Joker Monitor Keeps An Eye On Hazardous Gas Levels

July 23, 2021 by Lewin Day 12 Comments

The Joker is a popular character in the Batman franchise, and at times uses poisonous gases as part of his criminal repertoire. That inspired this fun project by [kutluhan_aktar], which aims to monitor the level of harmful gases in the air.

The project doesn’t use just one gas sensor, but several! It packs the MQ-2, MQ-3, MQ-4, MQ-6, and MQ-9. This gives it sensitivity to a huge variety of combustible gases, as well as detecting carbon monoxide. The sensors are read by an Arduino Nano, which displays results on an RGB LED as well as an attached IPS screen.

Readings from each sensor can be selected by using an infrared remote. In order to best work as a safety device, however, it could be more useful to have the Arduino automatically cycle through each sensor, checking them periodically and raising an alarm in the event of a high reading.

The whole project is built on a custom PCB which is artfully constructed with an image of the Joker himself. It helps to make the project a bit more of a display piece, and speaks to the aesthetic skills of its creator.

It’s a fun build, and one that could be mighty capable with a few software tweaks. With that said, if you’re working in a space with real hazards from combustible gases, it may be worth investing in some properly rated safety equipment rather than relying on an Arduino project.

Incidentally, if you’d like to improve the results from using such gas sensors, we’ve looked at that in the past. Video after the break.

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PnPAssist: A “Smart” Build Platform For Manual PCB Assembly

July 23, 2021 by Danie Conradie 16 Comments

Open source pick and place machines have come a long way in the past years, but are not necessarily worth the setup time and machine cost if you are only building a few PCBs at a time. [Nuri Erginer] found himself in this situation regularly, so he created PnPAssist, a “smart” build platform to speed up manual PCB assembly. Video after the break.

The PnP assist consists of a small circular platform that can automatically translate and rotate to place the current footprint in the middle of the platform, right in the center of your microscope’s view, and a laser crosshair. The entire device can also rotate freely on its base to avoid contorting your arm to match the footprint orientation. Just export the PnP file from your favorite PCB design software, load it on a micro SD card, plug it into the PnPAssist, and start assembling. The relevant component information is displayed on a small OLED display right on the machine. [Nuri] has also created a component organizing tray that will indicate the correct compartment with an RGB LED.

Below the build platform, a 3D printed gear is in contact with a pair of parallel lead screws driven by stepper motors. The relative motion of the lead screws allows the platform to rotate, translate, or both. This arrangement also means the machine is a lot more compact than a conventional XY-table and can be packed away when not in use. The base is held firmly in place on the workbench with a set of suction cups or screws. Power is provided through the fixed base using a slip-ring, so there are no cables to twist up as you spin the machine around. Continue reading “PnPAssist: A “Smart” Build Platform For Manual PCB Assembly” →

A Nerf Ball Turret Complete With FPV

July 23, 2021 by Lewin Day 2 Comments

Sentry turrets have long been a feature of science fiction films and video games. These days, there’s nothing stopping you from building your own. [otjones99] has done just that, with his FPV Nerf Ball launcher.

The system works on the basic principle of launching soft foam balls via a pair of counter-rotating wheels. It’s a remarkably simple way of electrically launching projectiles without a lot of fuss and mucking around, and it works well here. A blower fan is used to gently roll ammunition towards the launcher wheels as required. There’s a hopper-style clip which uses a servo to drop one ball at a time into the launching tube.

An Arduino Uno is responsible for slewing the turret, and handling the firing process. A joystick is fitted with an NRF24L01 radio module to send signals to the Arduino to aim the turret, while an FPV camera mounted on the turret allows the user to remotely see what the turret is aiming at. With a simple pull of the joystick’s trigger, the turret opens fire.

It’s a fun build, and one that shouldn’t do too much damage to anything given the soft pliable nature of the Nerf ammunition. Of course, if you don’t want to aim your turret yourself, you can always go ahead and build yourself an automated sentry gun. Video after the break.

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Arm Researchers Announce The PlasticArm

July 23, 2021 by Chris Lott 19 Comments

If the Cortex family of embedded microprocessors aren’t flexible enough for your designs, an article published this week (click here for the PDF version) in the journal Nature might be of interest. We’re not talking flexibility in terms of features, but real, physical flexibility of the microprocessor itself. A research team from Arm Ltd. has developed the PlasticArm, which is a 32-bit processor derived from the Cortex-M0+ family.

They accomplished this by constructing a CPU from metal-oxide thin-film transistors (TFT) on a polyimide substrate, the resultant chip being called a natively flexible microprocessor. While much of the hype focuses on the flexibility aspect, we think the real innovation here is the low cost. The processes used to deposit transistors onto silicon wafers is much more expensive than those on this flexible substrate.

Don’t get too excited just yet, because there were some compromises made along the way. Modern microprocessor silicon dies are measured in the tens of microns, but the PlasticArm total die size is a comparatively whopping 9 mm square. The researchers were appropriately focused on the core CPU, and the auxiliary building blocks such as ROM and RAM seem almost an afterthought. With only 456 bytes of program store and 128 bytes of RAM, only the tiniest of applications are suited to this chip. Other compromises were made, such as no internal registers — they are mapped to the external RAM — and the CPU runs a lot slower than we’re used to, topping out at 29 kHz (note: k not M).

There are certainly some challenges with this new technology, and we won’t be designing with these chips any time soon. But it has the potential to offer benefits in certain niche applications where low-cost and/or flexibility is more important than processor speed and performance.

New Privacy Policy Gets Audacity Back On Track

July 23, 2021 by Tom Nardi 29 Comments

Regular readers will likely be aware of the considerable debate over changes being made to the free and open source audio editor Audacity by the project’s new owners, Muse Group. The company says their goal is to modernize the 20 year old GPLv2 program and bring it to a larger audience, but many in the community have questioned whether the new managers really understand the free software ethos. An already precarious situation has only been made worse by a series of PR blunders Muse Group has made over the last several months.

But for a change, it seems things might be moving in the right direction. In a recent post to Audacity’s GitHub repository, Muse Group unveiled the revised version of their much maligned Privacy Policy. The announcement also came with an admission that many of the key elements from the draft version of the Privacy Policy were poorly worded and confusing. It seems much of the problem can be attributed to an over-analysis of the situation; with the company inserting provocative boilerplate protections (such as a clause saying users must be over the age of 13) that simply weren’t necessary.

Ultimately, the new Privacy Policy bears little resemblance to the earlier draft. Which objectively, is a good thing. But it’s still difficult to understand why Muse Group publicly posted such a poorly constructed version of the document in the first place. Project lead Martin Keary, better known online as Tantacrul, says the team had to consult with various legal teams before they could release the revised policy. That sounds reasonable enough, but why where these same teams not consulted before releasing such a spectacularly ill-conceived draft?

The new Privacy Policy makes it clear that Audacity won’t be collecting any user data, and what little personally identifiable information Muse Group gets from the application when it automatically checks for an update (namely, the client’s IP address) isn’t being stored. It’s further explained in the GitHub post that the automatic update feature only applies to official binary builds of Audacity, meaning it will be disabled for Linux users who install it through their distribution’s package repository. The clause about working with unnamed law enforcement agencies has been deleted, as has the particularly troubling age requirement.

Credit where credit is due. Muse Group promised to revise their plans for adding telemetry to Audacity, and judging by the new Privacy Policy, it seems they’ve done an admirable job of addressing all of the issues brought up by the community. Those worried their FOSS audio editor of choice would start spying on them can rest easy. Unfortunately the issue of Audacity’s inflammatory Contributor License Agreement (CLA) has yet to be resolved, meaning recently christened forks of the audio editor dedicated to preserving its GPLv2 lineage are unlikely to stand down anytime soon.

Are Hackers Being Let Down In Education?

July 23, 2021 by Jenny List 62 Comments

In my work for Hackaday over the years I have been privileged to interact with some of the most creative people I have ever met, I have travelled far more than I ever did when I toiled unseen in an office in Oxford, and I have been lucky enough to hang out in our community’s spaces, camps, and dives across Europe.

Among the huge diversity of skills and ideas though, it’s striking how many of us share similar experiences and histories that have caused us to find our people in rooms full of tools and 3D printers. One of these things I found surprising because I thought I was the only one; I never fit in with the other kids at school, I found much of the teaching incomprehensible and had to figure things out for myself. As an exercise recently I did a straw poll among some of my friends, and found that a significant majority had a similar experience. Clearly something must have gone badly wrong in the way we were being taught that so many of us could have been let down by our schooling, and maybe to understand the needs of our community it’s time to understand why.

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Hackaday Podcast 128: 3D-Printing Injection Molds, Squiggly Audio Tape, Curvy Mirrors, And Space Cadets

July 23, 2021 by Mike Szczys No comments

Hackaday editors Elliot Williams and Mike Szczys bubble sort the best hardware hacks so you don’t miss ’em. This week we’re smitten by the perfection of a telephone tape loop message announcer. We enjoyed seeing Blender’s ray tracing to design mirrors, and a webcam and computer monitor to stand in for triple-projector-based fractal fun. There’s a bit of injection molding, some Nintendo Switch disassembling, and the Internet on a calculator. We close the show with a pair of Space stories, including the happy news this week that Wally Funk finally made it there!

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)