Creating Methane From Captured Carbon Dioxide And The Future Of Carbon Capture

October 7, 2021 by 124 Comments

There’s something intrinsically simple about the concept of carbon (CO2) capture: you simply have the CO2 molecules absorbed or adsorbed by something, after which you separate the thus captured CO2 and put it somewhere safe. Unfortunately, in physics and chemistry what seems easy and straightforward tends to be anything but simple, let alone energy efficient. While methods for carbon capture have been around for decades, making it economically viable has always been a struggle.

This is true both for carbon capture and storage/sequestration (CCS) as well as carbon capture and utilization (CCU). Whereas the former seeks to store and ideally permanently remove (sequester) carbon from the atmosphere, the latter captures carbon dioxide for use in e.g. industrial processes.

Recently, Pacific Northwest National Laboratory (PNNL) has announced a breakthrough CCU concept, involving using a new amine-based solvent (2-EEMPA) that is supposed to be not only more efficient than e.g. the previously commonly used MEA, but also compatible with directly creating methane in the same process.

Since methane forms the major component in natural gas, might this be a way for CCU to create a carbon-neutral source of synthetic natural gas (SNG)? Continue reading “Creating Methane From Captured Carbon Dioxide And The Future Of Carbon Capture” →

DIY Solar Ebike Goes Around The World, We Hope

October 7, 2021 by 47 Comments

[Mark Havran] is on a mission to complete a solo trip around the world on his bicycle. For such a long and arduous trip, unsupported by anything other than what he and his bike can carry, he has devised a unique vehicle with everything he needs to accomplish his journey. This bike has plenty of things we’ve seen before, such as solar panels and an electric motor, but plenty of things that are completely novel as well.

For such long-distance trips, the preferred style of bike for most is a recumbent. This allows the rider to take a more relaxed position while riding and is much more efficient than an upright bike as well. [Mark]’s bike also uses a hub motor in the front wheel powered by a set of lithium ion battery packs. The bike also utilizes four solar panels with three charge controllers (to reduce the impacts of panel shading) laid out with three of the panels on a trailer and a single panel above the bike to give him some shade while riding. [Mark] also built solar tracking abilities into each of the two arrays, allowing the solar panels to automatically rotate around the trailer and bike to more efficiently capture sunlight than a statically-mounted set of panels would be able to. They can also be manually controlled in case of high winds.

From the video linked below, we can see a number of other added features to the bike that will enable it to make such a long trip. First, he is getting a new motor which has a number of improvements over his old one, which he put over 30,000 kilometers on. Second, there are some safety features that deserve a mention such as his lighting setup borrowed from emergency response vehicles, and even includes a fire extinguisher for any catastrophic electrical failures. Of course, if you aren’t optimizing your recumbent electric bike for long distance there are some other modifications you could make to it as well to improve its off-road abilities. Best of luck, Mark!

Continue reading “DIY Solar Ebike Goes Around The World, We Hope” →

the microGPS pipeline

MicroGPS Sees What You Overlook

October 7, 2021 by 45 Comments

GPS is an incredibly powerful tool that allows devices such as your smartphone to know roughly where they are with an accuracy of around a meter in some cases. However, this is largely too inaccurate for many use cases and that accuracy drops considerably when inside such as warehouse robots that rely on barcodes on the floor. In response, researchers [Linguang Zhang, Adam Finkelstein, Szymon Rusinkiewicz] at Princeton have developed a system they refer to as MicroGPS that uses pictures of the ground to determine its location with sub-centimeter accuracy.

The system has a downward-facing monochrome camera with a light shield to control for exposure. Camera output feeds into an Nvidia Jetson TX1 platform for processing. The idea is actually quite similar to that of an optical mouse as they are often little more than a downward-facing low-resolution camera with some clever processing. Rather than trying to capture relative position like a mouse, the researchers are trying to capture absolute position. Imagine picking up your mouse, dropping it on a different spot on your mousepad, and having the cursor snap to a different part of the screen. To our eyes that are quite far away from the surface, asphalt, tarmac, concrete, and carpet look quite uniform. But to a macro camera, there are cracks, fibers, and imperfections that are distinct and recognizable.

They sample the surface ahead of time, creating a globally consistent map of all the images stitched together. Then while moving around, they extract features and implement a voting method to filter out numerous false positives. The system is robust enough to work even a month after the initial dataset was created on an outside road. They put leaves on the ground to try and fool the system but saw remarkably stable navigation.

Their paper, code, and dataset are all available online. We’re looking forward to fusion systems where it can combine GPS, Wifi triangulation, and MicroGPS to provide a robust and accurate position.

Video after the break.

Continue reading “MicroGPS Sees What You Overlook” →

BBC Micro:bit Reads Morse Code With MakeCode

October 6, 2021 by 12 Comments

We always have mixed feelings about the drag-and-drop programming languages. But we were impressed with [SirDan’s] Morse code decoder built with the graphical MakeCode. Granted, it is reading 5 element groups from a button on the BBC micro:bit and not worrying about details such as intercharacter or interelement spacing or word spacing. But it is still a nice demo for MakeCode.

Interestingly, the online editor for MakeCode can apparently simulate well enough to test the program. However, [SirDan] only provides the hex file so we couldn’t try it out. There is a screenshot of the visual code, but you’d have to work out the part that didn’t fit on the screenshot (the data arrays are pretty long).

Continue reading “BBC Micro:bit Reads Morse Code With MakeCode” →

3D-printed wall builder, circa 1930s

Retrotechtacular: 3D-Printed Buildings, 1930s Style

October 6, 2021 by 35 Comments

Here we are in the future, thinking we’re so fancy and cutting edge with mega-scale 3D printers that can extrude complete, ready-to-occupy buildings, only to find out that some clever inventor came up with essentially the same idea back in the 1930s.

The inventor in question, one [William E. Urschel] of Valparaiso, Indiana, really seemed to be onto something with his “Machine for Building Walls,” as his 1941 patent describes the idea. The first video below gives a good overview of the contraption, which consists of an “extruder” mounted on the end of a counterweighted boom, the length of which determines the radius of the circular structure produced. The boom swivels on a central mast, and is cranked up manually for each course extruded. The business end has a small hopper for what appears to be an exceptionally dry concrete or mortar mix. The hopper has a bunch of cam-driven spades that drive down into the material to push it out of the hopper; the mix is constrained between two rotating disks that trowel the sides smooth and drive the extruder forward.

The device has a ravenous appetite for material, as witnessed by the hustle the workers show keeping the machine fed. Window and door openings are handled with a little manual work, and the openings are topped with lintels to support the concrete. Clever tools are used to cut pockets for roof rafters, and the finished structure, complete with faux crenellations and a coat of stucco, looks pretty decent.

Continue reading “Retrotechtacular: 3D-Printed Buildings, 1930s Style” →

an up-close of the PCB hotplate

Using A PCB To Reflow PCBs – Take 2!

October 6, 2021 by 29 Comments

It’s not too hard to make your electronics project get warm. Design your traces too small, accidentally short the battery inputs together, maybe reverse the voltage going to your MCU. We’ve all cooked a part or two over the years. But what about making a PCB that gets hot on purpose? That’s exactly what [Carl Bugeja] did in his second revision of a PCB hot plate, designed to reflow other PCBs.

[Carl’s] first attempt at making a hot plate yielded lukewarm results. The board, which was a single snaking trace on the top of an aluminum substrate, did heat up as it was supposed to. However, the thin substrate led to the hot plate massively warping as it heated up, reducing the contact against the boards being soldered. On top of that, the resistance was much greater than expected, resulting in much lower heat output.

The new revision of the board is on a thicker substrate with much thicker traces, reducing the resistance from 36 ohms on the previous design to just 1 ohm. The thicker substrate, paired with a newer design with fewer slots, made for a much sturdier surface that did not bend as it was heated.

Continue reading “Using A PCB To Reflow PCBs – Take 2!” →

Dave went from a passive decoy to a high-speed boating machine.

Dave The Drive-able Duck Does Donuts

October 6, 2021 by 9 Comments

[Hey Jude] is tired of the machismo dripping from most modern electronic toys, especially stuff like monster trucks and police/military sets. He grew up on weird stuff, not aggression, and wanted to share the experience of kit-bashing a new toy together alongside his son.

This is essentially an R/C boat stuffed into a decoy duck, but there’s more to it than that. After removing the ballast that made him stay upright, [Hey Jude] performed plastic surgery on both sides of Dave the duck, creating a boat-shaped hole in the bottom, and a hinged bonnet out of the top which serves as an access panel for the boat’s innards. Everything is sealed up with Sugru, though you could probably use caulk or even hot glue (if you wanted something more temporary and less expensive).

The smartest bit has to be the loop on Dave’s back — this makes it easy to lower him into a pond from a footbridge, or rescue him if he stalls in the middle of the water. Check out the footage of Dave’s maiden voyage after the break.

Remote control of things will never get old. Do you have an old Nintendo Zapper lying around? Why not make it do your home automation bidding?

Continue reading “Dave The Drive-able Duck Does Donuts” →