We don’t need to mention that flip-dot displays are awesome. They use no power except in transitions, are visible on even the brightest of days, and have a bit of that old-school charm. So then it stands to reason that the flip-dot display that [AncientJames] made out of LEGO is awesome-plus. Heck, it even spells out “awesome”.
With over 40,000 pieces in his possession, [Mike] is definitely a huge fan of LEGO. Given that he’s also very much a fan of technology, it’s no surprise that he has built more than one type of LEGO computer case. He wrote in to tell us that he’s finished work on a well-rounded system designed for everyone.
[Mike] is no stranger to interesting case builds. In the last couple of years, he’s also made a functioning wind tunnel case and a bio computer that uses generated heat to warm soil for wheat grass plants. In the course of planning the LEGO computer, he thought a lot about heat and airflow, ultimately deciding on a top-down cooling path.
He’s quoting custom LEGO computer builds, providing the choice between an i3, i5, or i7 with either 8 or 16 gigs of RAM. They will run Linux or Windows 7/8 and are 10-compatible. There are a few choices for the top of the case: classic LEGO brick, the industrial look with diagonal slats, and a colored, tiled top. These systems are completely upgradeable and are held firmly together with great engineering and the occasional support rod.
If you’ve ever used an old-school analog oscilloscope (an experience everyone should have!) you probably noticed that the trace is simply drawn by a beam that scans across the CRT at a constant rate, creating a straight line when there’s no signal. The input signal simply affects the y-component of the beam, deflecting it into the shape of your waveform. [Steve] wrote in to let us know about his home-built “oscilloscope” that works a lot like a simple analog oscilloscope, albeit with a laser instead of a CRT.
[Steve]’s scope is built out of a hodgepodge of parts including Lego, an Erector set, LittleBits, and a Kano Computer (based on a Raspberry Pi). The Pi generates a PWM signal that controls the speed of a LittleBits motor. The motor is hooked up to a spinning mirror that sweeps the laser across some graph paper, creating a straight laser line.
After he got his sweep working, [Steve] took a small speaker and mounted a mirror to its cone. Next he mounted the speaker so the laser’s beam hits the mirror on the speaker, the spinning sweep mirror, and finally the graph paper display. The scope’s input signal (in this case, audio from a phone) is fed into the speaker which deflects the laser beam up and down as it is swept across the paper, forming a nice oscilloscope-like trace.
While [Steve]’s scope might not be incredibly usable in most cases, it’s still a great proof of concept and a good way to learn how old oscilloscopes work. Check out the video after the break to see the laser scope in action.
For nearly 130 years, the kilogram has been defined by a small platinum and iridium cylinder sitting in a vault outside Paris. Every other unit of measurement is defined by reproducible physical phenomenon; the second is a precise number of oscillations of a cesium atom, and a meter is the length light travels in 1/299792458th of a second. Only the kilogram is defined by an actual object, until NIST and the International Committee of Weights and Measures defines it as a function of the Planck constant. How do you measure the Planck constant? With a Watt balance. How do you build a Watt balance? With Lego, of course.
A Watt balance looks like a double-armed scale where one weight can be compared to another weight of known mass. Instead of using two arms, a Watt balance only has one arm, brought into balance by a current flowing through a coil. The mechanical power in the balance – brought about by whatever is on the balance plate – can then be compared to the electrical power, and eventually the Planck constant. This will soon be part of the formal definition of the kilogram, and yes, a machine to measure this can be made out of Lego.
The only major non-Lego parts in the Lego Watt balance are a few coils of wire wound around a PVC pipe and a few neodymium magnets. These are placed on both arms of the balance, and a pair of lasers are used to make sure both arms of the balance are level. Data are collected by measuring the coils through a few analog pins on a Labjack and a Phidget. Once the voltage and current induced in each coil is measured, the Wattage can be calculated, then the Planck constant, and finally how close the mass on the balance pan is to a real, idealized kilogram. Despite being made out of Lego, this system can measure a gram mass to 1% uncertainty.
The authors have included a list of Lego parts, most of which could be found in any giant tub of Lego in an 8-year-old’s closet. The only really expensive item on the BOM is a 16-bit USB DAQ; apart from that, it’s something anyone can build.
Thanks [Matt] for the tip.
Developing film at home is most certainly a nearly forgotten art nowadays, but there are still a few very dedicated people who care enough to put in the time and study to this craft. [Jan] is one of the exceptional ones. He’s developing 35mm film with Lego (Dutch, Google translate).
For the build, [Jan] is using the Lego RCX 1.0, the first gen of the Lego Mindstorms, released in the late 90s. According to eBay, this is a significantly cheaper option for programmable Lego. The mechanics of the Lego film developer consisted of multiple tanks of chemicals. The film was loaded on a reel, suspended from a Lego gantry, and dunked into each tank for a specific amount of time.
A second revision of the hardware (translate) was designed, with the film loaded into a rotating cylinder. A series of chemicals would then be pumped into this unit with the hope of reducing the amount of chemicals required. This system was eventually built using the wiper fluid pump from a car. Apparently, the system worked well, judging from the pictures developed with this system. Whether it was easy or efficient is another matter entirely.
You can check out a video of the first revision of the Lego film developing system below.
Thanks [Andrew] for sending this in.
Have some .40 cal shell casings sitting around with nothing to do? How about some bullet earbuds? If you’ve ever wondered about the DIY community over at imgur, the top comment, by a large margin, is, “All of these tools would cost so much more than just buying the headphones”
Here’s something [Lewin] sent in. It’s a USB cable, with a type A connector on one end, and a type A connector on the other end. There is no circuitry anywhere in this cable. This is prohibited by the USB Implementors Forum, so if you have any idea what this thing is for, drop a note in the comments.
Attention interesting people in Boston. There’s a lecture series this Tuesday on Artificial Consciousness and Revolutionizing Medical Device Design. This is part two in a series that Hackaday writer [Gregory L. Charvat] has been working with. Talks include mixed signal ASIC design, and artificial consciousness as a state of matter. Free event, open bar, and you get to meet (other) interesting people.
Let’s say you need to store the number of days in each month in a program somewhere. You could look it up in the Time Zone Database, but that’s far too easy. How about a lookup table, or just a freakin’ array with 12 entries? What is this, amateur hour? No, the proper way of remembering the number of days in each month is some bizarre piece-wise function. It is: f(x) = 28 + (x + ⌊x⁄8⌋) mod 2 + 2 mod x + 2 ⌊1⁄x⌋. At least the comments are interesting.
Arduinos were sold in the 70s! Shocking, yes, but don’t worry, time travel was involved. Here’s a still from Predestination, in theatres Jan 9, rated R, hail corporate.
Remember in the late 90s and early 2000s when everything had blue LEDs in them? Blinding blue LEDs that lit up a dark room like a Christmas tree? Nobel prize. There’s a good /r/askscience thread on why this is so important. The TL;DR is that it’s tough to put a p-type layer on gallium nitride.
Have a Segway and you’re a member of the 501st? Here’s your Halloween costume. It’s a model of the Aratech 74-Z speeder bike, most famously seen careening into the side of trees on the forest moon of Endor.
[Andrew] needed something to do and machined an iPhone 5 out of a block of aluminum. Here’s the video of icon labels being engraved. The machine is a Denford Triac with a six station auto tool changer. He’s running Mach3, and according to him everything – including the correct tooling – cost far too much money.
Another [Andrew] was working the LEGO booth at Maker Faire New York and has finally gotten his LEGO Mindstorms Minecraft Creeper build written up. Yes, it’s probably smarter than your average Minecraft Creeper, and this one also blows up. He also had a physical version of the classic video game from 1979, Lunar Lander. Both are extremely awesome builds, and a great way to attract kids of all ages to a booth.
[Wilfred] was testing a titanium 3D printer at work and was looking for something to print. The skull ‘n wrenches was a suitable candidate, and the results are fantastic. From [Wilfred]: “Just out of the printer the logo looks amazing because it isn’t oxidized yet (inside the printer is an Argon atmosphere) Then the logo moves to an oven to anneal the stress made by the laser. But then it gets brown and ugly. After sandblasting we get a lovely bluish color as you can see in the last picture.”
The folks at Lulzbot/Aleph Objects are experimenting with their yet-to-be-released printer, codenamed ‘Begonia’. They’re 2D printing, strangely enough, and for only using a standard Bic pen, the results look great.
Everyone is going crazy over the ESP8266 UART to WiFi module. There’s another module that came up on Seeed recently, the EMW3162. It’s an ARM Cortex M3 with plenty of Flash, has 802.11 b/g/n, and it’s $8.50 USD. Out of stock, of course.