and Chips] crafts a visual and aural experience of ephemeral light structures using projectors, mirrors, and a light fog.

Presently installed at the ACT Center of Asia Culture Complex in Gwangju, South Korea, Light Barrier co-ordinates eight projectors, directing their light onto a concave cluster of 630 mirrors. As a result, an astounding 16 million ‘pixel beams’ of refocused light simulate shapes above the array.  The array itself was designed in simulation using an algorithm which — with subtle adjustments to each mirror — “grew” the display so as to line up the reflecting vectors. Upon setup, final calibration of the display used Rulr to treat each ‘pixel beam’ as a ray in 3D space to ensure image accuracy once the show began. Check out a preview after the break! Continue reading “Shapes Made From Light, Smoke, and A Lot of Mirrors”

Amazing Oscilloscope Graphics

From what we can understand, [ompuco] has built a 2D audio output on top of the Unity game engine, enabling him to output X and Y values from his stereo soundcard straight to an oscilloscope in XY mode. His code simply scans through all the vertexes in the scene and outputs the right voltages into the left and right audio streams. He’s using this to create some pretty incredible animations. Check out the video “additives” below for an example. (See if you can figure out what’s being “added”.)

Continue reading “Amazing Oscilloscope Graphics”

32C3: Vector Video Games

There are a few classic video games that rely on vector graphics and special monitors. Asteroids is incomplete if you’re not playing it in its original arcade format. The same goes with Tempest, Lunar Lander, and the 1983 Star Wars arcade game. Emulation of these games is possible, even with MAME, but the display – like every display you can buy today – is still rasterized. The solution to this problem is to create a vector display output for MAME that works in conjunction with adapter boards and DACs connected to a monitor.

For this year’s Chaos Computer Congress, that’s exactly what [Trammell Hudson] and [Adelle Lin] did. They’ve created an open source vector gaming system that connects MAME to XY monitors and oscilloscopes.

The build uses a custom board equipped with a Teensy 3.1 microcontroller and a 12-bit DAC to convert XY coordinates sent by MAME to vectors that can be displayed on any XY monitor. This, of course, requires a patch to MAME, which the maintainers rejected as being an, “unacceptably hacky way to achieve the intended result.” It does achieve the intended result, though: allowing dozens of vector games playable on whatever monitor supports vector graphics.

So far, [Trammell] and [Adelle] have gotten their system working on Vectrex consoles, analog oscilloscopes set to XY mode, and vectorscopes that litter every broadcast station and surplus shop. Check out [Trammell] and [Adelle]’s talk, and if you want to build the V.st vector display driver, the board is available from OSHPark.

Paper Topo Models with Vector Cutter

If there’s a science fair coming up, this trumps just about any 2D poster. It’s a 3D topographical map of an inactive Slovakian volcano, Poľana. [Peter Vojtek] came up an easy way to generate SVG topo patterns using Ruby.

Topographical data is available through the MapQuest API. You should be able to model just about any part of the world, but areas with the greatest elevation difference are going to yield the most interesting results. The work starts by defining a rectangular area using map coordinates and deciding the number of steps (sheets of paper representing this rectangle). The data are then chopped up into tables for each slice, converted to SVG points, and a file is spit out for the blade cutting machine. Of course you could up the game and laser cut these from more substantial stock. If you have tips for laser-cutting paper without singing the edges let us know. We’ve mostly seen failure when trying that.

The red model explained in [Peter’s] writeup uses small cross-pieces to hold the slices. We like the look of the Blue model which incorporates those crosses in the elevation representation. He doesn’t explain that specifically but it should be easy to figure out — rotate the rectangle and perform the slicing a second time, right?

If you’re looking for more fun with topography we’ve always been fond of [Caroline’s] bathymetric book.