Everyone is familiar with pinwheels, and few of us haven’t crafted one from a square of paper, a stick, and a pin. Pinwheels are pretty optimized from a design standpoint, and are so cheap and easy to build that putting a pinwheel to work as an HVAC duct flow meter seems like a great idea.
Great in theory, perhaps, but as [ItMightBeWorse] found out, a homemade pinwheel is far from an ideal anemometer. His experiments in air duct flow measurements, which previously delved into ultrasonic flow measurement, led him to try mechanical means. That calls for some kind of turbine producing a signal proportional to air flow, but a first attempt at using a computer fan with brushless DC motor failed when a gentle airflow couldn’t overcome the drag introduced by the rotor magnets. But a simple pinwheel, custom cut from patterns scaled down from a toy, proved to be just the thing. A reflective optosensor counts revolutions as the turbine spins in an HVAC duct, and with a little calibration the rig produces good results. The limitations are obvious: duct turbulence, flimsy construction, and poor bearings. But for a quick and dirty measurement, it’s not bad.
This is a solution to global warming. This solution will also produce electricity, produce rain in desertified areas, and transform the Sahara into arable land capable of capturing CO2. How is this possible? It’s simple: all we need to do is build a five-kilometer tall, twenty-meter wide chimney. Hot air, warmed by the Earth’s surface, will enter the base of the chimney and flow through turbines, generating electricity. From there, air will rise through the chimney, gradually cooling and transferring energy from the atmosphere at Earth’s surface to five kilometers altitude. This is the idea behind the Super Chimney, It’s an engineering concept comparable to building a dam across the Strait of Gibraltar, a system of gigantic mirrors in Earth’s orbit, or anything built under an Atoms for Peace project. In short, this is fringe engineering.
This is also, ‘saving the world with wacky waving inflatable arm flailing tube men.’
The idea of building tens of thousands of fabric chimneys, placing them all around the globe, and cooling the Earth while sequestering carbon dioxide is fantastic. Ideas are simple, implementation is something else entirely. There are also obvious problems with the physics presented in the Super Chimney presentation, but these problems don’t actually make a Super Chimney impossible. We need more eyes on this, so we’re opening this one up as an Ask Hackaday. What do you think of this audacious scheme, and is it even possible?
The piston engine has been the king of the transportation industry for well over a century now. It has been manufactured so much that it has become a sort of general-purpose machine that can be used to do quite a bit more than merely move people and cargo from one point to another. Running generators, hydraulic systems, pumps, and heavy machinery are but a few examples of that.
Scale production of this technology also had the effect of driving prices for these engines down, and now virtually everyone in the developed world has cheap and easy access to them. In the transportation world, at least, it looks like its reign might finally be coming to a slow, drawn-out conclusion as electric cars capture more and more market share.
Electric motors aren’t the first technology to try to topple the piston engine from its apex position on top of our modern transportation industry, though. In the 1960s another technology, the gas turbine engine, tried to replace it — and failed.
A while ago, [Marco] mounted a powerful laser diode to a CNC machine in an attempt to etch copper clad board and create a few PCBs. The results weren’t that great, but the technique was promising. In a new experiment, [Marco] purchased a very cheap laser engraver kit from China, and now this technique looks like it might be a winner.
[Marco] sourced his laser engraver from Banggood, and it’s pretty much exactly what you would expect for a CNC machine that costs under $200. The frame is aluminum extrusion, the motors are off-the-shelf steppers, the electronics are just Pololu-like drivers, and the software is somewhere between abysmal and terrible. Nevertheless, this machine can cut wood, leather, fabric, and can remove spray paint with a big blue laser diode.
To create his PCBs, [Marco] is first cleaning a piece of copper clad board, coating it with spray paint, then blasting it with a laser. The preferred software for this is LaserWeb, and the results are pretty good for a cheap machine.
There are a few extra steps to creating the PCB once the board has been coated with paint and blasted with a laser. This process still requires etching in either ferric chloride or some other mess of acid, but the results are good. So good, in fact, that [Marco] is experimenting with copper foil and Kapton to create flexible circuit boards. You can check out the video of these experiments below.
Did you know you can build fundamental circuits using biological methods? These aren’t your average circuits, but they work just like common electrical components. We talk alot about normal silicon and copper circuits ‘roud here, but it’s time to get our hands wet and see what we can do with the power of life!
In 1703, Gottfried Wilhelm Leibniz published his Explication de l’Arithmétique Binaire (translated). Inspired by the I Ching, an ancient Chinese classic, Leibniz established that the principles of arithmetic and logic could be combined and represented by just 1s and 0s. Two hundred years later in 1907, Lee De Forest’s “Audion” is used as an AND gate. Forty years later in 1947, Brattain and H. R. Moore demonstrate their “PNP point-contact germanium transistor” in Bell Labs (often given as the birth date of the transistor). Six years later in 1953, the world’s first transistor computer was created by the University of Manchester. Today, 13,086,801,423,016,741,282,5001 transistors have built a world of progressing connectivity, automation and analysis.
While we will never know how Fu Hsi, Leibniz, Forest or Moore felt as they lay the foundation of the digital world we know today, we’re not completely out of luck: we’re in the midst’s of our own growing revolution, but this one’s centered around biotechnology. In 1961, Jacob and Monod discovered the lac system: a biological analog to the PNP transistor presented in Bell Labs fourteen years earlier. In 2000, Gardner, Cantor, and Collins created a genetic toggle switch controlled by heat and a synthetic fluid bio-analog2. Today, AND, OR, NOR, NAND, and XOR gates (among others) have been successfully demonstrated in academic labs around the world.
But wait a moment. Revolution you say? Electrical transistors went from invention to computers in 6 years, and biological transistors went from invention to toggle button in 40? I’m going to get to the challenges facing biological circuits in time, but suffice it to say that working with living things that want to be fed and (seem to) like to die comes with its own set of challenges that aren’t relevant when working with inanimate and uncaring transistors. But, in the spirit of hacking, let’s dive right in. Continue reading “Living Logic: Biological Circuits For The Electrically Minded”→
For the last year or so, Monoprice has been teasing their follow-up to the fantastic $200 MP Select Mini. This is the $150 mini delta printer. We got a look at it last January at CES, it was on display at the Bay Area Maker Faire last May. Now there’s one on the Hackaday review desk.
Over the last few years, 3D printing has settled down into what most of us expected way back in 2010. No, not everyone wants, or arguably needs, a 3D printer on their desks. This is a far cry from the hype of a few years ago, leaving us with what we have today. 3D printers are just tools, much like a drill press or a laser cutter.
With that said, there still are some fantastic advances in 3D printing coming down from on high. Prusa will be shipping the 4-color multi-extruder add-on for the i3 Mk 2 shortly, and somehow or another we have infinite build volume printers. Still, there’s space to democratize 3D printing, and an opportunity for someone to release a very cheap, very good printer.
Monoprice was kind enough to send me a review unit of the MP Mini Delta before it officially hit their website. This is one of the first off the production line, alongside the few hundred pre ordered on an Indiegogo campaign earlier this year. Does this printer live up to expectations? It sure does, and that’s not just because it’s a $150 printer.
This would be an excellent printer at three times the price, and evidence enough that 3D printing is changing from a weird hobbyist thing to a proper tool.
If you sign up for a European hacker camp such as CCC Camp in Germany or SHA Camp in the Netherlands, you’ll see among the items recommended to take with you, a DECT handset. DECT, or Digital Enhanced Cordless Telecommunications, refers to the set of standards that lie behind the digital cordless telephones that are ubiquitous across Europe and some countries elsewhere in the world. These standards cover more than just the simple two-way telephone calls through a base station that most Europeans use them for though, they define a fully functional multi-cell 3G phone and data networking system. This means that an event like SHA Camp can run its own digital phone network without having to implement cell towers.
Olivetti promotional Net3 image
Reading the history of DECT, there is the interesting snippet that the first DECT product on the market in 1993 was not a telephone but a networking device, and incidentally the first wireless LAN product on the European market. Olivetti’s Net3 provided 512kB/s wireless networking to a base station with Ethernet or Token Ring interfaces for connection to a LAN. In its original form it was an internal card for a desktop PC coupled to a bulky external box containing radio circuitry and antenna, but its later incarnations included a PCMCIA card with a much smaller antenna box. The half-megabit speed seems tiny by today’s standards, but in the pre-multimedia world of 1993 would have been perfectly adequate for a Novell Netware fileserver and an HP Laserjet 4.
[Heinz Wolff] swallows a condom in another Olivetti promotional image.
Mystery Technology
So DECT is an interesting technology that can do more than just a simple cordless phone, and its first product was unexpectedly somewhat groundbreaking. It then becomes even more interesting to find that Net3 has left very little evidence of itself to find that can be found on the Web, and learning more about it requires a little detective work.
The Wikipedia entry has the bare bones, but it speaks volumes about the obscure nature of the product that the encyclopedia’s only picture of it is a tiny thumbnail-sized promotional image of the PCMCIA variant in a chunky mid-1990s laptop. A further search reveals a 1993 British Olivetti staff newsletter (PDF) carrying another promotional image of the desktop Net3 device featuring the then-well-known TV personality and academic [Heinz Wolff] demonstrating the technology bizarrely by swallowing a DECT medical instrumentation transponder wrapped in a condom. Some press releases remain in the fossilized remnants of the 1990s internet, and a Net3 design team member’s LinkedIn page led us to the patent covering the system, but that’s pretty much it. We can’t even find a high enough resolution image of a Net3 card for our featured image slot.
Wireless Things Before Their Time
It’s obvious that Net3 and DECT networking as a high-end wireless LAN before a need for wireless LANs existed never made it, but what is perhaps more interesting is that it seems to have left no legacy for other more mundane applications. We are in the midst of an explosion of hype around the Internet of Things and it seems new short-range wireless networking technologies appear almost daily, yet the world seems to have overlooked this robust, low power, and mature wireless network with its own dedicated frequency allocation that many of us already have in our homes. It seems particularly surprising that among the many DECT base stations on sale at your local consumer electronics store there are none with an Internet connection, and there is no market for IoT devices that use DECT as their backhaul.
In the open-source community there has been some work on DECT. The OsmocomDECT project for example provides a DECT software stack, and deDECTed.org states an aim to “better understand DECT and its security and to create an Open Source implementation of the DECT standard”. But there seems to have been very little hardware work in our community on the standard, for example there are no DECT-specific projects on Hackaday.io.
Net3 then was a product before its time, a herald of what was to come, from that twilight period when the Web was definitely a thing but had yet to become the world’s universal information repository. Public wireless networking was still several years in the future, so there was no imperative for road warriors to equip themselves with a Net3 card or for computer manufacturers — not even Olivetti themselves! — to incorporate the technology. It thus didn’t take the world by storm, and unusually for such a ground-breaking computer product there remains little legacy for it beyond a rarely-used feature of the protocol Europeans use for their cordless phones.
Did you have a Net3 card? Do you still have one? Let us know in the comments.
