Year: 2020

Fiber Optic Ceiling Pumps To The Beat

June 17, 2020 by 3 Comments

For years [Centas] dream was to take the stars to his home and build a fiber optic ceiling. Even though there are many fiber optic star ceiling kits commercially available, we are glad he decided to go full DIY on this project as the result is simply astonishing.

[Centas] chose to make a model of a section of the sky as it is visible from his home and generated a map of 1,200 stars with the planetarium software Celestia. The most time-consuming part of making a star ceiling is always poking lots of holes for the fibers. In [Cenas] case this turned out to be especially cumbersome as he decided to install the fibers after hanging the ceiling panel so he came up with a method to catch the fiber with a fishing pole after pushing it through from the bottom. The finished ceiling looks really great though with its rounded edges that contain RGB LED strips for side illumination. [Cenas] also painted the ceiling after installing the fibers so they are not visible when they are not lit but there is still enough light shining through the paint.

Continue reading “Fiber Optic Ceiling Pumps To The Beat” →

Hands On With A Batteryless E-Paper Display

June 17, 2020 by 64 Comments

E-paper displays are unusual in that power is only needed during a screen update. Once the display’s contents have been set, no power whatsoever is required to maintain the image. That’s pretty nifty. By making the display driver board communicate wirelessly over near-field communication (NFC) — which also provides a small amount of power — it is possible for this device to be both wireless and without any power source of its own. In a way, the technology required to do this has existed for some time, but the company Waveshare Electronics has recently made easy to use options available for sale. I ordered one of their 2.9 inch battery-less NFC displays to see how it acts.

Continue reading “Hands On With A Batteryless E-Paper Display” →

Fail Of The Week: How Not To Watercool A PC

June 17, 2020 by 50 Comments

To those who choose to overclock their PCs, it’s often a “no expense spared” deal. Fancy heat sinks, complicated liquid cooling setups, and cool clear cases to show off all the expensive guts are all part of the charm. But not everyone’s pockets are deep enough for off-the-shelf parts, so experimentation with cheaper, alternatives, like using an automotive fuel pump to move the cooling liquid, seems like a good idea. In practice — not so much.

The first thing we thought of when we saw the title of [BoltzBrain]’s video was a long-ago warning from a mechanic to never run out of gas in a fuel-injected car. It turns out that the gasoline acts as a coolant and lubricant for the electric pump, and running the tank dry with the power still applied to the pump quickly burns it out. So while [BoltzBrain] expected to see corrosion on the brushes from his use of water as a working fluid, we expected to see seized bearings as the root cause failure. Looks like we were wrong: at about the 6:30 mark, you can see clear signs of corrosion on the copper wires connecting to the brushes. It almost looks like the Dremel tool cut the wire, but that green copper oxide is the giveaway. We suspect the bearings aren’t in great shape, either, but that’s probably secondary to the wires corroding.

Whatever the root cause, it’s an interesting tour inside a common part, and the level of engineering needed to build a brushed motor that runs bathed in a highly flammable fluid is pretty impressive. We liked the axial arrangement of the brushes and commutator especially. We wonder if fuel pumps could still serve as a PC cooler — perhaps changing to a dielectric fluid would do the trick.

Continue reading “Fail Of The Week: How Not To Watercool A PC” →

DIY Plastic Speedboat For One

June 17, 2020 by 32 Comments

Coroplast (short for corrugated plastic) is an interesting material. It has a structure similar to cardboard, but since it’s plastic it’s waterproof and can be used for a unique set of applications. It’s typically used for political yard signs, but there are more fun things to do with this lightweight material than advertise. [Paul Elkins], for example, uses it to make speedboats.

The boats that [Paul] builds make use of a piece of coroplast which he cuts and folds into a basic hull shape. From there he begins to assemble the other things needed to finalize the boat, including strengthening the shape with wood, adding a steering wheel, building a transom to mount the motor to, and placing controls in the cockpit such as throttle and steering. The entire build is enough to propel a single person on a body of water at about five knots, which is impressive.

To make one of these yourself you’ll need a small outboard motor, but all of the other details of the build are outlined clearly in his series of videos. If you want to build your own boat but don’t like the idea of a noisy two-stroke motor right behind you, you can also look into building a boat with a silent mode of propulsion.

And if you’ve got a good supply of Coro, definitely check out [Paul]’s other projects, including a tiny house.

Continue reading “DIY Plastic Speedboat For One” →

Compile A Hydroponics System From Source

June 16, 2020 by 18 Comments

Tending to a garden is usually a rewarding endeavor, as long as there is good soil to work with. If there isn’t, it can either get frustrating quickly having to deal with soils like sand or hard clay, or it can get expensive by having to truck in compost each year. Alternatively, it’s possible to set up systems of growing plants that don’t need any soil at all, although this requires an automated system otherwise known as hydroponics to manage water and nutrients sent to the plants.

This setup by [Kyle] is unique in that it uses his own open-source software which he calls Mycodo to control the hydroponic system. It is loaded onto a Raspberry Pi 4 (which he notes can now be booted from a USB drive instead of an SD card) which controls all of the peripherals needed for making sure that the water has the correct amount of nutrients and chemical composition.

The build is much more than just a software control panel, though. [Kyle] walks through every part of setting up a small hydroponic system capable of effectively growing 15-20 plants indoors. He grows varieties of lettuce and basil, but this system can work for many more types of plants as well. With just slight variations, a similar system can not only grow plants like these, but fish as well.

Continue reading “Compile A Hydroponics System From Source” →

Disable Intel’s Backdoor On Modern Hardware

June 16, 2020 by 42 Comments

While the Intel Management Engine (and, to a similar extent, the AMD Platform Security Processor) continues to plague modern computer processors with security risks, some small progress continues to be made for users who value security of the hardware and software they own. The latest venture in disabling the ME is an ASRock motherboard for 8th and 9th generation Intel chips. (There is also a link to a related Reddit post about this project).

First, a brief refresher: The ME is completely removable on some computers built before 2008, and can be partially disabled or deactivated on some computers built before around 2013. This doesn’t allow for many options for those of us who want modern hardware, but thanks to a small “exploit” of sorts, some modern chipsets are capable of turning the ME off. This is due to the US Government’s requirement that the ME be disabled for computers in sensitive applications, so Intel allows a certain undocumented bit, called the HAP bit, to be set which disables the ME. Researchers have been able to locate and manipulate this bit on this specific motherboard to disable the ME.

While this doesn’t completely remove the firmware, it does halt all execution of code in a way that is acceptable for a large governmental organization, so if you require both security and modern hardware this is one of the few ways to achieve that goal. There are other very limited options as well, but if you want to completely remove the ME even on old hardware the process itself is not as straightforward as you might imagine.

Header image: Fritzchens Fritz from Berlin / CC0

Arduino Reduces Heating Costs

June 16, 2020 by 29 Comments

While almost everyone has a heater of some sort in their home, it’s fairly unlikely that the heat provided by a central heating system such as a furnace is distributed in an efficient way. There’s little reason to heat bedrooms during the day, or a kitchen during the night, but heating systems tend to heat whole living space regardless of the time of day or the amount of use. You can solve this problem, like most problems, with an Arduino.

[Karl]’s build uses a series of radiator valves to control when each room gets heat from a boiler. The valves, with a temperature monitor at each valve, are tied into a central Arduino Mega using alarm wiring. By knowing the time of day and the desired temperature in each room, the Arduino can control when heat is applied to each room and when it is shut off, presumably making the entire system much more efficient. It also has control over the circulating pump and some of the other boiler equipment.

Presumably this type of system could be adapted to a system which uses a furnace and an air handler as well, although it is not quite as straightforward to close vents off using a central unit like this as it is to work with a boiler like [Karl] has. With careful design, though, it could be done. Besides replacing thermostats, we can’t say we’ve ever seen this done before.

Thanks to [SMS] for the tip!