Suntracker Optimizes Solar Panels While Visualizing Sun’s Path

August 18, 2019 by 31 Comments

If you have solar panels, you want soak up as much sunshine as you can to get your money’s worth. If you don’t have space for a lot of panels, the next best thing is repositioning the panels to catch the most rays. For his entry into the Hackaday Prize, [Frank] built a gorgeous solar tracker prototype to both validate his theories and to serve as a learning platform.

A solar tracker’s purpose is — you guessed it — tracking the Sun’s location to determine optimal positioning for solar panels and other sun-seeking payloads. In the latest revision, [Frank]’s tracker follows the Sun’s azimuth angle, aka its horizontal movement.

The Sun’s path is represented along a ring of 32 red/green LEDs. It moves around the ring as a green LED, according to a real-time clock and a set of pre-determined solar positions stored on an SD card.

Two red LEDs show the sunrise and sunset azimuth angles, and a third LED indicates North as detected with a magnetometer and adjusted for local magnetic declination. In the center of the ring, a stepper motor drives an arrow that always points at the Sun LED. As the tracker is moved around, all the LEDs shift around the ring to follow their targets.

Though it already shines, we think this ongoing project has a bright future. Be sure to check out the demo video after the break.

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An All-In-One Conference Video Streaming Box

August 18, 2019 by No comments

When running a hacker camp or other event, one of the many challenges faced by the organisers concerns the production and distribution of event videos. As the talks are recorded they must be put online, and with a load of talks to be processed it quickly becomes impractical to upload them one by one through a web interface such as that provided by YouTube. At the BornHack 2019 hacker camp in Denmark they were using a particularly well-integrated unit to do the video uploading in real time, and its creator [Mikkel Mikjær Christensen]  was good enough to share the video we’ve put below the break, a talk he gave about it at The Camp 2017, a Danish open source software camp.

It takes the viewer through the evolution over several years, from simple camcorders with integrated microphones and post-event processing, through a first-generation system with a laptop and rack-mount monitors, and into a final system in a rugged portable case with a significantly powerful laptop running OBS with a hardware MPEG encoder. Careful choice of power supplies and the use of good quality wireless microphones now give instantaneous video streaming to events such as BornHack without the need for extensive infrastructure.

If you were wondering where you might have heard that name before, [Mikkel] is the [Mike] from the Retrocomputing with Mike YouTube channel. It’s being honest to say that more of our conversation was about retrocomputers than the video box.

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Turning Scrap Metal Into Something To Work With

August 18, 2019 by 19 Comments

Blacksmiths will frequently work to a customer’s commission, and sometimes those commissions can be somewhat unusual. [Copperrein] had just such a piece of work come his way, a ceremonial sword to be made from a supplied collection of iron and steel items. To render them into something useful he had to melt them together, and the story of how he did that is particularly interesting.

We’re introduced to the Aristotle furnace, a fairly simple top-fed air blast charcoal furnace capable of melting almost any ferrous scrap into a so-called “bloom”, a lump of iron with some slag and carbon inclusions. These furnaces are often built as holes in the ground, but he’s made his atop a portable forge at working height to save bending over it for seven hours.

The source material was a very mixed bag, so the first order was to strip it in an acid bath of any coatings which might contaminate the resulting bloom. The parts, including things as diverse as a huge wrought-iton bolt, a scythe blade, and a pair of dividers, were then cut into small pieces one by one and fed into the furnace. They melt as they progress down through the furnace, resulting in a bloom of iron. The bloom is impure and will need significant working to expel any inclusions, but the final result will be something like the wrought iron of old. Let’s hope he has a power hammer, working the bloom would be hard work by hand!

If this catches your attention, you may be interested in a bit of blast furnace iron smelting. And of course, there is also our ongoing blacksmithing series to get you going at the anvil. You could even make a nail.

Via Reddit.

Thanks [Mike] for the tip.

ArduRover Boat Uses Tub To Float

August 18, 2019 by 16 Comments

There’s nothing quite like the sight of a plastic box merrily sailing its way around a lake to symbolise how easy it is to get started in autonomous robotics. This isn’t a project we’re writing about because of technical excellence, but purely because watching an autonomous plastic box navigate a lake by itself is surprisingly compelling viewing. The reason that [rctestflight] built the vessel was to test out the capabilities of ArduRover. ArduRover is, of course, a flavour of the extremely popular open source ArduPilot, and in this case is running on a Pixhawk.

The hardware itself is deliberately as simple as possible: two small motors with RC car ESCs, a GPS, some power management and a telemetry module are all it takes. The telemetry module allows the course/mission to be updated on the fly, as well as sending diagnostic data back home. Initially, this setup performed poorly; low GPS accuracy combined with a high frequency control loop piloting a device with little inertia lead to a very erratic path. But after applying some filtering to the GPS this improved significantly.

Despite the simplicity of the setup, it wasn’t immune to flaws. Seaweed in the prop was a cause of some stressful viewing, not to mention the lack of power required to sail against the wind. After these problems caused the boat to drift off course past a nearby pontoon, public sightings ranged from an illegal police drone to a dog with lights on its head.

If you want to use your autonomous boat for other purposes than scaring the public, we’ve written about vessels that have been used to map the depth of the sea bed, track aircraft, and even cross the Atlantic.

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Adding A Co-Processor To Help SNES Games With Slowdown

August 18, 2019 by 3 Comments

The Super Nintendo port of Gradius III is notable for being close to the arcade original, with its large, bright and colorful graphics. However, due to the limitation of the console’s hardware, the port is also well known for having constant slowdowns during gameplay, particularly during later sections. [Vitor] hacked away at the game and made a patched version of the ROM use a co-processor to eliminate those issues.

The slowdown seen here in Gradius is not uncommon to SNES players, many games of that era suffer from it when several sprites appear on the screen at once. This is partially due to the aging CPU Nintendo chose, supposedly in order to maintain NES backwards compatibility before the idea got scrapped. Unable to complete its tasks by the time the next frame needs to be shown, the hardware skips frames to let the processor catch up before it can continue. This is perceived as the aforementioned slowdown.

Around the later stage of the SNES’s life, games started using additional chips inside the cartridges in order to enhance the console’s performance. One of them is the SA1, which is a co-processor with the same core as the main CPU, only with a higher clock rate. By using it, games had more time to run through the logic and graphics manipulation before the next frame. What [Vitor] did was port those parts of Gradius III to the SA1, essentially making it just like any other enhanced cartridge from back in the day.

Unlike previous efforts we’ve seen to overclock the SNES by giving it a longer blanking time, this method works perfectly on real unmodified hardware. You can see the results of his efforts after the break, particularly around stage 2 where several bubbles fill the screen on the second video.

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Great Artificial Daylight Via Broken TVs

August 17, 2019 by 34 Comments

[DIY Perks] has long been a fan of lights that accurately mimic real daylight. Often choosing high-quality LEDs for his projects, lately he’s taken a different tack – using broken televisions to produce attractive home lighting solutions.

The hack involves removing the backlight from the damaged television or monitor. These have a powerful white light inside, but the real key is that they also features a Fresnel lens. This helps the backlight appear very similar to a real skylight, due to the way it scatters light around the room.

Due to the difficulty of driving most LED and CCFL backlights, the project strips the original lighting out and replaces it with a set of high-CRI LED strips readily available off eBay. These are easily driven from 12 volts and give a white light more similar to actual daylight compared to most backlights. With the LEDs in place, the monitor’s original diffusers and Fresnel lens are put back in place, and the light is finished off with an aluminium frame.

Fitted to an angled ceiling, the light really does look as if actual sunlight is streaming through a window on a rainy day. It’s a pleasant effect that does a great job of lighting a room, and we suspect it would be excellent for general video work, too. [DIY Perks] is no stranger to a good studio light build, after all. Video after the break.

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Enjoy A Refreshing Beverage With The Chilled Drink Calculator

August 17, 2019 by 15 Comments

Hackers are quite often the price conscious type, unwilling to pay jacked up prices for cold beverages when they can be purchased warm and in bulk for much lower cost. However, when guests are on the way and time is running out, it’s crucial to chill the drinks down to the right temperature, and fast. To take the guessing out of the process, [Álvaro Díez] and [Tibor Pal] collaborated to create the Chilled Drink Calculator.

It’s a resource jam-packed full of everything you need to know to get your drinks cold, pronto. Based on heat transfer equations and data from empirical studies, the calculator is able to show you just how long it will take to cool practically any beverage to any temperature. There are presets for different types of container and cooling method, as well as information on the ideal serving temperatures for things like wine, beer and soft drinks. There’s even information on helpful hacks to help cool things down more quickly – with the salt and ice bath being devastatingly effective with minimal equipment requirements.

Keep the calculator in your bookmarks for the next time your pals show up with a case of beer that’s been sitting in the sun all day in the back of a pickup truck (Authors note: looking at you, Terry). Alternatively, consider building an advanced cooling apparatus.