Many productive hackers bleed a dark ochre. The prevailing theory among a certain group of commenters is that they’re full of it, but it’s actually a healthy sign of a low blood content in the healthy hacker’s coffee stream. [Bharath] is among those who enjoy the caffeinated bean juice on a daily basis. However, he’d suffer from a terrible condition known as cold coffee. To combat this, he built an app-enabled, wirelessly chargeable, self-heating coffee mug.
We know that most hackers don’t start off planning to build objects with ridiculous feature lists, it just happens. Is there an alternate Murphy’s law for this? Any feature that can be added will? The project started off as some low ohm resistors attached to a rechargeable power bank. A insulated flask with a removable inner stainless steel lining was chosen. The resistors were fixed to the outside with a thermal epoxy.
However, how do we control the resistors? We don’t want to burn through our battery right away (which could end up more literally than one would like), so [Bharath] added a Linkit One microcontroller from Seeed Studio. With all this power at his disposal, it was natural to add Bluetooth, a temperature sensor, and app control to the cup.
After getting it all together, he realized that while the insides were perfectly isolated from the liquids held in the flask under normal use, the hole he’d have to cut to connect to the charging circuit would provide an unacceptable ingress point for water. To combat this he added the wireless charging functionality.
With his flask in hand, we’re sure the mood boost from not having to slog through the dregs of a cold container of coffee will produce a measureable improvement in productivity. Video after the break.
The latest version (1.3) of everyone’s favorite $5 computer now sports a frequently requested feature: a camera connector. The Pi Zero will now use the same economical camera modules available for the full-sized Raspberry Pi units.
The price of the Pi Zero is unchanged at $5, but there is a small catch. While the Raspberry Pi camera modules themselves will work just fine on the Pi Zero, the usual camera cable they come with will not. The Pi Zero’s camera cable connector is a little smaller than the ones on the full-grown Pi, so it needs a special cable to interface the camera modules to the slightly smaller connector found on the Pi Zero.
This should be good news. The new connector has appeared because another production run is ramping up. Logic points to greater availability of the $5 wonder board, but we’re still not holding our breath.
There’s a car race going on right now, but it’s not on any sort of race track. There’s a number of companies vying to get their prototype on the road first. [Anurag] has already completed the task, however, except his car and road are functional models.
While his car isn’t quite as involved as the Google self driving car, and it doesn’t have to deal with pedestrians and other active obstacles, it does use a computer and various sensors to make decisions about how to drive. A Raspberry Pi 2 takes the wheel in this build, taking input from a Pi camera and an ultrasonic distance sensor. The Pi communicates to another computer over WiFi, where a neural network operates to make decisions about how to drive the car. It also makes decisions based on a database of pictures of the track, so it has a point of reference to go by.
The video of the car in action is worth a look. It’s not perfect, but it’s quite an accomplishment for this type of project. The possibility that self-driving car models could drive around model sets like model railroad hobbyists create is intriguing. Of course, this isn’t [Anurag]’s first lap around the block. He’s already been featured for building a car that can drive based on hand gestures. We’re looking forward to when he can collide with model busses.
The Raspberry Pi was made to be inexpensive with an eye toward putting them into schools. But what about programs targeted at teaching embedded programming? There are plenty of fiscally-starved schools all over the world, and it isn’t uncommon for teachers to buy supplies out of their own pockets. What could you do with a board that cost just one dollar?
That’s the idea behind the team promoting the “One Dollar Board” (we don’t know why they didn’t call it a buck board). The idea is to produce a Creative Commons design for a simple microcontroller board that only costs a dollar. You can see a video about the project, below.
If you’ve had a child in the last few decades, you’ve had a choice to make: if you want to know the sex of the baby ahead of time. With ultrasound you can find out or–popular these days–you can have the result sealed and have a baker create a reveal cake. Apparently, researchers at the Dresden University of Technology and the University of Leipzig wanted to do the same trick with unborn chickens.
You might wonder why anyone cares (we did). Apparently, chickens that are bred for egg laying don’t produce roosters suitable for food use. This leads to about half of the chicks being “culled” (a less ugly euphemism than gassed or shredded) and used in–among other things–animal feed. Worldwide, billions of chicks are culled each year and that’s not counting other similar situations like male turkeys and female ducks.
A few years ago, Philip Peter started a little pet project. He wanted to build his own processor. This really isn’t out of the ordinary – every few months you’ll find someone with a new project to build a CPU out of relays, logic chips, or bare transistors. Philip is a software developer, though, and while the techniques and theory of building hardware haven’t changed much in decades, software development has made leaps and bounds in just the past few years. He’s on a quest to build a CPU out of discrete components.
Search the Internet for some tips and tricks for schematic capture programs like KiCad and Eagle, and you’ll find some terrible design choices. If you want more than one copy of a very specific circuit on your board, you have to copy and paste. Circuit simulation is completely separate from schematic capture and PCB design, and unit testing – making sure the circuit you designed does what it’s supposed to do – is a completely foreign concept. Schematic capture and EDA suites are decades behind the curve compared to even the most minimal software IDE. That’s where Philip comes in. By his own admission, he reinvented VHDL badly, but he does have a few ideas that are worth listening to.
This is the second in a two-part series looking at safety when experimenting with mains-voltage electronic equipment, including the voltages you might find derived from a mains supply but not extending to multi-kilovolt EHT except in passing. In the first part we looked at the safety aspects of your bench, protecting yourself from the mains supply, ensuring your tools and instruments are adequate for the voltages in hand, and finally with your mental approach to a piece of high-voltage equipment.
The mental part is the hard part, because that involves knowing a lot about the inner life of the mains-voltage design. So in this second article on mains voltages, we’ll look into where the higher voltages live inside consumer electronics.