Historically, nature has used trees to turn carbon dioxide back into oxygen for use by living creatures. The trees play a vital role in the carbon cycle, and have done so for millennia. Recently, humans have thrown things off a bit by getting rid of lots of trees and digging up a lot more carbon.
While great efforts are underway to replenish the world’s tree stocks, Belgrade has gone in a different direction, creating artificial “liquid trees” to capture carbon dioxide instead. This has spawned wild cries of dystopia and that the devices are an affront to nature. Let’s sidestep the hysteria and look at what’s actually going on.
Continue reading “The Liquid Trees Of Belgrade: The Facts Behind The Furore”
Harmful Algal Blooms (HABs) can have negative consequences for both marine life and human health, so it can be helpful to have early warning of when they’re on the way. Algal blooms deep below the surface can be especially difficult to detect, which is why [kutluhan_aktar] built an AI-assisted algal bloom detector.
After taking images of deep algal blooms with a boroscope, [kutluhan_aktar] trained a machine learning algorithm on them so a Raspberry Pi 4 could recognize future occurrences. For additional water quality information, the device also has an Arduino Nano connected to pH, TDS (total dissolved solids), and water temperature sensors which then are fed to the Pi via a serial connection. Once a potential bloom is spotted, the user can be notified via WhatsApp and appropriate measures taken.
If you’re looking for more environmental sensing hacks, check out the OpenCTD, this swarm of autonomous boats, or this drone buoy riding the Gulf Stream.
What’s the size of an AA battery and can run an ARM Cortex M0+ for six months? Well… probably an AA battery, but obviously, that wouldn’t be worth mentioning. But researchers at Cambridge have built a cell of blue-green algae that can do the job.
As you might expect, the algae need light, since they generate energy through photosynthesis. However, unlike conventional solar cells, the algae continue to produce energy in the dark at least for a while. Presumably, the algae store energy during the day and release it at night to survive naturally-occurring periods of darkness.
Generating power from photosynthesis isn’t a new idea since photosynthesis releases electrons. A typical cell has gold electrodes and a proton exchange membrane of some kind. You can see a video from Cambridge below about generating electricity from photosynthesis. Keep in mind, of course, that the Cortex M0+ is capable of very low power operation. Don’t look for that algae-powered spot welder anytime soon.
People tend to get fixated on electricity as energy, but there are other ways to harness photosynthesis. For example, we’ve seen algae fueling a chicken hole in the past. Not to mention we’ve seen algae used to power a robot in a novel and non-electrical way.
Continue reading “Running ARM Chips On Algae Power”
[Cody] of Cody’sLab has been bit by what he describes as the algae growing bug. We at Hackaday didn’t know that was a disease floating around, but we’ll admit that we’re not surprised after the last few years. So not content to stick to the small-time algae farms, [Cody] decided to scale up and build a whole algae panel.
Now, why would you want to grow algae? There are edible varieties of algae, you can extract oils from it, and most importantly, it can be pumped around in liquid form. To top it off, all it needs is just sunlight, carbon dioxide, and a few minerals to grow. Unlike those other complicated land-based organisms that use photosynthesis, algae don’t need to build any structure to hold themselves up or collect sunlight; it floats.
The real goal of the algae is to build a system known as “Chicken Hole.” The basic idea is to have a self-sufficient system. The algae feed the insects, the insects feed the chickens, and so on up the chain until it reaches [Cody]. While glass would make an ideal material for the algae tubes, plastic soda bottles seem like a decent proxy for a prototype and are much cheaper. He connected around 100 half-liter bottles to form long tubes and a PVC distribution system. The algae needs to be pumped into an insulated container to prevent it from freezing at night. At first, a simple timer outlet controlled the pump to only run during the day, draining it via gravity at night. However, the algae can’t heat up enough when running on cloudy, cold winter days, and it cools off. A solar panel and a temperature sensor form the logic for the pump, with a minimum temperature and sunlight needed to run.
[Cody] mentions that he can expect around 10 grams of algae per day on a panel this size in the winter. He’s going to need quite a few more if he’s going to scale up properly. Perhaps in the future, we’ll see panels growing algae robots? Video after the break.
Continue reading “Move Aside Solar, We’re Installing An Algae Panel”
When you think of a robot, you probably don’t think of a ball of underwater algae. But a team of university researchers used a 3D-printed exoskeleton and a ball of marimo algae to produce a moving underwater sensor platform. It is really at a proof-of-concept stage, but it seems as though it would be possible to make practical use of the technology.
Marimo are relatively rare balls of algae that occur in some parts of the world. A robot powered by algae runs on sunlight and could be electromagnetically quiet.
Continue reading “That’s No Moon… It’s An Algae Robot”
There’s a famous scene in the movie version of Frankenstein — but not in the book — where the doctor exclaims: “It’s alive!” We wonder if researchers at TU Delft had the same experience after printing living structures using algae. Of course, they aren’t creating life or even reanimating it. They are simply depositing living cells in artificial structures using a bio-compatible substrate. According to the paper, the living cells or bio ink can build up layers in a 3D printing fashion and the structures are “self-standing.”
There are some advantages, for example that the algae get their energy from sunlight. Of course they also have to eat, so unless you provide some snacks, your print will die off in about 3 days.
Continue reading “Printer Uses Algae To Print Live Structures”
What are single-celled organisms good for, you may wonder? Science has found a wonderful new use for one of them — restoring partial sight to people with inherited forms of blindness. More specifically, they took a gene from algae that responds to light and moves toward it in order to replace dead or defective photo-receptor cells that lie between the human pupil and the optic nerve.
When light enters the eye, it triggers photo-receptor cells that in turn send signals to nerve cells called ganglions. These add information about motion and send the complete picture to the brain via the optic nerve. The researchers basically hacked the ganglion cells and turned them into photo-receptors. First they used a virus to get light-sensing molecules called chrimson into one of the retinas of the lone volunteer they’d managed to train before the pandemic. He’d been wearing the goggles out on walks and told them he could see the stripes of the crosswalk.
They were able to get him into the lab in summer 2020, where he donned a pair of goggles that register light changes and send amber light into the eye whenever that happens. He also wore a cap full of electrodes so the researchers could see what parts of his brain lit up when the goggles do their thing. With the goggles on and ready to fire, the man was able to distinguish whether a black cup was in front of him, and was even able to count multiple cups correctly most of the time. Although this is not a full restoration of vision, it’s an excellent development in that direction, and we’re excited to see where it goes.
In the future, the researchers hope to slim down the goggles into something more fashionable. Combine them with these camera-enabled shoes, and accessibility goes way up.
Thanks for the tip, [foamyguy]!