Animated GIFs On An Apple II

July 22, 2013 by 15 Comments

Before the Internet, computer enthusiasts needed to get their cat pictures, image macros, and animated gifs somehow. If only [Nate] was writing code back in the 80s: he created a video player for the Apple II, essentially turning the classic computer into a machine that can play one or two animated gifs.

Vintage microcomputers aren’t especially noted for a huge amount of RAM, or being very fast, so [Nate] needed to bring in some extra hardware to give his recently acquired Apple II+ a 64k RAM disk to store the gifs.

The gifs are loaded off the floppy drive after being converted on a PC with a Python script, reducing the resolution and colors to 280 x 192 pixels and an amazing rainbow of four colors. For some gifs, seen below, it’s actually slightly impressive an Apple II can pull off this trick. It’s amazing  [Nate] got this thing to work, as well.

If you have an Apple II set up, you’re awesome. You should go peruse [Nate]’s git and make your own animated gifs for your awesome classic computer.

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Complex Camera Rig Controlled With Blender 3D

July 22, 2013 by 11 Comments

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This is a pretty intricate camera mount. Not only does it provide pan and tilt as the subtitles state, but it moves along a track and offers zoom and focus controls. Its great, but you’ll need an equally complex set of controls to do anything meaningful with it. That’s where the real hack comes into play. The entire system is controlled by its virtual model in Blender 3D.

You probably already know that Blender 3D is an open source 3-dimensional modeling suite. It’s got a mountain of features, which include a framework for animating virtual objects. The camera rig was replicated inside of the software, and includes a skeleton that moves just like the real thing. You can make an animation of how the camera should move, then export and play back those motions on the physical hardware.

Now if you need help making 3D models of your hardware perhaps you should try scanning them.

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Hackaday Links: Sunday, July 21st, 2013

July 21, 2013 by 37 Comments

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Adafruit tears down a set of brainwave cat ears. They’re made by Necomimi and use your brain waves to adjust a pair of plush cat ears on the headgear.

If your desktop computer is sitting on the floor you may have damaged USB dongles by hitting them with your knees. [Megacier] prevents this from happening again by building a flexible dongle link.

Can anyone help [Brian Benchoff] find a datasheet for this International Rectifier 92-O350 so he can fix up his old VT100 terminal?

Here’s a quick example of how to graph data from a Raspberry Pi on the sen.se cloud service.

Have some extra fun with your oscilloscope by displaying any image. This set of conversions starts with a picture and ends with an audio file that will draw it on the scope’s screen.

You’ve probably already heard that the Sikorsky Prize for human powered helicopter has been claimed. If you didn’t see any footage of the flight now’s your chance. [Thanks Adam]

Hardware Store Goods And An Mbed Combine Help Solar Panels Track The Sun

July 21, 2013 by 23 Comments

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If you have the space, and can build a tracking rig cheaply you’ll be able to get a lot more out of your solar panels. That’s because they work best when the sun’s rays are hitting them perpendicular to the surface and not at an angle. [Michael Davis] hit both of those stipulations with this mbed powered solar tracker.

At a garage sale he picked up an antenna motor for just $15. The thing was very old, but still wrapped in the original plastic. It’s beefy enough to move his panels, but he first needed a way to mount everything. After checking his angles he built a base out of wood and used galvanized water pipe as an axle. Cable clamps mate his aluminum angle bracket frame to the pipe. This frame holds the panels securely.

To track the sun he used two smaller cells which aren’t easy to pick out in this image. They are monitored by the mbed microcontroller which measures their output in order to point the assembly in the direction which has the most intense light. A couple of limit switches are included to stop the assembly when it reaches either side.

This technique of using small solar cells as the tracking sensors seems to work well. Here’s another project that took that approach.

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How The Mazes Were Generated For Classic Berzerk Game

July 21, 2013 by 16 Comments

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This is a screenshot from the Atari 5200 version of the classic game Berserk. But the write-up we’re featuring actually looks at the original coin-op version. The maze for each level was established on the fly using a seed number fed into a rudimentary algorithm . Here’s a close look at how the maze building code actually worked.

Recently we saw a talk by Pitfall creator [David Crane] as part of our Retrotechtacular series. That is a real gem of programming history, and one of our favorite take-aways was that the levels were not hardcoded, but built using a random number generator algorithm with a hardcoded seed (so that the game was the same each time you played it). This uses a similar method but with a somewhat random seed.

The maze building was reverse engineered by observing the game in a MAME emulator, and by digging through disassembled code. Each time the code is “cold started” the seed starts out at zero, but from there the room number is used as the next seed. This is fed through a very simple algorithm. It generates directions for the walls, which use s few bit-wise operations to add the pillars inside the rooms.

It’s a great thing to study if you’re writing games for your embedded projects. By generating the room programmatically you don’t use up as much program memory. Of course these days even simple hobby controllers have way more storage to work with than [Alan McNeil] had when he designed Berserk.

[via Reddit]

[Image Source]

Quadruple Backflip And Sticks The Landing

July 21, 2013 by 24 Comments

This must have been a coding nightmare, and let’s not even mention the particulars of the mechanical build. The blurred ball near the center of this image is a robot doing a quadruple backflip before sticking the landing.

To the right is a high bar supported by a wood column and some guy-wires. At the beginning of the video below [Hinamitetu] hangs the robot from the bar where it starts its performance without any real motion. The servo motors whine as it gets ready; quickly getting up to speed with full revolutions around the bar. Oh how we wish there was more background info on the hardware! But we’re perfectly happy making our way through [Hinamitetu’s] video collection, which include other gymnastics disciplines like the floor routine. He even posted his own blooper reel that shows the high bar isn’t always a rosy experience.

If you’re thirsting for more amazing performances you won’t be disappointed by this high wire act.

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Well That’s Finally Over With

July 20, 2013 by 150 Comments

HaD

When the owner of the site wanted to sell Hackaday you guys wanted a Kickstarter to crowdfund the purchase and keep it in the community. I obliged and started a crowdfunding campaign. All things must pass, and I got an email from the owner, [Jason]:

Looks like a nice showing but we won’t hit even 100k
I guess we tried…. I have two solid offers from really cool folks. Will keep you posted.

Yes, that’s right, we’re finally done with the crowdfunding campaign. The end time for the campaign is now set for Monday at noon – you can’t actually delete Indiegogo campaigns – and I’m very, very doubtful it will be funded by then.

I have two words for those who supported Hackaday and this crowdfunding campaign: thank you. It’s astonishing we raised what we did without the infrastructure, licensed business, and non-profit status that would make Hackaday really cool. You guys believe in the future of Hackaday, and I’m very thankful for that.

As for the people who vomited vitriol against me in the comments of the crowdfunding announcement, I also have two words for you.

Even though the dream of a Hackaday owned by the community is dead now, I’m extremely confident we’ll find a better home for Hackaday that will allow us to keep moving forward and allow us to do some really cool things we’ve been thinking about for a while. I’ve spoken with a few of the possible future owners, and let me assure you they’re cool people. No, we won’t be doing grants for builds, but I assure you Hackaday will come out of this better than how it went in.

TL;DR: We didn’t quite get to the best of all possible universes, but things are going to be better than how they were before. Everything’s cool, don’t freak out. We’ll tell you stuff when we know more.