Pedal Faster! I Need To Join A Conference Call!

It is rare to find a car these days without some mechanism for charging a cell phone. After all, phones need charging all the time and we spend a lot of time in our cars. But what if you spend a lot of time on your bike? Five teens from Lynchburg, Virginia decided to build something to charge their phones from pedal power.

This isn’t a new idea, of course. Your alternator is charging your phone in your car, and bikes have had alternators connected to them for lights and other purposes. According to the team, you need to pedal about 4 miles per hour to get enough voltage to charge the phone. You can go faster though, because the circuit has a regulator. We especially liked how they determined the speed versus the voltage using a tachometer and an electric drill. We also liked the 3D printed parts such as the handlebar mount that you could probably repurpose for other things.

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The Basics Of SCRs

Although the silicon controlled rectifier or SCR has been around since 1957, it doesn’t get nearly the love an ordinary transistor does. That’s a shame because they are quite handy when it comes to controlling AC and DC voltages in things such as lamp dimmers, motor speed controllers, and even soldering iron temperature controllers. [Lewis Loflin] has a short video introduction that will help you get started with these devices.

One of the interesting properties of the device is that once you turn it on it will stay on until you do something specific to turn it back off — sort of, [Lewis] explains it in the video.

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Hackaday Links: July 14, 2019

The M5Stack is a plastic box loaded up with an ESP32, a display, some pin headers, and a few buttons. Why does this exist? It’s a platform of sorts, and we’ve seen people adding LoRa to the M5Stack as well as thermal cameras. Hot from random online retailers is the M5Stick, a smaller version of the ~Stack that still has a screen, still has pin headers, and still has an ESP32. It’s a new development platform that’s using a USB C plug (hot trends 2019), and it still has all the features of an ESP32.

Ever wonder how they put designs on skateboard decks, or graphic designs on luggage? That would be a UV printer — it’s basically an inkjet that uses UV-curing ink, but the print head has a Z axis, and the bed is usually huge. [Scotty] of Strange Parts recently took a look at a factory that makes UV printers. Yeah, there’s a lot of wiring that goes into these machines, and yeah, you can do a lot with them. Remember: the cheapest UV printers are about $3k, and yeah, you can print designs on PCBs with them.

Virgin Orbit is the Branson-branded take on the Stratolaunch; this is a rocket that uses a single 747 to loft a small rocket into the stratosphere and send it off into a sun-synchronous orbit. This week, Virgin Orbit has completed drop tests to characterize how the rocket falls away from the 747. This is also called ‘a bombing run’, and we could have used a few GoPros on the rocket itself.

Last weekend was ‘LeHack’, a French hacker/infosec conference. There was a coffee vending machine there, complete with touch screen and an offer to pay via your smartphone with an app. You know what happened. It turns out, you can take over all the accounts using the app. You can also brute force the user’s pins. Lesson learned? Why the hell does a coffee machine need an app?

The New Pallet Wood! First off, don’t make anything out of pallet wood unless you know what you’re doing; there’s some nasty chemicals in pallet wood. That said, you can make a fortune with pallet wood furniture on Etsy, and that’s doubly true if you make a pallet wood resin river table. This is the new pallet wood. Hollow core doors are easy to disassemble with a table saw, and provide two large sheets of plywood, and enough sticks to make a frame for something. What can you do with all this wood? Build a guitar, of course.

The Proof Is In The Box

Making bread dough is simple — it’s just flour and water, with some salt and yeast if you want to make things easy on yourself. Turning that dough into bread is another matter entirely. You need to punch that dough down, you need to let it rise, and you need to knead it again. At home, you’re probably content with letting the dough rise on the kitchen counter, but there’s a reason your home loaf doesn’t taste like what you would get at a good bakery. A bakery has a proofer, or a box that lets dough rise at a temperature that would be uncomfortable for humans, but perfect for yeast.

The leavening cell is a DIY proofing box that keeps dough at a steady 26° C to 28° C, the perfect temperature for making bread, pizza dough, and even yogurts. [vittorio] made this and the results look great.

The design of this build is simple enough and made out of 20×20 aluminum profiles shaped into a cubic frame. The outside of this box is 6mm thick wooden panels coated on the inside with a heat-reflective insulating mesh. Inside of that is a frame of metal mesh to which a six-meter long cable heating element is attached. This heating element is controlled via a thermostat with a probe temperature sensor on a timer. No, it’s not very complicated but the entire idea of a proofer is to have a slightly warm box.

You can check out the promo video for the Leavening Cell below.

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Homekit Compatible Sonoff Firmware Without A Bridge

Generally speaking, home automation isn’t as cheap or as easy as most people would like. There are too many incompatible protocols, and more often than not, getting everything talking requires you to begrudgingly sign up for some “cloud” service that you didn’t ask for. If you’re an Apple aficionado, there can be even more hoops to jump through; getting your unsupported smart home devices working with that Cupertino designed ecosystem often involves running your own HomeKit bridge.

To try and simplify things, [Michele Gruppioni] has developed a firmware for the ubiquitous Sonoff WIFI Smart Switch that allows it to speak native HomeKit. No more using a Raspberry Pi to act as a mediator between your fancy Apple hardware and that stack of $4 Sonoff’s from AliExpress, they can now talk to each other directly. In the video after the break you can see that the iPad identifies the switch as unofficial device, but since it’s compliant with the HomeKit API, that doesn’t prevent them from talking to each other.

Not only will this MIT licensed firmware get your Sonoff Basic, Sonoff Slampher, or Sonoff S26 talking with your Apple gadgets, but it also provides a web interface and REST API so it retains compatibility with whatever else you might be running in your home automation setup. So while the more pedestrian users of your system might be turning the porch light on with their iPhones, you can still fire it up with a Bash script as nature intended.

Of course, if you don’t mind adding a Raspberry Pi bridge to the growing collection of devices on your network, we’ve got plenty of other HomeKit-enabled projects for you to take a look at.

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A Power Bank For Soldering On The Go

If you have a portable gadget, the chances are you’ve probably used power banks before. What few could have predicted when these portable battery packs first started cropping up is that they would one day be used to power soldering irons. Dissatisfied with the options currently available on the market, [Franci] writes in with his own power bank specifically designed for use with his TS80 portable soldering iron.

The electronics side of this build is simple and easy to replicate, with 4 18650 Li-ion cells standard to most high-capacity power banks and an off-the-shelf Fast Charge module serving as the brains of the operation. The beauty of this project however lies in the design of the actual case, completely custom-made from scratch to be 3d printed.

Unlike most power banks, where the outputs stick out to the side and leave the connectors prone to being bumped and damaged, [Franci] engineered his case so the ports are stacked on top and facing inwards. That way, USB plugs are contained within the footprint of the power bank’s body, and therefore protected from bending or snapping off in the socket. He also gracefully provides all instructions needed to make your own, including a wiring guide and a reminder about safety when dealing with battery packs.

If you’re unfamiliar with the TS80 soldering iron, we’ve featured the younger sibling of the TS100 in a previous post. And if you think this power bank is too simple for you, don’t worry, we’ve got you covered.

LEGO-Based Robot Arm With Motion Planning

Robotic arms have found all manner of applications in industry. Whether its welding cars, painting cars, or installing dashboards in cars, robotic arms can definitely do the job. However, you don’t need to be a major automaker to experiment with the technology. You can build your own, complete with proper motion planning, thanks to Arduino and ROS.

Motion planning is important, as it makes working with the robotic arm much easier. Rather than having to manually specify the rotation of each and every joint for every desired movement, instead mathematics is used to figure everything out. End effectors can be moved, and software will figure out the necessary motions required to achieve the end results. This functionality is baked into Robot Operating System (ROS) and proves useful to this project.

The construction of this particular arm is impressive in its simplicity, too. It has 7 degrees of freedom, which is plenty to play with. The arm is built out of LEGO Technic components, which are attached to the servos with the addition of some 3D printed components. It’s a smart and simple way to integrate the servos into the LEGO world, and we’re surprised we don’t see this more often.

Robotic arms remain an area of active research; there are even efforts to allow them to self-correct in the event of damage. Video after the break.

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