The Air Multiplier Fan Principle, Applied To A Jet Engine

January 28, 2022 by 26 Comments

Many readers will be familiar with the Dyson Air Multiplier, an ingenious bladeless fan design in which a compressor pushes jets of air from the inside edge of a large ring. This fast-moving air draws the surrounding air through the ring, giving the effect of a large conventional fan without any visible moving parts and in a small package. It’s left to [Integza] to take this idea and see it as the compressor for a jet engine, and though the prototype you see in the video below is fragile and prone to melting, it shows some promise.

His design copies the layout of a Dyson with the compressor underneath the ring, with a gas injector and igniter immediately above it. The burning gas-air mixture passes through the jets and draws the extra air through the ring, eventually forming a roaring jet engine flame exhaust behind it. Unfortunately the choice of 3D print for the prototype leads to very short run times before melting, but it’s possible to see it working during that brief window. Future work will involve a non-combustible construction, but his early efforts were unsatisfactory.

It’s clear that he hasn’t created the equivalent of a conventional turbojet. Since it appears that its operation happens when the flame has passed into the center of the ring, it has more in common with a ramjet that gains its required air velocity with the help of extra energy from an external compressor. Whether he’s created an interesting toy or a useful idea remains to be answered, but it’s certainly an entertaining video to watch.

Meanwhile, this isn’t the first project we’ve seen inspired by the Air Multiplier.

Continue reading “The Air Multiplier Fan Principle, Applied To A Jet Engine” →

Game Boy Becomes Super Game Boy With A Pair Of Pis

January 14, 2022 by 13 Comments

For the Nintendo aficionados of the 90s, the Super Game Boy was a must-have cartridge for the Super Nintendo which allowed gamers to play Game Boy games on your TV. Not only did it allow four-color dot-matrix gaming on the big screen, but it let you play those favorite Game Boy titles without spending a fortune on AA batteries. While later handhelds like the PSP or even Nintendo Switch are able to output video directly to TVs without issue, the original Game Boy needed processing help from an SNES or, as [Andy West] shows us, it can also get that help from a modern microcontroller.

Testing the design before installing it in the NES case.

The extra processing power in this case comes from a Raspberry Pi Pico which is small enough to easily fit inside of a donor NES case and also powerful enough to handle the VGA directly. For video data input, the Pico is connected to the video pins on the Game Boy’s main board through a level shifter. The main board is also connected to a second Pico which handles the controller input from an NES controller. Some fancy conversion needed to be done at this point because although the controller layouts are very similar, they are handles by the respective consoles completely differently.

With all of the technical work largely out of the way, [Andy] was able to put the finishing touches on the build. These included making sure the power buttons, status LEDs, and reset button all functioned, and restoring the NES case complete with some custom “Game Guy” graphics to match the original design of the Game Boy. We commend the use of original Game Boy hardware in this build as well, which even made it possible for [Andy] and his wife to play a head-to-head game of Dr. Mario through a link cable with another Game Boy. If you’re looking for a simpler way of playing on original hardware without burning a hole in your wallet buying AA batteries, take a look at this Game Boy restoration which uses a Lithium battery instead.

Continue reading “Game Boy Becomes Super Game Boy With A Pair Of Pis” →

Rohde & Schwarz FSIQ 7 Logic Analyzer's RF module, back side. (Source: Roberto Barrios)

Rohde & Schwarz FSIQ Signal Analyzer IF-Filter Module Repair

January 12, 2022 by 9 Comments

Who can’t resist snapping up a piece of really expensive laboratory testing gear for next to nothing when browsing eBay or similar? Maybe it’s giving you mournful eyes when browsing through a yard sale. Often such gear is sold for cheap because it’s defective, but with a bit of attention, can be brought back to life. This is how [Roberto Barrios] ended up with a Rohde & Schwarz FSIQ 7 signal analyzer lounging around his place for a few months until he got it fixed.

See anything wrong with this picture?

Part of the fix was replacing a busted RF converter module (A160 IF-Filter) with a used-but-working replacement, but this left the device with odd calibration failures. In the process of tracing down the cause, [Roberto] took many high-resolution images of both sides of the PCBs in order to reverse-engineer the circuit. To complicate matters, the calibration results indicated that the unit’s filters were fine on boot-up, but would deviate after a few minutes.

After extending the filter module to work outside the enclosure and experimental use of a hot air gun, ultimately the cause was tracked down to an unsoldered pad. Considering the extremely simple cause of the failure, it would seem that R&S QA had an off-day when that replacement module was produced. If there’s a lesson to be learned here it is probably that a simple visual inspection is sometimes all that is needed to fix a hardware issue.

What are your expensive gear repair stories? What did you learn that could save others hours of their time?

A man welds on a chassis

Electric Wheelchair Dump Truck Hack Really Hauls

December 30, 2021 by 5 Comments

Have you ever looked at a derelict electric wheelchair and thought “I bet I could make something great with that!” Of course you have- this is Hackaday, after all! And so did [Made in Poland], who managed to get a hold of a broken down electric wheelchair and put the full utility of his well equipped metalworking shop to work. The results? Lets just say it hauls.

What we really enjoyed about the build was that there wasn’t much that couldn’t be done by an average garage hacker with a drill press, angle grinder, and a stick welder. While it’s definitely nicer to have a lathe and a high quality welding table, plasma cutter, and everything in between, nothing that [Made in Poland] did in the video is such high precision that it would require those extensive tools. There may be some parts that would be a lot more difficult, or lower precision, but still functional.

Another aspect of the build is of course the control circuitry and user interface. Keeping the skid steer and castor approach meant that each motor would need to be controllable independently. To achieve this, [Made in Poland] put together a purely electromechanical drive controlled with momentary rocker switches and automotive relays to form a simple H-Bridge for each motor.

Of course you just have to watch until the end, because it really proves that a man will do anything to get out of hauling wood around! Old electric wheelchairs can also make a great base for big robots, as it turns out.

Continue reading “Electric Wheelchair Dump Truck Hack Really Hauls” →

The Real Science (Not Armchair Science) Of Consciousness

December 15, 2021 by 43 Comments

Among brain researchers there’s a truism that says the reason people underestimate how much unconscious processing goes on in your brain is because you’re not conscious of it. And while there is a lot of unconscious processing, the truism also points out a duality: your brain does both processing that leads to consciousness and processing that does not. As you’ll see below, this duality has opened up a scientific approach to studying consciousness.

Are Subjective Results Scientific?

Researcher checking fMRI images.
Checking fMRI images.

In science we’re used to empirical test results, measurements made in a way that are verifiable, a reading from a calibrated meter where that reading can be made again and again by different people. But what if all you have to go on is what a person says they are experiencing, a subjective observation? That doesn’t sound very scientific.

That lack of non-subjective evidence is a big part of what stalled scientific research into consciousness for many years. But consciousness is unique. While we have measuring tools for observing brain activity, how do you know whether that activity is contributing to a conscious experience or is unconscious? The only way is to ask the person whose brain you’re measuring. Are they conscious of an image being presented to them? If not, then it’s being processed unconsciously. You have to ask them, and their response is, naturally, subjective.

Skepticism about subjective results along with a lack of tools, held back scientific research into consciousness for many years. It was taboo to even use the C-word until the 1980s when researchers decided that subjective results were okay. Since then, here’s been a great deal of scientific research into consciousness and this then is a sampling of that research. And as you’ll see, it’s even saved a life or two.

Continue reading “The Real Science (Not Armchair Science) Of Consciousness” →

Oh Deere, Is That Right To Repair Resolution Troubling You?

December 14, 2021 by 103 Comments

Over the years a constant in stories covering the right to repair has come from an unexpected direction, the farming community. Their John Deer tractors, a stalwart of North American agriculture, have become difficult to repair due to their parts using DRM restricting their use to authorised Deere agents. We’ve covered farmers using dubious software tools to do the job themselves, we’ve seen more than one legal challenge, and it’s reported that the price of a used Deere has suffered as farmers abandon their allegiance to newer green and yellow machines. Now comes news of a new front in the battle, as a socially responsible investment company has the tractor giant scrambling to block their shareholder motion on the matter.

Deere have not been slow in their fight-back against the threat of right-to-repair legislation and their becoming its unwilling poster-child, with CTO Jahmy Hindman going on record stating that 98% of repairs to Deere machinery can be done by the farmer themself (PDF, page 5) without need for a Deere agent. The question posed by supporters of the shareholder action is that given the substantial risk to investors of attracting a right-to-repair backlash, why would they run such a risk for the only 2% of repairs that remain? We’d be interested to know how Deere arrived at that figure, because given the relatively trivial nature of some of the examples we’ve seen it sounds far-fetched.

It’s beyond a doubt that Deere makes high-quality agricultural machinery that many farmers, including at least one Hackaday scribe, have used to raise a whole heap of crops. The kind of generational brand loyalty they have among their customers simply can’t be bought by clever marketing, it’s been built up over a century and a half. As spectators to its willful unpicking through this misguided use of their repair operation we hope that something like this shareholder move has the desired effect of bringing it to a close. After all, it won’t simply be of benefit to those who wish to repair their tractor, it might just rescue their now-damaged brand before it’s too late.

Curious about previous coverage on this ongoing story? This article from last year will give context.

Header image: Nheyob / CC BY-SA 4.0

Anr air quality sensor mounted on a bike's handlebar

Measuring Air Quality Using Mobile Sensors For The Masses

December 13, 2021 by 8 Comments

Poor air quality is a major problem for city dwellers the world over. Dust, smoke, particles and noxious gases from vehicles, industry and agriculture makes many megacities downright hazardous to live in. Pinpointing the source of pollution and developing strategies for mitigation requires accurate data on pollutant levels, but obtaining these numbers is not always easy.

Enter CanAirIO, a citizen science project that aims to gather air quality data from around the world by putting sensors into the hands of as many people as possible. Its team has developed two different sensor nodes for this purpose: an indoor one that can measure CO2, and a mobile one that can measure particulate matter (PM) levels. Both versions are powered by an ESP32 microcontroller that reads out the air quality sensors and connects to the Internet using WiFi or BlueTooth. The data can then be shared online to create detailed maps showing local variations in air quality.

The design of the sensor nodes is fully open-source, allowing anyone with basic electronic skills to build them. The sensors are a Sensirion SCD30 for CO2 measurement and an SPS30 for PM levels. The mobile version comes with a neat 3D-printed enclosure that can be mounted on a bike’s handlebar, enabling the user to quickly gather data around their neighbourhood. A mobile app simplifies setting up the sensors and sharing the data.

The project has already been successful in gathering detailed data in the city of Bogotá, Colombia, and will no doubt prove useful in many other pollution hotspots around the world. We’ve seen similar community efforts to monitor air pollution and even radiation in various places, both showing how relatively simple devices can help to make a difference in people’s wellbeing. Continue reading “Measuring Air Quality Using Mobile Sensors For The Masses” →