We’ve known people to put down a small ice rink in their back yard during the winter. But a machine to resurface these diy rinks is unheard of until now. The big name in rink resurfacing is Zamboni, the person who invented this method of keeping the ice pristine.
This has almost everything you would find on a commercial model. The tires are studded with stainless steel screws for traction. The riding lawnmower has had its grass cutting blades replaced with a single steel blade that skims the surface of the ice. There’s even a tank of water which is distributed by a copper pipe with many holes and a squeegee which drags behind the machine. The only thing this is missing is a collection system for the slush which is generated by that skimmer blade. But as you can see in the clip after the break, it does just fine without it.
It’s our understanding that the video game industry has long been a driving force in new and better graphics processing hardware. But they’re not the only benefactors to these advances. As we’ve heard before, a graphics processing unit is uniquely qualified to process encryption hashes quickly (we’ve seen this with bitcoin mining). This project strings together 25 GPU cards in 5 servers to form a super fast brute force attack. It’s so fast that the actual specs are beyond our comprehension. How can one understand 348 billion hashes per second?
The testing was used on a collection of password hashes using LM and NTLM protocols. The NTLM is a bit stronger and fared better than the LM, but that’s not actually saying much. An eight character NTLM password will fall in 5.5 hours, while a 14 character LM hash makes it only about six minutes before the solution is discovered. Of course this type of hardware is only good if you have a copy of the password hashes themselves. Login protocols will lock out after a certain number of attempts and have measures in place to slow down automated systems like this one.
This video game gives your thumbs a rest while stretching those vocal chords. The pair of microphones seen above control the video game on the LCD display. Saying “Biu” will launch a projectile while “ahh” adjusts the flight path. The system was developed by [Tian Gao] as a final project for his ECE 4760 course at Cornell University.
The inputs are common computer microphones connected to some processing circuitry which he built on a piece of protoboard. This consists of some RC filtering and an LM358 opamp to get the signal ready for use with the ATmega1284. There is only one ADC on that chip so [Tian] alternates sampling from the microphones by using the multiplexer built into the chip. The video signal itself is an NTSC composite signal. To facilitate a reasonable frame rate he uses graphics that are packed in multiples of 8-bits. All in all this allows him to create a 160×200 pixel display.
All of this makes the game sound a little dry, but we dare you to listen to the video clip after the break without cracking a smile.
These water droplets are not falling; they’re actually stuck in place. What we’re seeing is the effects of an acoustic levitator. The device was initially developed by NASA to simulate microgravity. Now it’s being used by the pharmaceutical industry do develop better drugs.
The two parts of the apparatus seen in the image above are both speakers. They put out a sound at about 22 kHz, which is beyond the human range of hearing. When precisely aligned they interfere with each other and create a standing wave. The droplets are trapped in the nodes of that wave.
So are these guys just playing around with the fancy lab equipment? Nope. The levitation is being used to evaporate water from a drug without the substance touching the sides of a container. This prevents the formation of crystals in the solution. But we like it for the novelty and would love to see someone put one of these together in their home workshop.
Don’t miss the mystical demo in the clip after the break.
The folks over at Adafruit have been busy designing an LED matrix wristwatch for a while now. The circuit works great, but since this watch is powered by a coin cell battery, they’d really like to get the power consumption as low as possible. This means they needed a test rig to measure the consumption of each firmware revision, but how exactly do you build a voltage logger that works with voltages and currents this small? It turned out to be a very interesting project, with plenty of info on how to build an accurate voltage logger for really small projects.
As you can see, a series of white LEDs inside of the transparent case which provide the simulated sunrise. As the days get short and the nights longer we do see the benefit of having your clock brighten the room before it jolts you out of your slumber. Speaking of, that alarm sound seems to be the weak link in his design. He’s using a square wave smoothed with capacitors to drive a speaker at either end of the case. We didn’t hear an example but we imagine this not the most gentle of sounds.
The rest of the design is quite well done. He’s using a 4×20 Character LCD display and adjusts the backlight using PWM. A DCF77 radio feeds data from an atomic clock signal to the MSP430 chip which runs the clock. There’s even a battery backup in case the power goes out.
The PlayStation Development Network is hosting a six-month long competition to develop homebrew games for the original PlayStation.We don’t get many homebrew games for old systems in our tip line, so if you’d like to show something off, send it in.
This is how you promote a kickstarter
[Andy] has been working on an SNES Ethernet adapter and he’s finally got it working. Basically, it’s an ATMega644 with a Wiznet adapter connected to the second controller port. The ATMega sends… something, probably not packets… to the SNES where it is decoded with the help of some 65816 assembly on a PowerPak development cartridge. Why is he doing this? To keep track of a kickstarter project, of course.
What exactly is [Jeri] building?
[Jeri] put up an awesome tutorial going over the ins and outs of static and dynamic flip-flops. There’s a touch of historical commentary explaining why dynamic registers were used so much in the 70s and 80s before the industry switched over to static designs (transistors were big back then, and dynamic systems needed less chip area). At the end of her video, [Jeri] shows off a bucket-brigade sequencer of sort that goes through 15 unique patterns. We’re just left wondering what it’s for.
Nintendo gave [MikenGary] a Wii U and asked them to make a film inspired by 30 years of Nintendo lore and characters. They did an awesome job thanks in no small part to Hackaday boss man [Caleb](supplied the fire), writer [Ryan] (costume construction) and a bunch of people over at the Squidfoo hackerspace.
