Cheap Speakers Sound Good With Easy Open Baffle Design

May 29, 2020 by 20 Comments

If you’ve spent any time around audio gear at all, you’ll know that enclosure design is as critical as the speaker drivers themselves. [Frank Olson] demonstrates this ably, with his open baffle design for some cheap off-the-shelf speakers.

[Frank]’s aim was to do a comparison between using no enclosure, and an open baffle design, with a pair of 2″ full-range speakers. These drivers are nothing special; just a low-cost part that you’d find in any cheap set of computer speakers. [Frank] screws the drivers into a thin, flat wooden board, and then adds a supporting strut to allow the speakers to stand on their own.

The comparison makes it clear that even this basic baffle design makes a big difference to perceived sound quality. Bass is fuller, and the sound is far improved thanks to the baffle blocking out of phase sounds from the rear of the speaker.

It’s a technique that could prove useful to anyone quickly trying to rig up an audio setup for the workshop or makerspace out of leftover parts. We’ve featured similar projects before that espouse the benefit of enclosure design when using even very affordable speakers. Video after the break.

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Tarot Machine Flips Through Fate’s Rolodex

May 29, 2020 by 8 Comments

Were tarot card readers deemed non-essential in your part of the world (and do you think they saw it coming?) More than ever, we all need diversions that are for entertainment purposes only. And what better basis for entertainment than a mystical fortune-telling robot that can read your tarot cards?

This fantastic-looking ‘bot stands on the shoulders of [Scott Bezak]’s trailblazing method for easy DIY split-flap displays. Push the rather inviting-looking button on the top, and the flaps start flipping around to find your fortune. Once the fates have aligned, a thermal printer on the front spits out an image of your card along with an interpretation.

It’s obvious that [i_mozy] put quite a lot of effort into this slick machine, and we think the stickers look especially great. All the details of physical tarot card readings are accounted for, including a random number to decide the card’s position, and LEDs to represent the card’s element. Suspend your disbelief and check out the demo/promo video after the break.

Split-flap displays are a great choice no matter what you want to show. We’ve seen them used to display everything from the weather to the current Spotify track.

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Books You Should Read: The Design Of Everyday Things

May 29, 2020 by 27 Comments

With everything from APIs to Raspberry Pis making it even easier for us to create and share objects shaped by personal whim, it’s high time that Don Norman’s sage design advice falls on not just the design student, but the hardware hacker and DIY enthusiast too. Grab yourself a coffee and a free weekend, and settle into the psychology of people-struggling-how-to-use-that-widget-they-just-purchased in The Design of Everyday Things: Revised and Expanded Edition.

Who’s to blame for a door that opens with a pull when everything about how it looks says it should open with a push? In Don Norman’s world, it’s not you; its the designer. Enter a world where blame is inverted and mistakes can be critically categorized. Norman takes us example by example showing us how common items in the world poorly serve the needs of their user, mainly because the designer simply ignores key aspects of our humanity. This book is a crisp, concise overview of human psychology when applied to engaging with things combined with a language of ideas to help us apply this psychology to better interactions. (And it reads like butter!)

Opening Up to the Language of Design

What’s an affordance, you might ask? Well, simply put, it’s a way that an object can be used by a human. How about a signifier? That’s a communication “signposting” scheme that object uses to suggest to you how it should be used. If that sounds a bit fluffy, just think about the last time you tried to push open a door that needed to be pulled. Something about that door was suggesting that you could push it open, but it couldn’t! It “fooled” you because all the object’s signifiers were telling you otherwise. Continue reading “Books You Should Read: The Design Of Everyday Things” →

Hackaday Podcast 069: Calculator Controversy, Socketing SOIC, Metal On The Moon, And Basking In Bench Tools

May 29, 2020 by No comments

Hackaday editors Mike Szczys and Elliot Williams march to the beat of the hardware hacking drum as they recount the greatest hacks to hit the ‘net this week. First up: Casio stepped in it with a spurious DMCA takedown notice. There’s a finite matrix of resistors that form a glorious clock now on display at CERN. Will a patio paver solve your 3D printer noise problems? And if you ever build with copper clad, you can’t miss this speedrun of priceless prototyping protips.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

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Steampunk Brushless Motor Demo Pushes All The Maker Buttons

May 29, 2020 by 46 Comments

We’ll be honest right up front: there’s nothing new in [David Cambridge]’s brushless motor and controller build. If you’re looking for earth-shattering innovation, you’d best look elsewhere. But if you enjoy an aimless use of just about every technique and material in the hacker’s toolkit employed with extreme craftsmanship, then this might be for you. And Nixies — he’s got Nixies in there too.

[David]’s build started out as a personal exploration of brushless motors and how they work. Some 3D-printed parts, a single coil of wire, and a magnetic reed switch resulted in a simple pulse motor that performed surprisingly well. This morphed into a six-coil motor with Hall-effect sensors and a homebrew controller. This is where [David] pulled out all the stops on tools — a lathe, a plasma cutter, a welder, a milling machine, and a nice selection of woodworking tools went into making parts for the final motor as well as an enclosure for the project. And because he hadn’t checked off quite all the boxes yet, [David] decided to use the 3D-printed frame as a pattern for casting one from aluminum.

The finished motor, with a redesigned rotor to deal better with eddy currents, joined the wood and metal enclosure along with a Nixie tube tachometer and etched brass control plates. It’s a great look for a project that’s clearly a labor of self-edification and skill-building, and we love it. We’ve seen other BLDC demonstrators before, but few that look as good as this one does.

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This Week In Security: Leaking Partial Bits, Apple News, And Overzealous Contact Tracing

May 29, 2020 by 11 Comments

Researchers at the NCCGroup have been working on a 5-part explanation of a Windows kernel vulnerability, targeting the Kernel Transaction Manager (KTM). The vulnerability, CVE-2018-8611, is a local privilege escalation bug. There doesn’t seem to be a way to exploit this remotely, but it is an interesting bug, and NCCGroup’s work on it is outstanding.

They start with a bit of background on what the KTM is, and why one might want to use it. Next is a handy guide to reverse engineering Microsoft patches. From there, they describe the race condition and how to actually exploit it. They cover a wide swath in the series, so go check it out.

Left4Dead 2

Just a reminder that bugs show up where you least expect them, [Hunter Stanton] shares his story of finding a code execution bug in the popular Valve game, Left4Dead 2. Since the game’s code isn’t available to look at, he decided to go the route of fuzzing. The specific approach he took was to fuzz the navigation mesh data, part of the data contained in each game map. Letting the Basic Fuzzing Framework (BFF) run for three days turned up a few possible crashes, and the most promising turned out to have code execution potential. [Hunter] submitted the find through Valve’s HackerOne bug bounty program, and landed a cool $10k bounty for his trouble.

While it isn’t directly an RCE, [Hunter] does point out that malicious mesh data could be distributed with downloadable maps on the Steam workshop. Alternatively, it should be possible to set up a fake game server that distributes the trapped map. Continue reading “This Week In Security: Leaking Partial Bits, Apple News, And Overzealous Contact Tracing” →

Toilet Paper Chase And Indoor Cycling Race With Unity And Arduino

May 29, 2020 by 4 Comments

While we’re still far away from returning to a pre-Corona everyday life, people seem to have accepted that toilet paper will neither magically cease to exist, nor become our new global currency. But back at the height of its madness, like most of us, [Jelle Vermandere] found himself in front of empty shelves, and the solution seemed obvious to him: creating a lifelike toilet paper chasing game in hopes to distract the competition.

Using Unity, [Jelle] created a game world of an empty supermarket, with the goal to chase after distribution tubes and collect toilet paper packs into a virtual cart. Inspired by the Wii Wheel, he imitated a shopping cart handle built from — as it appears — a sunshade pole that holds an Arduino and accelerometer in a 3D-printed case as game controller. For an even more realistic feel, he added a sound sensor to the controller, and competing carts to the game, which can be pushed out of the way by simply yelling loud enough. You can witness all of this delightful absurdity in his build video after the break.

From racing shopping carts to racing bicycles

But that’s not all. With the toilet paper situation sorted out, [Jelle] found himself in a different dilemma: a cloud foiled his plans of going for a bicycle ride. In the same manner, he ended up building a cycling racing game, once again with Unity and Arduino. From a 3D-scanned model of himself and his bicycle, to automatically generating tracks on the fly and teaching an AI to ride a bike, [Jelle] clearly doesn’t joke around while he’s joking around.

However, the best part about the game has to be the controller, which is his actual bicycle. Using a magnetic door sensor to detect the speed, and a potentiometer mounted with an obscure Lego construction to the handlebar, it’s at least on par with the shopping cart handle — but judge for yourself in another build video, also attached after the break. The only thing missing now is to level up the difficulty by powering the Arduino with the bicycle itself.

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