AvoRipe Takes A Firm Grip On The Ultimate First World Food Problem

March 18, 2020 by 14 Comments

You don’t have to be an extinct mammal or a Millennial to enjoy the smooth, buttery taste of an avocado. Being psychic on the other hand is definitely an advantage to catch that small, perfect window between raw and rotten of this divaesque fruit. But don’t worry, as modern problems require modern solutions, [Eden Bar-Tov] and [Elad Goldberg] built the AvoRipe, a device to notify you when your next avocado has reached that window.

Taking both the firmness and color of an avocado as indicators of its ripeness into account, the team built a dome holding a TCS3200 color sensor as stand for the avocado itself, and 3D printed a servo-controlled gripper with a force sensor attached to it. Closing the gripper’s arms step by step and reading the force sensor’s value will determine the softness the avocado has reached. Using an ESP8266 as centerpiece, the AvoRipe is turned into a full-blown IoT device, reporting the sensor readings to a smartphone app, and collecting the avocado’s data history on an Adafruit.IO dashboard.

There is unfortunately one big drawback: to calibrate the sensors, a set of nicely, ripe avocados are required, turning the device into somewhat of a chicken and egg situation. Nevertheless, it’s a nice showcase of tying together different platforms available for widescale hobbyist projects. Sure, it doesn’t hurt to know how to do each part from scratch on your own, but on the other hand, why not use the shortcuts that are at our disposal to remove some obstacles — which sometimes might include programming itself.

Continue reading “AvoRipe Takes A Firm Grip On The Ultimate First World Food Problem” →

Join Team Hackaday To Crunch COVID-19 Through Folding@Home

March 18, 2020 by 85 Comments

Donate your extra computer cycles to combat COVID-19. The Folding@Home project uses computers from all over the world connected through the Internet to simulate protein folding. The point is to generate the data necessary to discover treatments that can have an impact on how this virus affects humanity. The software models protein folding in a search for pharmaceutical treatments that will weaken the virus’ ability to attack the human immune system. Think of this like mining for bitcoin but instead we’re mining for a treatment to Coronavirus.

Initially developed at Standford University and released in the year 2000, this isn’t the first time Hackaday has advocated for Folding@Home. The “Team Hackaday” folding group was started by readers back in 2005 and that team number is still active, so let’s pile on and work our way up the rankings. At the time of writing, we’re ranked 267 in the world, can we get back up to number 30 like we were in 2008? To use the comparison to bitcoin once again, this is like a mining pool except what we end up with is a show of goodwill, something I think we can all use right about now.

Continue reading “Join Team Hackaday To Crunch COVID-19 Through Folding@Home” →

A Practical Dual-Arm SCARA 3D Printer

March 18, 2020 by 24 Comments

We see a lot of 3D printers here at Hackaday, but as over the years the 3D printer has moved from being an exciting item in its own right to being an everyday tool, it’s increasingly rare for us to feature a build of one as a project. It’s especially rare for us to see a 3D printer that isn’t a variation of either an XYZ Cartesian design or a delta printer, but that’s what [bondus] has done with a printer based upon a parallel SCARA mechanism. If SCARA isn’t something you’re familiar with, it’s a design used in the world of industrial robots in which an almost humanoid jointed arm works in two dimensions, with the third being provided by raising or lowering the whole construction. It has the advantage of greater speed than Cartesian designs, at the expense of higher quality joints being required to maintain accuracy of positioning.

This is the second SCARA printer he’s built, and has a sturdy set of aluminium arms and substantial bearings. Drive comes via a pair of belts to some very large pulleys, and calibration is extremely important to ensure that both arms are in exactly the same plane. The curcular bed is on a lead screw that provides the Z axis.

The results are certainly impressive, both is speed and in print quality. We’ve placed a video of it in action below the break. Whether or not SCARA printers improve to the point of being ubiquitous isn’t something we can supply an answer to, but we’ve featured a small number of them in the past. Particularly memorable is this one using an industrial robotic arm.

Continue reading “A Practical Dual-Arm SCARA 3D Printer” →

Teardown: Cobra XRS 9740 Radar Detector

March 18, 2020 by 46 Comments

Drivers with a lead foot more often than not have Waze open on their phone so they can see if other drivers have spotted cops up ahead. But avoiding a speeding ticket used to involve a lot more hardware than software. Back before the smartphone revolution, that same driver would have had a radar detector on their dashboard. That’s not to say the gadgets are completely unused today, but between their relatively high cost (one of the top rated models on Amazon as of this writing costs over $300) and the inevitable false positives from so many vehicles on the road having their own radar and LIDAR systems, they’ve certainly become a less common sight over the years

The subject of today’s teardown is a perfect example of “Peak Radar Detector”. Manufactured back in 2007, the Cobra XRS 9740 would have been a fairly mid-range entry offering the sort of features that would have been desirable at the time. Over a decade ago, having an alphanumeric display, voice alerts, and a digital compass were all things worth shouting about on the box the thing was sold in. Though looking like some kind of Cardassian warship was apparently just an added bonus.

As the name implies these devices are primarily for detecting radar activity, but by this point they’d also been expanded to pick up infrared lasers and the strobe beacons on emergency vehicles. But false positives were always a problem, so the device allows the user to select which signals it should be on the lookout for. If you were getting some kind of interference that convinced the detector it was being bombarded with IR lasers, you could just turn that function off without having to pull the plug entirely.

But it’s important to remember that this device was built back when people were still unironically carrying around flip phones. Detecting laser and multi-band radars might sound like something pulled from the spec sheet of a stealth fighter jet, but this is still a piece of consumer electronics from more than a decade in the past. So let’s crack it open and take a look at what goes on inside a radar detector that’s only a few years away from being old enough to get its own driver’s license.

Continue reading “Teardown: Cobra XRS 9740 Radar Detector” →

Can A CPAP Fan Become A Ventilator?

March 18, 2020 by 137 Comments

Watching the hardware community respond to the global pandemic is a fascinating process, because of the breadth of projects being considered, and also because of the differing experiences and perspectives being brought to the table. Components most of us might have been unaware of are appearing, such as the CPAP blower used by [Jcl5m1] in his ventilator design.

He starts with a very necessary disclaimer against trusting a random person on the Internet on the subject of medical equipment design, and since it must be possible to do damage with an inappropriate ventilator we can only echo that. But as a CPAP user he’s familiar with their operation and parts, and he’s taken the centrifugal blower from one of them and paired it with a speed controller and an Arduino to provide an adjustable pressure.

What we take away from this is not in any way a ventilator that’s ready to be hooked up to sick patients, but an interesting look at ventilators in general, CPAP components, and the possibility that this project and others like it might eventually form the basis of something more useful if they attract the attention of people with more experience in the field. We’ve already seen 3D-printing used to make valves for a respirator at a hospital in Italy.

Hearing Plants Giggle Is Just As Creepy As You Think

March 18, 2020 by 13 Comments

While best known for Charlie and the Chocolate Factory, Roald Dahl wrote quite a few similarly oddball stories in his time. One of them, The Sound Machine, is about a device that allowed the user to hear the anguished screams of trees as they were cut down. Sounds kind of weird to us, but [Roni Bandini] liked the idea so much he decided to build his own version.

Now to be fair, the device doesn’t only scream in pain. In fact, most of the time it should be emitting laughs and happy noises. Using a moisture sensor driven into the soil of a plant’s pot, the device uses these audio cues to tell you the relative health of your leafy friend. So assuming you’ve got any sort of green thumb at all, things should be fine.

But once the soil gets too dry and the device determines the plant is in “pain”, things take a turn for the worse. We suppose it doesn’t technically scream out so much as grunt like a zombie, but it’s still not a noise we’d want to hear while walking through the house at night. Luckily, it seems you need to hit the button on the front of the 3D printed enclosure to get it to play the appropriate sound track from its DFPlayer module.

Personally we’d rather build something that makes sure the plants are being taken care of automatically than a gadget that cries out in anguish to remind us that we don’t know what we’re doing. But hey, everyone gets inspired in their own way.

Continue reading “Hearing Plants Giggle Is Just As Creepy As You Think” →

This Is Not An Argument Bot

March 17, 2020 by 41 Comments

While in-person arguments are getting harder to come by these days, we’ll always have the internet (hopefully). So what can you do to stay on your game in a time when a little levity is lauded? Build an argument bot and battle wits with the best — a stern-faced John Cleese!

This latest offering from [8 Bits And A Byte] refers to a Monty Python sketch featuring an argument service — an office with a receptionist who will take your money and send you down the hall for a healthy and heated discussion. If you’ve never gone on a Monty Python binge, well, it’s probably as good a time as any.

Electronics-wise, the argument bot is a pretty simple build. A Raspberry Pi B+ outfitted with a Google AIY hat listens to your side of things and decides which bones to pick. Your obviously misguided statements are then matched with DialogFlow intents, and dissent is sent back through the speaker. Meanwhile, Mr. Cleese’s jaw moves up and down on a printed and servo-driven linear actuator while he maintains a stiff upper lip. Before you go off on that Python binge, check out the build video after the break.

Have you seen what can happen two robots argue? ‘Tis but a scratch. Continue reading “This Is Not An Argument Bot” →