Author: Navarre Bartz

327 Articles

A quadcopter with a clear, U-shaped shield up front and red propellers navigates between a close stand of moss-covered trees.

Echolocation For Drones

July 20, 2026 by 7 Comments

Bats are remarkable creatures, able to fly at night or inside the confines of caves without light to guide their way. A team of researchers at Worcester Polytechnic Institute (WPI) has determined how to use low power ultrasonic sensors to guide drones in obscured environments.

While radar, lidar, and GPS are all great for navigation and sensing, they can run into issues when light is obscured or can take too much power to be practical for the limited battery life of a drone. The researchers found that a dual sonar array could be used to implement a much lower power sensing system for a drone that performs well in environments that would stymie a computer vision system.

A shield placed behind the array cuts down on the sound of the propellers that would otherwise drown out the signal, and further signal analysis via a neural net separates the echoes of objects in front of the drone from the background. The prototype could navigate in various simulated environments like forests, smoke, and snow. It looks like it even got a chance to go for a flight in the actual woods. All the code and hardware designs are Open Source, so have at it!

We’ve covered mosquito-inspired drone sensors before, and if you want to get into echolocation yourself, apparently humans can learn to do it too.

Continue reading “Echolocation For Drones” →

A black pickup sits in front of a snow-capped mountain range in the background. It has a white camper shell with a sci-fi looking "01" emblazoned on the side in black text. An orange, wedge-shaped tent pops up above the campershell and truck roof.

A Pop-Up Truck Camper For Less

July 19, 2026 by 15 Comments

We live in a veritable Cambrian Explosion of camping options, ranging from a tarp on the ground to multi-million dollar RVs. Somewhere around the middle is the pop-up truck camper, but [Further Fabrication] wanted to build his own.

As is often the case, he saw the cool pop-up truck campers on the market, but balked at the cost. To make matters worse, the options out there weren’t really available in his country. After getting a solid set of measurements from the truck and some materials, he set to work.

The most interesting part of this build is probably the aluminum/plywood sandwich [Further Fabrication] chose for building the main structure of the camper shell. While many would’ve chosen a tubing space frame for the build, he decided to sandwich two layers of plywood around plywood beams and large rectangular aluminum tubing. These were affixed with a combination of construction adhesive and screws to create a lightweight yet sturdy enclosure.

The tent portion uses a 600-denier PVC-coated waterproof polyester fabric, sewn with nice YKK zippers, and features large windows with screens for excellent ventilation. The roof consists of two sections of aluminum composite sandwich, and the side panels were made from cutoffs of the roof material. Instead of the standard cam-lock used on most camper shells, [Further Fabrication] chose a solenoid-actuated system and more conventional grab handles.

We’ve covered campers several times, including a solar-powered RV, a truck camper that expands lengthwise rather than up, and several bike-based campers.

Continue reading “A Pop-Up Truck Camper For Less” →

A man in a black shirt with the word "Mutiny" in yellow letters next to a short set of red, orange, and yellow stripes like a 1970s truck graphics package guestures to the camera while holding a sketch of a blurple truck consisting of a tube frame cab, flat loading deck, orange seat, and a silvery front bumper.

A New Challenger Approaches The Open Source Vehicle

July 6, 2026 by 51 Comments

Cheap vehicles are thin on the ground in 2026, but [Andy Didorosi] thinks he has the answer for low-speed applications with an open source kei truck.

Still in the early design phase, [Didorosi] has an old factory in Detroit that has been home to his bus transportation business for the last several years, as well as the Sendpai kei truck project to make the world’s fastest kei truck. His vision is to make an affordable kit car truck that anyone can build in the comfort of their own garage. The current plan includes hub motors, which have so far not made it into any production EVs in the US, likely due to the problem with high unsprung weight.

Continue reading “A New Challenger Approaches The Open Source Vehicle” →

A man standing next to an RC model of an Airbus A380 aircraft. The fuselage is at elbow height and the tailfin appears to be over his head.

World’s Biggest RC A380 Is A Big Deal

June 27, 2026 by 15 Comments

RC planes are a lot of fun, and the bigger the better! [Ramy RC] has built the world’s biggest RC A380.

At 29 ft (8.83 m) long, with a 32 foot (9.75 m) wingspan, and weighing 800 lb (362 kg), this 1/8 scale jumbo jet is not your typical model. The fuselage is built from CNC cut EPS foam layed up with fiberglass on the outside and carbon fiber inside. The wings have a combination of carbon, aluminum, foam, and wood components to handle the aerodynamic loads.

The attention to detail is wild. Instead of painting the windows, each one is an actual hole in the plane with a 3D printed window frame and acrylic window. You can actually see one falling out of the plane in the video below. An Airbus mechanic in the comments even notes the landing gear door order of operations are identical to the real thing.

If [Ramy] looks familiar, perhaps you remember his previous A380 build? Much like the 747, the full size A380 is no longer in production, but they can run on cooking oil while they’re still flying.

Continue reading “World’s Biggest RC A380 Is A Big Deal” →

A white man in a dark t-shirt and glasses stands next to a pegboard. On the pegboard is a cylindrical wooden bird house with a small piece of metal roof attached to the top. A set of heat lamps are suspended above and give the image a reddish-orange glow. 87˚F is in white text in the lower left corner.

Do Metal Roofs Turn A Bird House Into An Oven?

June 27, 2026 by 34 Comments

Birdhouses can be a great way to help out nesting birds in your area, but they can be a bit intensive to make. As part of a 500 birdhouse marathon, [Of Human and Nature] decided to test whether a metal roof would be safe or turn the birdhouse into an oven.

Most DIY birdhouses are made of wood to encourage cavity nesting species that would naturally find a hole in a tree to use the house. Unfortunately, an unprotected chunk of wood will deteriorate much faster than a whole tree full of holes might. A metal roof reduces the exposure to the elements, but does it make the box too hot?

[Of Human and Nature] heeded concerns from commenters and actually tested his hypothesis with a simple set of thermocouples, a heat lamp, and an assembled birdhouse. While the metal roof was held at 70˚C for four hours, the inside of the house stayed in the mid 20˚C range thanks to the separation between the roof and the actual box which allows air to flow between the two.

Maybe a metal roof could help you house your homing pigeons as well? If you want to spread the mesh with your birdhouse instead, how about a solar panel roof with a LoRa node?

Continue reading “Do Metal Roofs Turn A Bird House Into An Oven?” →

A heat map of the US showing the difference in emissions between an EV and ICE or EV and PHEV by county. Rural areas, particularly in Colorado in Wyoming seem close to no difference (in blue) whereas densely-populated areas on the coasts are colored on the red end of spectrum exceeding a 70% emissions reduction over ICE vehicles.

EVs Always Beat Combustion Emissions Performance

June 23, 2026 by 155 Comments

A pervasive story is that electric vehicles (EVs or BEVs) are actually dirtier than combustion vehicles if charged by a fossil fuel-based electricity grid. A new study reaffirms others that show, at least in the US, EVs have lower lifetime emissions than an internal combustion engine (ICE) vehicle, regardless of the grid mix.

Comparing data on the mix of generation types by ZIP code using data from OpenGrid and eGRID, the researchers were able to create maps and comparisons of the efficiency of ICE, hybrid, plug-in hybrid (PHEV), and electric vehicles. If you want to compare some specific examples, there’s an interactive chart using the research data at carboncounter.com.

PHEVs can achieve 80-90% of the emissions reductions of a full EV in urban environments, but become less beneficial as distances increase or if drivers choose not to charge the battery. The researchers have extensive breakdowns of the comparisons including total cost to operate the vehicle compared with emissions if you want to look more in the paper. Emissions benefits are particularly noticeable in larger vehicle classes or with drivers who put more miles on their cars.

Although it’s unlikely to change anytime soon, they also note that if the industry trend toward larger and larger vehicles were to be reversed, emissions targets could be hit with much fewer hybrids and EVs at the current grid mix. The advantage of full EVs is that they get cleaner as the grid gets cleaner, unlike combustion vehicles that typically get worse as their emissions systems degrade.

If you’re not ready for an EV, maybe you’d like to reuse a pack for a house battery. If you’re feeling more adventurous, then maybe try out an EV conversion that still needs oil changes?