Author: Bryan Cockfield

1760 Articles

Open-Source Solar Modules

February 5, 2024 by 13 Comments

As the price of solar panels continues to fall, more and more places find it economical to build solar farms that might not have been able to at higher prices. High latitude locations, places with more clouds than sun, and other challenging build sites all are seeing increased green energy development. The modules being used have one main downside, though, which is that they’re essentially a black box encased in resin and plastic, so if one of the small cells fails a large percentage of the panel may be rendered useless with no way to repair it. A solar development kit like this one from a group called Biosphere Solar is looking to create repairable, DIY modules that are completely open source, to help solve this issue.

The modular solar panel is made from a 3D printed holster which can hold a number of individual solar cells. With the cells placed in the layout and soldered together, they are then sandwiched between a few layers of a clear material like acrylic or glass with a seal around the exterior to prevent water intrusion. Since the project is open-source any number of materials can be used for the solar cell casing, and with the STL file available it’s not strictly necessary to 3D print the case as other manufacturing methods could be used. The only thing left is to hook up a DC/DC converter if you need one, and perhaps also a number of bypass and/or blocking diodes depending on your panel’s electrical layout.

The project is still in active development, and some more information can be found at the project’s website. While the “recyclability” of large-scale solar farms is indeed a problem, it’s arguably one which has been overblown by various interests who are trying to cast doubt on green energy. A small build like this won’t solve either problem anytime soon, so the real utility here would be for home users with small off-grid needs who want an open-source, repairable panel. It’s a great method to make sure solar technology is accessible and repairable for anyone that wants it, and in a way this approach to building hardware reminds us a lot of the Framework laptops.

HF In Small Spaces

February 3, 2024 by 22 Comments

Generally, the biggest problem a new ham radio operator will come across when starting out on the high frequency (HF) bands is finding physical space for the antennas. For a quick example, a dipole antenna for the 20 m band will need around 10 m of wire, and the lower frequencies like 80 m need about four times as much linear space. But if you’re willing to trade a large space requirement for a high voltage hazard instead, a magnetic loop antenna might be just the ticket.

Loop antennas like these are typically used only for receiving, but in a pinch they can be used to transmit as well. To tune the antennas, which are much shorter than a standard vertical or dipole, a capacitor is soldered onto the ends, which electrically lengthens the antenna. [OM0ET] is using two loops of coax cable for the antenna, with each end soldered to one half of a dual variable capacitor which allows this antenna to tune from the 30 m bands to the 10 m bands, although he is using it mostly for WSPR on 20 m. His project also includes the use of an openWSPR module, meaning that he doesn’t have to dedicate an entire computer to run this mode.

The main downsides of antennas like these is that they are not omnidirectional, are not particularly good at transmitting, and develop a significantly high voltage across the capacitor as this similar mag loop antenna project demonstrated. But for those with extreme limitations on space or who, like [OM0ET] want a simple, small setup for running low-power applications like WSPR they can really excel. In fact, WSPR is a great mode for getting on the air at an absolute minimum of cost.

Continue reading “HF In Small Spaces” →

Satellite Provides Detailed Data On Antarctic Ice

February 2, 2024 by 19 Comments

Ever since the first satellites started imaging the Earth, scientists have been using the data gathered to learn more about our planet and improve the lives of its inhabitants. From weather forecasting to improving crop yields, satellites have been put to work in a wide array of tasks. The data they gather can go beyond imaging as well. A new Chinese satellite known as Fengyun-3E is using some novel approaches to monitor Antarctic sea ice in order to help scientists better understand the changing climate at the poles.

While it is equipped with a number of other sensors, one of the more intriguing is a piece of equipment called WindRad which uses radar to measure wind at various locations and altitudes based on how the radar waves bounce off of the atmosphere at various places.  Scientists have also been able to use this sensor to monitor sea ice, and can use the data gathered to distinguish new sea ice from ice which is many years old, allowing them to better understand ice formation and loss at the poles. It’s also the first weather satellite to be placed in an early morning orbit, allowing it to use the long shadows cast by the sun on objects on Earth’s surface to gather more information than a satellite in other orbits might be able to.

With plenty of other imaging sensors on board and a polar orbit, it has other missions beyond monitoring sea ice. But the data that it gathers around Antarctica should give scientists more information to improve climate models and understand the behavior of sea ice at a deeper level. Weather data from satellites like these isn’t always confined to academia, though. Plenty of weather satellites broadcast their maps and data unencrypted on radio bands that anyone can access.

Resistor Swap Gives Honda Insights More Power

January 31, 2024 by 123 Comments

A common complaint around modern passenger vehicles is that they are over-reliant on electronics, from overly complex infotainment systems to engines that can’t be fixed on one’s own due to the proprietary computer control systems. But even still, when following the circuits to their ends you’ll still ultimately find a physical piece of hardware. A group of Honda Insight owners are taking advantage of this fact to trick the computers in their cars into higher performance with little more than a handful of resistors.

The relatively simple modification to the first-generation Insight involves a shunt resistor, which lets the computer sense the amount of current being drawn from the hybrid battery and delivered to the electric motor. By changing the resistance of this passive component, the computer thinks that the motor is drawing less current and allows more power to be delivered to the drivetrain than originally intended. With the shunt resistor modified, which can be done with either a bypass resistor or a custom circuit board, the only other change is to upgrade the 100 A fuse near the battery for a larger size.

With these two modifications in place, the electric motor gets an additional 40% power boost, which is around five horsepower. But for an electric motor which can output full torque at zero RPM, this is a significant boost especially for a relatively lightweight car that’s often considered under-powered. It’s a relatively easy, inexpensive modification though which means the boost is a good value, although since these older hybrids are getting along in years the next upgrade might be a new traction battery like we’ve seen in the older Priuses.

Thanks to [Aut0l0g1c] for the tip!

Swapping Nunchucks For A Steering Wheel

January 30, 2024 by 4 Comments

Rather than chasing pure performance and high quality graphics like other gaming companies, Nintendo has made a name for themselves over the last few decades by favoring not only artistic design and gameplay, but the physical design of the game systems. Of course the hybrid handheld Switch console is among these, but it also includes things like the novel design of the Nintendo 64 controller and, of course, the Wii nunchuck controllers. They’re not always met with resounding approval, though. Some of us tend to prefer more traditional gamepad design, and will go to extreme lengths to get it like this D-pad for playing Mario Kart Wii.

Rather than simply building a compatible controller for the Wii, or even using a GameCube controller, this controller setup takes a more roundabout approach. A Wiimote is placed in a holster built from Lego, and the game is set up to recognize it as if it were being used in its steering wheel mode. The Lego holster has a servo attached which can tilt the Wiimote from side to side, mimicking a player holding it to play the game, with another set of servos set up to press the various buttons. To control the controller, a homebrew D-pad built on perfboard with an Arduino at its core is used to send commands to the servos, allowing for a more standard controller layout to be used for the classic kart racing game than the steering wheel Wiimote allows.

While it’s quite obvious that there are simpler, easier solutions that avoid the sometimes awkward nature of using Wiimotes, we certainly appreciate the Rube Goldberg-like approach to setting up your gaming experience exactly the way you like. Whether that’s setting up an antique CRT effect for the authentic retro gaming experience or building a complete racing simulator from scratch, the gaming experience is ripe for personalization and unique builds like this one.

Continue reading “Swapping Nunchucks For A Steering Wheel” →

Ground-Effect Vehicle To Carry Passengers Around Hawaii

January 27, 2024 by 31 Comments

Although Hawaii used to have a ferry service to access the various islands in the archipelago, due to environmental and political issues, air travel is now the only way to island-hop. Various companies have tried to fill this transportation gap, but have all been stymied for one reason or another. The latest to attempt to solve this problem is a unique one, however. The Hawaii Seaglider Initiative is currently testing a ground-effect vehicle for inter-island passenger service that hopes to use the unique characteristics of this type of aircraft to reduce costs and limit environmental concerns.

The Seaglider, with backing from the Hawaii state government and various corporate interests like Hawaiian Airlines, is actually an amalgamation of three different types of vehicle. It’s capable of operating like a normal, hulled boat at low speeds but has a hydrofoil for operating at higher speeds. Beyond that, its wings give it enough lift to leave the water but stay in ground-effect flight, flying low to the water to reduce drag and improve lift when compared to an aircraft flying out of the ground effect. The efficiency gains from this type of flight are enough that the Seaglider can use electric motors and batteries to make the trips from island to island.

While the ferry is not yet in service, flight testing of the vehicle is scheduled for this year. Ground-effect vehicles of this type do have a large number of obstacles to overcome, whether they’re huge military vehicles like the Ekranoplanes of the Soviet Union or even small remote-controlled crafts, including difficulty with rough seas and having to operate in a harsh salt water environment.

A General-Purpose PID Controller

January 27, 2024 by 19 Comments

For those new to fields like robotics or aerospace, it can seem at first glance that a problem like moving a robot arm or flying an RC airplane might be simple problems to solve. It turns out, however, that control of systems like these can get complicated quickly; so much so that these types of problems have spawned their own dedicated branch of engineering. As controls engineers delve into this field, one of their initial encounters with a control system is often with the PID controller, and this open source project delivers two of these general-purpose controllers in one box.

The dual-channel PID controller was originally meant as a humidity and temperature controller and was based on existing software for an ATmega328. But after years of tinkering, adding new features, and moving the controller to an ESP32 platform, [knifter] has essentially a brand new piece of software for this controller. Configuring the controller itself is done before the software is compiled, and it includes a GUI since one of the design goals of the project was ease-of-use. He’s used it to control humidity, temperature and CO2 levels in his own work at the University of Amsterdam, but imagines that it could see further use outside of his use cases in things like reflow ovens which need simple on/off control or for motors which can be controlled through an H-bridge.

The PID controller itself seems fairly robust, and includes a number of features that seasoned controls engineers would look for in their PID controllers. There are additionally some other open-source PID controllers to take a look at like this one built for an Arduino, and if you’re still looking for interesting use cases for these types of controllers one of our favorites is this PID controller built into a charcoal grill.