Homekit Compatible Sonoff Firmware Without A Bridge

July 14, 2019 by 38 Comments

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

July 14, 2019 by 15 Comments

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

July 14, 2019 by 1 Comment

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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The Demise Of The Password

July 14, 2019 by 73 Comments

Although we hackers will sometimes deliberately throw away our passwords and then try and hack our own phones / WIFI systems for self amusement, for many people including the actual inventor of the password, Fernardo “Corby” Corbató (1926-2019), passwords have become extremely burdensome and dis-functional.

Sadly, Fernando (according to the internet) died on July 12th, and equally sadly, part of his legacy was the ordeal of his “having a three-page crib sheet to stay on top of his own 150+ passwords”.

We’re all used to being badgered by websites to use complex passwords with a minimum length and a minimum number of upper case characters, lower case characters, numerical digits and non alphanumeric characters AND being told at the workplace to use different passwords than at other places AND to being told to change our passwords regularly. The fact that somebody like Fernando had 150 passwords is not surprising.

However, there is some hope, as according to Alex Weinert of Microsoft, in his recent synopsis, “When it comes to composition and length, your password (mostly) doesn’t matter”. This may well sound counter-intuitive but Microsofts’s own research suggests that inter-webs gurus should focus more on “multi-factor authentication (MFA), or great threat detection” rather than badgering the user.

The research goes into quite a bit of detail about passwords and concludes that the biggest threat to password security is when criminals obtain data from insecure ‘breached’ sites, in which case it would not matter if your word was written in hieroglyphics, it would be of no consequence at all. Another interesting conclusion was that by making passwords so intractable this encouraged people such as Fernando himself to write them all down, only for someone to rummage through their office desk (technically known as ‘dumpster diving’) and copy them.

Maybe the end of the password will now swiftly be upon us as technology enables biometrics such as ocular based identifications to be more widely used, but then again we’ve all watched those films where the protagonist scoops the eyeball out of a person’s skull to gain entry to a secure area.

It’s easy to get carried away about passwords and security hype, but it should not be forgotten that Fernardo Corbató was an eminent computer scientist who pioneered ‘Time sharing’ on computers, as detailed in this Hackaday article: Retrotectacular: Time Sharing.

Isomorphic Keyboards With CV Out

July 13, 2019 by 6 Comments

A piano keyboard can be much more than a linear row of white keys and black keys. Over the history of the keyboard, different arrangement have been made, and in the late 19th century, the Janko keyboard was developed. This keyboard that was a series of buttons laid out on a hexagonal grid. The idea being that every scale in every key is fingered the same. Chords with large intervals are easier. It also looks cool.

To date, making a MIDI Janko keyboard (with CV out) was an exercise in buying a lot of buttons and programming a microcontroller. But this 3D print from [TomsJensen] adapts what is probably the most popular MIDI keyboard in production to a Janko layout.

We have seen something like this before with [John Moriarty] building a system that adapts a standard piano keyboard and any full-size MIDI controller into an isomorphic keyboard. However, if you want to play with modular synths you need a keyboard with CV out, the cheapest and most popular being the Arturia Keystep. That’s a smaller keyboard and requires a complete redesign.

This project is up on OnShape with the files up on Thingiverse should you want to print your own. Sure, it’s just a small modification to an already popular MIDI keyboard, but if you’ve got some plastic sitting around it would be great to try out.

Fourier Explained: [3Blue1Brown] Style!

July 13, 2019 by 12 Comments

If you ask most people to explain the Fourier series they will tell you how you can decompose any particular wave into a sum of sine waves. We’ve used that explanation before ourselves, and it is not incorrect. In fact, it is how Fourier first worked out his famous series. However, it is only part of the story and master video maker [3Blue1Brown] explains the story in his usual entertaining and informative way. You can see the video below.

Paradoxically, [3Blue1Brown] asserts that it is easier to understand the series by thinking of functions with complex number outputs producing rotating vectors in a two-dimensional space. If you watch the video, you’ll see it is an easier way to work it out and it also lets you draw very cool pictures.

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A Lot Of Volts For Not A Lot

July 13, 2019 by 23 Comments

There was a time when high voltage in electronic devices was commonplace, and projects driving some form of vacuum or ionisation tube simply had to make use of a mains transformer from a handy tube radio or similar. In 2019 we don’t often have the need for more than a few volts, so when a Geiger–Müller tube needs a bit of juice, we’re stumped. [David Christensen] approached this problem by creating his own inverter, which can produce up to 1 kV from a 12 V supply.

Instead of opting for a flyback supply he’s taken a traditional step-up approach, winding his own transformer on a ferrite core. It has a centre-tapped primary which he drives in push-pull with a couple of MOSFETS, and on its secondary is a voltage multiplier chain. The MOSFETs take their drive at between 25 kHz and 50 kHz from a 555 timer circuit, and there is no feedback circuit.

It’s fair to say that this is a somewhat hair-raising circuit, particularly as he claims that it is capable of delivering that 1 kV at 20 W. It’s usual for high-voltage supplies driving very high impedance loads to incorporate a set of high-value resistors on their outputs to increase their internal impedance such that their danger is reduced. We’d thus exercise extreme care around this device, though we can see a lot of value in his description of the transformer winding.

We can’t criticise this circuit too much though, because some of us have been known to produce far hackier high voltage PSUs.