EV Charging Connectors Come In Many Shapes And Sizes

April 28, 2022 by Zoe Skyforest 69 Comments

Electric vehicles are now commonplace on our roads, and charging infrastructure is being built out across the world to serve them. It’s the electric equivalent of the gas station, and soon enough, they’re going to be everywhere.

However, it raises an interesting problem. Gas pumps simply pour a liquid into a hole, and have been largely standardized for quite some time. That’s not quite the case in the world of EV chargers, so let’s dive in and check out the current state of play.

AC, DC, Fast, or Slow?

Since becoming more mainstream over the past decade or so, EV technology has undergone rapid development. With most EVs still somewhat limited in range, automakers have developed ever-faster charging vehicles over the years to improve practicality. This has come through improvements to batteries, controller hardware, and software. Charging tech has evolved to the point where the latest EVs can now add hundreds of miles of range in under 20 minutes.

However, charging EVs at this pace requires huge amounts of power. Thus, automakers and industry groups have worked to develop new charging standards that can deliver high current to top vehicle batteries off as quickly as possible.

As a guide, a typical home outlet in the US can deliver 1.8 kW of power. It would take an excruciating 48 hours or more to charge a modern EV from a home socket like this.

In contrast, modern EV charge ports can carry anywhere from 2 kW up to 350 kW in some cases, and require highly specialized connectors to do so. Various standards have come about over the years as automakers look to pump more electricity into a vehicle at greater speed. Let’s take a look at the most common options out in the wild today. Continue reading “EV Charging Connectors Come In Many Shapes And Sizes” →

Drone Filming Chile’s Urban Bike Race Takes Some Fancy Radio Gear

April 27, 2022 by Zoe Skyforest 13 Comments

Drones have revolutionized the world of videography in perhaps the biggest way since the advent of digital hardware. They’re used to get shots that are impractical or entirely impossible to get by any other means. The [Dutch Drone Gods] specialize in such work. When it came to filming an urban mountain bike race in a dense Chilean city, they had to bust out some serious tricks.

The FPV video feed was grainy, but good enough to keep the pilot on track. The drone carried a separate second camera for capturing high-quality footage of the run.

Typically, running a drone chase cam behind a biker would require some good first-person flying skills and a quick drone. However, for the Red Bull Valparaiso Cerro Abajo urban downhill event, this alone would not be enough. The tight course winds down staircases between thick concrete walls and even through houses, presenting huge challenges to maintaining signal integrity. Without a clear video signal, the pilot can’t fly the drone without crashing.

To make this all possible, the team used a variety of techniques to help combat the uncooperative radio environment. Directional antennas were used to target different sections of the course. Additionally, a second drone was flown high above the course carrying a radio repeater, helping provide a better line-of-sight contact to the camera drone following the riders when the buildings would otherwise block the signal to the pilot.

Even with all this work, the signal was still scratchy and would cut out at some points. However, with a bit of blind faith when cutting through the worst areas, the [Dutch Drone Gods] and the [Red Bull] team were able to put together an amazing FPV drone shot shadowing [Tomas Slavik] on his run down the extremely difficult urban course.

Details on the precise hardware are scarce. However, it’s something that any experienced drone builder could probably whip up without too much trouble. The idea of using a drone-based repeater is particularly exciting, and something we’re sure could help out many pilots who find themselves operating in difficult urban environments.

We’ve seen plenty of great FPV stories over the years, from early experiments in the 1980s to fun DIY cockpit builds of today. Video after the break.

Continue reading “Drone Filming Chile’s Urban Bike Race Takes Some Fancy Radio Gear” →

Hackaday Prize 2022: Glass Tube Solar Thermionic Converters

April 27, 2022 by Zoe Skyforest 13 Comments

Typically, if you want to convert solar energy into electrical energy, you use either photovoltaic (PV) cells, or you use the sunlight to create steam to turn a turbine. Both of these methods are well-established and used regularly in both small- and grid-scale applications. However, [Nick Poole] wanted to investigate an alternative method, using thermionic converters for solar power generation.

[Nick] has been gearing up to produce various styles of vacuum tubes, and noted that the thermionic effect that makes them work could also be used to generate electricity. They are highly inefficient and produce far less power than a photovoltaic solar cell, meaning they’re not in common use. However, as [Nick] notes, unlike PV cells etched in silicon, a thermionic converter can be built with basic glassworking tools, requiring little more than a torch, a vacuum pump, and a spot welder.

Experiments with a large lens to focus sunlight onto a 6V3A diode tube showed promise. [Nick] was able to generate half a volt, albeit at a tiny current, with the design not being optimized for thermionic conversion. Further experiments involved electrically heating a pair of diode tubes, which was able to just barely light an LED at 1.7 V and a current of 7.5 uA. The conversion efficiency was a lowly 0.00012%, around 5 orders of magnitude worse than a typical PV cell.

[Nick]’s hope is that he can produce a tube designed specifically to maximize thermionic conversion for energy generation purposes. It’s likely there is some low-hanging fruit in terms of gains to be made simply by optimizing the design for this purpose, even if the technique can’t compete with other solar generation methods.

In any case, we’re eager to see what [Nick] comes up with! We love to see makers building tubes in their own home workshops.

Continue reading “Hackaday Prize 2022: Glass Tube Solar Thermionic Converters” →

The State Of Play In Solid State Batteries

April 27, 2022 by Zoe Skyforest 142 Comments

Electric vehicles are slowly but surely snatching market share from their combustion-engined forbearers. However, range and charging speed remain major sticking points for customers, and are a prime selling point for any modern EV. Battery technology is front and center when it comes to improving these numbers.

Solid-state batteries could mark a step-change in performance in these areas, and the race to get them to market is starting to heat up. Let’s take a look at the current state of play.

Continue reading “The State Of Play In Solid State Batteries” →

Building Reaction Wheels With Python And LEGO

April 27, 2022 by Zoe Skyforest 3 Comments

Reaction wheels are useful things, typically used by satellites to keep themselves oriented the right way up in space. Turning the reaction wheel creates an equal and opposite torque in the spacecraft, allowing it to point and rotate itself accurately. The same technique also works here on Earth, and [Brick Experiment Channel] decided to build one out of LEGO to control an inverted pendulum.

The initial design using a small LEGO wheel on an inverted pendulum was only able to work reliably over a 4-degree angle from the vertical. Upgrading the wheel to a larger, heavier one enabled the wheel to instead work over a 28-degree range instead.

A MPU9250 inertial measurement unit was pressed into service for control of the reaction wheel, fitted to the base of the pendulum and read by a Raspberry Pi. The Pi takes accelerometer and gyroscope readings, and then controls the motor on the pendulum with a PID controller to keep the inverted pendulum upright.

The video goes into a great deal of detail on what it takes to make the pendulum run smoothly. From changes to the control coefficients to measuring the motor’s back EMF, [Brick Experiment Channel] demonstrates everything required to make the pendulum robust to outside perturbances.

The inverted pendulum is a great way to learn about control theory, as we’ve seen time and again.

Continue reading “Building Reaction Wheels With Python And LEGO” →

Simple Photo Enlarger Makes Great Addition To Any Darkroom

April 26, 2022 by Zoe Skyforest 6 Comments

Chemical-based photography can seem like a dark art at times, but it needn’t be so. [Dan K] developed the Simple Enlarger to help spread the idea that classical photographic darkroom tools are fundamentally quite easy to understand and build.

A photographic enlarger illuminates a negative with light, and focuses this light on a sheet of photographic paper which can then be developed. [Dan’s] enlarger design is intended to be built using materials readily available from any dollar store or stationer’s shop, and can be built in just a few short hours. It’s built to work with a single film format and with a fixed size of photographic paper for simplicity’s sake.

A simple M-mount camera lens is pressed into service for the main optic, with the ex-Soviet part chosen for its easy focusing and cheap price. A small plywood box makes a decent body, and a white phosphor LED provides the light source. The final rig is designed to print 35mm negatives on to standard 8×10 paper.

If you want to get into developing your own negatives and don’t want to buy a commercial enlarger, [Dan]’s build could be just the way to go. We’ve seen some other similar builds before, too. Meanwhile, if you’ve got your own nifty darkroom hacks, be sure to drop us a line!

2022 Sci-Fi Contest: Multi-Sensor Measurement System

April 26, 2022 by Zoe Skyforest 4 Comments

Many sci-fi movies and TV shows feature hand-held devices capable of sensing all manner of wonderful things. The µ Spec Mk II from [j] is built very much in that vein, packing plenty of functionality into a handy palm-sized form factor.

An ESP32 serves as the brains of the device, hooked up to a 480×320 resolution touchscreen display. On board is a thermal camera, with 32×24 pixel resolution from an MLX90640 sensor. There’s also a 8×8 LIDAR sensor, too, and a spectral sensor that can capture all manner of interesting information about incoming light sources. This can also be used to determine the transmission coefficient or reflection coefficient of materials, if that’s something you desire. A MEMS microphone is also onboard for capturing auditory data. As a bonus, it can draw a Mandelbrot set too, just for the fun of it.

Future plans involve adding an SD card so that data captured can be stored in CSV format, as well as expanding the sensor package onboard. It’s a project that reminds us of some of the tricorder builds we’ve seen over the years. Video after the break.

Continue reading “2022 Sci-Fi Contest: Multi-Sensor Measurement System” →