Students’ Leaf Blower Suppressor To Hit Retail

Electric leaf blowers are already far quieter than their gas-powered peers, but they still aren’t the kind of thing you’d like to hear first-thing on a Saturday morning. Looking to improve on the situation, a group of students from Johns Hopkins University have successfully designed a 3D printed add-on that manages to significantly reduce the noise generated by a modern electric leaf blower without compromising the amount of air it’s able to move. The device has proven to be so successful in tests that Stanley Black & Decker is looking to put a commercial version of the device on store shelves within the next two years.

The team says the first part of the problem was identifying where the noise was actually coming from. After taking an example leaf blower apart and studying all of its moving components, they determined that most of the noise produced wasn’t mechanical at all — what you’re actually hearing is the complex cacophony of high-speed air rushing out of the nozzle. With this knowledge in hand, they isolated the frequencies which were the harshest to the human ear and focused on canceling them out.

Continue reading “Students’ Leaf Blower Suppressor To Hit Retail”

Adaptive Chef’s Knife Provides Better Leverage

[Colleen] struggled with using a chef’s knife to cut a variety of foods while suffering from arthritis in her wrist and hand. There are knives aimed at people with special needs, but nothing suitable for serious work like [Colleen]’s professional duties in a commercial kitchen.

As a result, the IATP (Illinois Assistive Technology Program) created the Adaptive Chef’s Knife. Unlike existing offerings, it has a high-quality blade and is ergonomically designed so that the user can leverage their forearm while maintaining control.

The handle is durable, stands up to commercial kitchen use, and is molded to the same standards as off-the-shelf knife handles. That means it’s cast from FDA-approved materials and has a clean, non-porous surface. The pattern visible in the handle is a 3D printed “skeleton” over which resin is molded.

Interested? The IATP Maker Program makes assistive devices available to Illinois residents free of charge (though donations in suggested amounts are encouraged for those who can pay) but the plans and directions are freely available to anyone who wishes to roll their own.

Assistive technology doesn’t need to be over-engineered or frankly even maximally efficient in how it addresses a problem. Small changes can be all that’s needed to give people meaningful control over the things in their lives in a healthy way. Some great examples are are this magnetic spoon holder, or simple printed additions to IKEA furnishings.

This Arduino Is Feeding The Fishes

Depending on the species, a fish can be a fairly low-maintenance pet. But of course even the most laid back of creatures needs to eat, so you’ll have to make sure to feed them regularly. If you’re a fish owner who would like to simplify tending to your creatures, you might find value in this project from [CrazyScience].

This fish feeder is based on an Arduino Uno, the 8-bit microcontroller development board which has done so much for so many. The Arduino drives a stepper motor, which rotates a 3D printed disc mechanism for dispensing food. Each slot of the disc is loaded with a small amount of fish food, so that when it rotates, a slot dumps its contents through a slot into the water.

Activating the system is as easy as a wave of the hand. That’s thanks to an ultrasonic sensor, which detects movement close by, and triggers the food delivery mechanism in turn. We’d love to see this upgraded with a timer mode too, though it would require the addition of a real-time clock module to the humble Arduino Uno.

It’s a simple project, but one that teaches all kinds of useful skills, from programming to design and 3D printing. We just worry that the fish bowl in the demo is a far too small for fish to remain healthy. We’ve seen some other similar projects before, too.

Continue reading “This Arduino Is Feeding The Fishes”

2024 Home Sweet Home Automation: Spray Bottle Turret Silences Barking

Ah, dogs. They sure like to bark, don’t they? [rrustvold]’s dog likes to bark at the door when a package arrives. Or when someone walks by the house, or whenever the mood strikes, really. To solve the barking issue, at least near the front door, [rrustvold] built a spray bottle turret to teach the dog through classical conditioning.

As you can see from the image, it’s all about pulling the trigger on a standard spray bottle at the right time. This machine only sprays when two conditions are met: it hears noise (like barking) and detects motion (like overzealous tail wagging). It also has heat-seeking abilities thanks to a Raspberry Pi thermal camera.

To do the actual spraying, there’s a DC motor mounted behind the bottle which turns a pulley that’s mounted to its shaft. Around the pulley is a string that wraps around the spray bottle’s trigger. To complete the build, everything is mounted on a lazy Susan so there’s nowhere for Fido to hide-o.

If you’ve a dog whose bite is worse than its bark, consider building a custom dog door to keep it out of the cat box.

The 2024 Home Sweet Home Automation contest has officially wrapped — we’re counting the votes now, so stay tuned for an announcement about the winners shortly.

A Smart Power Distribution Unit For Home Automation

Power distribution units, as the name implies, are indispensable tools to have available in a server rack. They can handle a huge amount of power for demands of intensive computing and do it in a way that the wiring is managed fairly well. Plenty of off-the-shelf solutions have remote control or automation capabilities as well, but finding none that fit [fmarzocca]’s needs or price range, he ended up building his own essentially from scratch that powers his home automation system.

Because it is the power supply for a home automation system, each of the twelve outlets in this unit needed to be individually controllable. For that, three four-channel relay boards were used, each driven by an output on an ESP32. The ESP32 is running the Tasmota firmware to keep from having to reinvent the wheel, while MQTT was chosen as a protocol for controlling these outlets to allow for easy integration with the existing Node-RED-based home automation system. Not only is control built in to each channel, but the system can monitor the power consumption of each outlet individually as well. The entire system is housed in a custom-built sheet metal enclosure and painted to blend in well with any server rack.

Adding a system like this to a home automation system can simplify a lot of the design, and the scalable nature means that a system like this could easily be made much smaller or much larger without much additional effort. If you’d prefer to keep your hands away from mains voltage, though, we’ve seen similar builds based on USB power instead, with this one able to push around 2 kW.

Custom Dog Door Prevents Culinary Atrocities

Riley, an 8 lb pug, has more beauty than brains, and a palate as unrefined as crude oil. While we hate criticizing others’ interests and tastes, his penchant for eating cat poop needed to stop. After a thorough exploration of a variety of options, including cat food additives that make its excrement taste worse (HOW? WHY? Clearly taste wasn’t the issue!), automatic litter boxes that stow the secretions, and pet doors that authenticate access to the room with the litter box, [Science Buddies] eventually settled on a solution that was amenable to all members of the family.

The trick was in creating a door mechanism with a blacklist of sorts rather than a whitelist. As the cat didn’t like to push the door open itself, the solution needed to have the pet door open by default. A magnet on Riley’s collar would trip a sensor attached to an Arduino that would control servos to swing the door shut immediately if he attempted to access the defecated delights. Of course safety was a consideration with the door swinging in Riley’s face.

We’ve covered a few pet screeners, including one for the same purpose that used IR sensors (but a much bigger dog also named Riley), and a flock of solutions for chickens. We’ve also seen [Science Buddies] in previous posts, so they’re not on the tips line blacklist.

Continue reading “Custom Dog Door Prevents Culinary Atrocities”

The Future Looks Bleak For Alexa Skill Development

While the average Hackaday reader is arguably less likely than most to install a megacorp’s listening device in their home, we know there’s at least some of you out there that have an Amazon hockey puck or two sitting on a shelf. The fact is, they offer some compelling possibilities for DIY automation, even if you do have to jump through a few uncomfortable hoops to bend them to your will.

That being said, we’re willing to bet very few readers have bothered installing more than a few Alexa Skills. But that’s not a judgment based on any kind of nerd stereotype — it’s just that nobody seems to care about them. A fact that’s evidenced by the recent revelation that even Amazon looks to be losing interest in the program. In a post on LinkedIn, Skill developer [Mark Tucker] shared an email he received from the mothership explaining they were ending the AWS Promotional Credits for Alexa (APCA) program on June 30th.

Continue reading “The Future Looks Bleak For Alexa Skill Development”