Avocado-Shaped Robot Makes Its Way Through The Rainforest

February 3, 2024 by Lewin Day 12 Comments

When you think of a robot getting around, you probably think of something on wheels or tracks. Maybe you think about a bipedal walking robot, more common in science fiction than our daily lives. In any case, researchers went way outside the norm when they built an avocado-shaped robot for exploring the rainforest.

The robot is the work of doctoral students at ETH Zurich, working with the Swiss Federal Institute for Forest, Snow, and Landscape research. The design is optimized for navigating the canopy of the rainforest, where a lot of the action is. Traditional methods of locomotion are largely useless up high in the trees, so another method was needed.

The avocado robot is instead tethered to a cable which is affixed to a high branch on a tree, or even potentially a drone flying above. The robot then uses a winch to move up and down as needed. A pair of ducted fans built into the body provide the thrust necessary to rotate and pivot around branches or other obstacles as it descends. It also packs a camera onboard to help it navigate the environment autonomously.

It’s an oddball design, but it’s easy to see how this design makes sense for navigating the difficult environment of a dense forest canopy. Sometimes, intractable problems require creative solutions. Continue reading “Avocado-Shaped Robot Makes Its Way Through The Rainforest” →

Go Fly A Kite

November 13, 2022 by Bryan Cockfield 17 Comments

Harvesting energy from the wind has been a commercially viable way of generating clean energy for around three decades now. Wind turbines are a reliable, proven technology but they do have some downsides, one of which is that since there’s more wind higher above the ground this usually means tall, expensive towers. There is a way around this problem, though, which is using kites to generate energy instead of a fixed turbine.

While kite generators aren’t a new idea, [Benjamin] has been working on this kite generator which has a number of improvements over existing kite generators. Like other kite generators, this one uses a tether to spin a generator which is located on the ground. But while this is similar to other kite systems, this prototype has a much simpler design and sweeps a much larger area while in flight. It also has an autopilot with multiple independent steering systems, which [Benjamin] says will allow it to stay in flight for months at a time provided there is enough wind. If there isn’t, it can land reliably, and launching it is relatively fast and simple as well.

While kites do have some obvious downsides compared to fixed turbines including a single point of failure at the tether and a large amount of cleared area to operate, they have plenty of advantages as well. They’re smaller, simpler, require no complicated yaw system, and can be easily maintained on the ground. In fact, it’s possible to build very simple kite generators out of nothing more than a hobby kite and some readily-available electrical components.

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Pinning Tails On Satellites To Help Prevent Space Junk

September 13, 2021 by Tom Nardi 32 Comments

Low Earth orbit was already relatively crowded when only the big players were launching satellites, but as access to space has gotten cheaper, more and more pieces of hardware have started whizzing around overhead. SpaceX alone has launched nearly 1,800 individual satellites as part of its Starlink network since 2019, and could loft as many as 40,000 more in the coming decades. They aren’t alone, either. While their ambitions might not be nearly as grand, companies such as Amazon and Samsung have announced plans to create satellite “mega-constellations” of their own in the near future.

At least on paper, there’s plenty of room for everyone. But what about when things go wrong? Should a satellite fail and become unresponsive, it’s no longer able to maneuver its way out of close calls with other objects in orbit. This is an especially troubling scenario as not everything in orbit around the Earth has the ability to move itself in the first place. Should two of these uncontrollable objects find themselves on a collision course, there’s nothing we can do on the ground but watch and hope for the best. The resulting hypervelocity impact can send shrapnel and debris flying for hundreds or even thousands of kilometers in all three dimensions, creating an extremely hazardous situation for other vehicles.

One way to mitigate the problem is to design satellites in such a way that they will quickly reenter the Earth’s atmosphere and burn up at the end of their mission. Ideally, the deorbit procedure could even activate automatically if the vehicle became unresponsive or suffered some serious malfunction. Naturally, to foster as wide adoption as possible, such a system would have to be cheap, lightweight, simple to integrate into arbitrary spacecraft designs, and as reliable as possible. A tall order, to be sure.

But perhaps not an impossible one. Boeing subsidiary Millennium Space Systems recently announced it had successfully deployed a promising deorbiting device developed by Tethers Unlimited. Known as the Terminator Tape, the compact unit is designed to rapidly slow down an orbiting satellite by increasing the amount of drag it experiences in the wispy upper atmosphere.

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Sky Anchor Puts Radios Up High, No Tower Needed

July 3, 2020 by Dan Maloney 65 Comments

When it comes to radio communications on the VHF bands and above, there’s no substitute for elevation. The higher you get your antenna, the farther your signal will get out. That’s why mountaintops are crowded with everything from public service radios to amateur repeaters, and it’s the reason behind the “big stick” antennas for TV and radio stations.

But getting space on a hilltop site is often difficult, and putting up a tower is always expensive. Those are the problems that the Sky Anchor, an antenna-carrying drone, aims to address. The project by [Josh Starnes] goes beyond what a typical drone can do. Rather than relying on GPS for station keeping, [Josh] plans a down-looking camera so that machine vision can keep the drone locked over its launch site. To achieve unlimited flight time, he’s planning to supply power over a tether. He predicts a 100′ to 200′ (30 m to 60 m) working range with a heavy-lift octocopter. A fiberoptic line will join the bundle and allow a MIMO access point to be taken aloft, to provide wide-area Internet access. Radio payloads could be anything from SDR-based transceivers to amateur repeaters; if the station-keeping is good enough, microwave links could even be feasible.

Sky Anchor sounds like a great idea that could have applications in disaster relief and humanitarian aid situations. We’re looking forward to seeing how [Josh] develops it. In the meantime, what’s your world-changing idea? If you’ve got one, we’d love to see it entered in the 2020 Hackaday Prize.

The Options For Low Cost ROV Tethers

January 27, 2020 by Richard Baguley 22 Comments

Wireless connections are cool and all, but sometimes you just need a bit of copper. This interesting article on SV Seeker discusses the various ways of making a tether for a remotely operated vehicle (ROV). They experimented with a number of different cables, including gel-filled Cat 5 designed for burial and wrapping the cable in polypropylene rope to keep it protected and buoyant. They also looked at using a single core solid coax cable with an Ethernet to coax converter on either end wrapped in stretch webbing. The upside of using coax would be the length: it can handle over a mile of cable, which should be more than enough for this project. The downside is that they found that the coax stretches under strain, messing with the signal.

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One Small Step For A Space Elevator

September 14, 2018 by Tom Nardi 149 Comments

Space elevators belong to that class of technology that we all want to see become a reality within our lifetimes, but deep-down doubt we’ll ever get to witness firsthand. Like cold fusion, or faster than light travel, we understand the principles that should make these concepts possible, but they’re so far beyond our technical understanding that they might as well be fantasy.

Except, maybe not. When Japan Aerospace Exploration Agency (JAXA) launches their seventh Kounotori H-II Transfer Vehicle towards the International Space Station, riding along with the experiments and supplies for the astronauts, will be a very special pair of CubeSats. They make up the world’s first practical test of space elevator technology, and with any luck, will be one of many small steps that precedes the giant leap which access to space at a fraction of the cost will be.

Of course, they won’t be testing a fully functional space elevator; even the most aggressive of timelines put us a few decades out from that. This will simply be a small scale test of some of the concepts that are central to building a space elevator, as we need to learn to crawl before we can walk. But even if we aren’t around to see the first practical space elevator make it to the top, at least we can say we were there on the ground floor.

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DIY Submersible Aims For Low Cost, Ease Of Operation

May 26, 2018 by Dan Maloney 4 Comments

If you’re like us, a body of water is a source of wonder and awe. The wonder comes from imagining what lies hidden below the surface, and the awe is from the fear of trying to find out and becoming one of those submerged objects on a permanent basis. So if you want to explore the depths in relative comfort and safety, a DIY remotely operated underwater vehicle might be the thing you need to build.

Most ROV builds these days seem to follow more or less similar designs, which is probably because they all share project goals similar to those of [dcolemans]: build something to take a look around under the water, make it easy to operate, and don’t spend a ton of money. To achieve that, he used 1/2″ PVC pipe and fittings to build the frame and painted it yellow for visibility. A dry tube for the electronics was fashioned from 4″ ABS pipe. The positive buoyancy provided by the dry tube is almost canceled out by the water flooding the frame through weep holes and the lead shot ballast stored in the landing skids. Propulsion is provided by bilge pump cartridges with 3D-printed ducted propellers. A nice touch is a separate topside control box with a screen for the ROV’s camera that talks to a regular RC controller, along with simplified controls and automatic station keeping. Check out the recent swimming pool test in the video below.

There’s a lot going on under the sea, and plenty of ways to explore it. You could deploy sensors shaped like clams, zap underwater lice with lasers, or even glide your way to a Hackaday Prize.

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