[Brek] needed to store 64 bits of data from his GPS to serve as a last-known-position function. This memory must be non-volatile, sticking around when the GPS and power are off. Solutions like using a backup battery or employing a $0.25 EEPROM chip were obviously too pedestrian. [Brek] wanted to store his 64 bits in style and that means hand-wired core memory.
OK, we’re pretty sure that the solution came first, and then [Brek] found a fitting problem that could be solved, but you gotta give him props for a project well executed and well documented.
Continue reading “Core Memory for the Hard Core”
When you are a hardware guy and you live in a time of crisis, sooner or later you find yourself working for some casino equipment company. You become an insider and learn a lot about their tricks. I’ve been in touch with that business for about 30 years. I made a lot of projects for gambling machines which are currently in use, and I had a lot of contact with casino people, both owners and gamblers.
Now I’m sure you expect of me to tell you about the tricks they use to make you spend your money. And I will: there are no technical tricks. This isn’t because they are honest people, but because they don’t need it. Mathematics and Psychology do all the work.
Does the risk of gambling pay off? Mathematically speaking, no – but it’s up to you to decide for yourself. One thing is for certain – whether you decide to gamble or not, it’s good to know how those casino machines work. Know thy enemy.
Continue reading “Beating the Casino: There is No Free Lunch”
For years we have been graced by cheap consumer electronics that are able to be upgraded through unofficial means. Your Nintendo DS is able to run unsigned code, your old XBox was a capable server for its time, your Android smartphone can be made better with CyanogenMod, and your wireless router could be expanded far beyond what it was originally designed to do thanks to the efforts of open source firmware creators. Now, this may change. In a proposed rule from the US Federal Communications Commission, devices with radios may be required to prevent modifications to firmware.
The proposed rule only affects devices operating in the U-NII bands; the portion of the spectrum used for 5GHz WiFi, and the proposed rule only affects the radios inside these devices. Like all government regulations, the law of unintended consequences rears its ugly head, and the proposed rules effectively ban Open Source router firmware.
The rules require all relevant devices to implement software security to ensure the radios of devices operating in this band cannot be modified. Because of the economics of cheap routers, nearly every router is designed around a System on Chip – a CPU and radio in a single package. Banning the modification of one inevitably bans the modification of the other, and eliminates the possibility of installing proven Open Source firmware on any device.
Build a better mousetrap, and the world will beat a path to your door, but what about a smarter mousetrap? [Alain] decided to find out by making a Raspberry Pi-powered, Internet-connected smart trap. The brains of the operation is a Pi running Arch Linux. Connected to that is a IR trigger, a servo to unlatch the sliding door, and a camera to see your new friend.
The housing of the trap is CNC cut foam PVC board, which is both easy to cut and to clean. Once the IR beam is broken the Pi turns the servo, which pulls a pin on the front door. Once your new friend is settled in a LED light turns on to illuminate the subject, a picture is taken and sent via email.
With automated alerts you don’t have to manually check the trap, and you also don’t have to worry about a trapped animal being inside for too long. Join us after the break for a demonstration video showing off all the features, and a real world example.
Continue reading “Building a Better Mousetrap With The Raspberry Pi”
[K.C. Lee]’s entry for the Hackaday Prize won’t cure cancer, wipe a disease from the planet, stop an alien invasion, or save the world. His battery charger and analyzer is, however, a useful little device for determining the charge and discharge characteristics of batteries, and can also be used as dual channel electronic load, current source, or power supply.
Inside [K.C.]’s device are all the tools required for charging and discharging lithium-ion, lead acid, and NiMH batteries. He’s doing this with a few slightly unusual circuits, including a SEPIC DC to DC converter, and an ‘analog’ PWM controller. these two techniques together mean [K.C.] can get away with smaller caps and inductors in his design, which also means less ripple on the output. As far as battery chargers and dischargers go, this one is very well designed.
Control of battery discharging and charging happens through a SILabs 8051-based microcontroller with USB. The UI is a simple Nokia LCD and an app running in Windows. If you want to save the world, this isn’t the project for you. If you need to test a few rechargeable batteries, this is a great device to have on the workbench.
I still remember the first time I saw a satellite, I was 12 years old and was camping far away from the city lights. As I gazed up at the night sky, I could actually track satellites with my naked eye as they zoomed across the night’s sky. It was amazing. Nowadays, it’s getting harder to spot relatively small satellites with light pollution from large cities.
The International Space Station (ISS) on the other hand is a large piece of hardware — it’s about the size of a football field, and according to NASA it’s the second brightest object in the night sky. So why don’t we see it more often? Well, part of the reason is that you don’t know where to look. [Grady Hillhouse] set out to change that by building a what is basically a 2 degrees of freedom robot arm that will point you to where the ISS is at any given moment.
[Grady] uses a stepper motor for the azimuth, and a standard servo for the elevation, all powered by an Nucleo F401 development board, and an Adafruit motor shield and slip ring. The structure is made using some Erector set like parts from Actobotics.
He wrote the code from this open source project here. He’s currently cleaning up his code, and says he’ll be posting it up shortly. In the mean time, you can watch a video detailing the build in the video after the break. Or if you can’t wait, you can visit NASA’s web site to receive email or SMS messages on when the ISS is view-able in your hood.
Continue reading “It’s 10 PM, Do You Know Where Your Space Station Is At?”
A month ago, we ran a post about [Jim]’s rare and strange transparent microchips. He’s back at it again, this time taking a look at the inner workings of MOSFETs
The Unallocated Space hackerspace is moving, and they’re looking for a few donations to get the ball rolling.
Yes, it’s a Kickstarter for a 3D printer, but the LumiPocket is interesting, even if only on the basis of the engineering choices. It’s a UV laser resin printer, and they’re using a SCARA arm to move the laser around. They’re also doing a top-down resin tank; it requires more resin, but it seems to work well enough.
Around DC or northern Virginia? We’re going to be there on September 11th through the 13th. We’re holding a Hackaday Prize Worldwide meetup at Nova Labs in Reston, Virgina. Sign up now! Learn KiCAD with [Anool]! Meet [Sudo Bob]! It’ll be a blast.
Not around DC or NOVA? This Wednesday we’ll be hosting another chat on .io.
The GEnx is one of the most beautiful and advanced engines in the world, and that means [Harcoreta] oven on the RC groups forums has made one of the most beautiful electric ducted fans in the world. On the outside, it looks like a GEnx, including reverse thrust capabilities, but inside it’s pure electronics: a brushless motor rotates a 100mm, 18-blade fan. He’s hoping to mount it on a Bixler (!). We can’t wait for the video of the maiden.