Boost Your Garden’s Output Using Ultrasonic Mist

ultrasonic_aeroponic_growing_rig

If you enjoy gardening, it’s never too early to start thinking about next year’s growing season. [Jared Bouck] over at InventGeek loves his tomatoes, but the slow grow rates of his dirt-bound plants were less than impressive. To get things moving faster, he created a low-cost aeroponics system that uses ultrasonic mist to produce some pretty impressive results.

The construction process of this ultrasonic aeroponics rig looks dead simple, and [Jared] said that he had everything assembled in about half an hour. A cheap ultrasonic mister was mounted in the bottom of a plastic tub, and holes were cut in the tub’s lid to make room for his growing baskets. Tomato seedlings were wrapped in rock wool and placed in a clay growing medium, suspended over the water bath. The mister was turned on, and after just a few days, the results were obvious.

In the last step of his tutorial, he compares his aeroponically grown plant to one grown in soil – the difference is unbelievable. Considering how reasonably priced his setup is, it seems like a no-brainer to start growing your entire vegetable garden this way.

Color Changing Door Handles

This color changing door handle was made using a very simple manufacturing process. [Barmak] already had experience working with polyester resins when making passive component filled drawer pulls (he included a couple of pictures at the end of his post). The same process was used here except that instead making it from one solid chunk of clear resin he decided to use alternating layers of dyed resin.

The build begins with a mold made out of MDF. This material has a very smooth surface finish which will help with the final look of the door handle. Threaded rod is inserted through carefully placed holes in the side of the mold — these will serve as the mounting hardware when complete. He then pours thin coats of resin to build up the complete handle.

An RGB LED strip is incorporated in the side of the handle that will go toward the door. It seems like the wires to control the device pass through a hollow spacer surrounding the threaded rod. He makes some mention of using a 555 timer to control the colors, but there’s not much more information than that. Still, the reflected light is a unique feature if you’ve got a place in your home that needs to be spiced up.

Once you’re done, you can use any leftover resin to make your own project boxes.

Sous Vide Crock Pot Controller

Tempted by what sous vide cooking has to offer, but balking at the price for a unitasker, [Lee’s] father in law set out to see if he could rig up his own precision temperature controlled cooking system on the cheap. He immediately hit eBay and shelled out about around $75 to get his hands on a solid state relay, PID controller, and temperature probe.

As you can see above, a crock pot serves as the cooking vessel. We’ve seen this method before, either splicing into the power cord, or providing a single outlet on the controller. This version provides a PID controlled outlet to which the appliance can be plugged in. The other outlet in the socket is always on and powers an aquarium pump that circulates the heated water during the cooking process.

The result works quite well, even though it wasn’t a huge cost savings. There are a few issues with positioning of the temperature probe, but that may be where experience comes into play.

Video – Turning Good Gnomes Evil

Image of gnomes with glowing eyes

In this video [Jack] will show you how to take a garden gnome and a solar light to create a FrankenGnome that is sure to creep out your friends and neighbors. This Hackaday original video is the first in a new series of videos that we will now be posting on a weekly basis.

You’ll notice a few symbols at the beginning of these videos. These symbols are there to help you understand what the video is all about. In the upper left corner, we have the skill level. These will range from 1 for very basic projects to 4 for highly advanced projects. The upper right corner breaks the video into two categories. The first category is ‘feature adding’. In these videos we will be taking off-the-shelf items and modifying them to do something new. The other category is ‘skill building’. In these, we will be exploring different topics in depth. At first, the skill building videos will be mostly about electronics and software. In the future when we have excavated more room in Hackaday Headquarters, located deep beneath a mountain in remote [REDACTED], we will start doing videos showing you topics with a more mechanical nature. The other icons represent the major skills involved in the project.

Check out the video after the break.

Continue reading “Video – Turning Good Gnomes Evil”

Home Automation Systems Easily Hacked Via The Power Grid

x10_home_automation_hacked

As home automation becomes more and more popular, hackers and security experts alike are turning their attention to these systems, to see just how (in)secure they are.

This week at DefCon, a pair of researchers demonstrated just how vulnerable home automation systems can be. Carrying out their research independently, [Kennedy] and [Rob Simon] came to the same conclusion – that manufacturers of this immature technology have barely spent any time or resources properly securing their wares.

The researchers built tools that focus on the X10 line of home automation products, but they also looked at ZWave, another commonly used protocol for home automation communications. They found that ZWare-based devices encrypted their conversations, but that the initial key exchange was done in the open, allowing any interested 3rd party to intercept the keys and decrypt the communications.

While you might initially assume that attacks are limited to the power lines within a single house, [Kennedy] says that the signals leak well beyond the confines of your home, and that he was able to intercept communications from 15 distinct systems in his neighborhood without leaving his house.

LAN-connected Washing Machine Lets You Know When Your Clothes Are Done

lan_connected_washing_machine_laundruino

[Micha’s] washing machine is equipped with a rather inaccurate timer, so it is always difficult to estimate when the load will be finished. Since it is located in his basement, he hated having to check on the machine continually to know when his clothes were done. Instead of hauling up and down the stairs over and over, he decided to hack in an “end of cycle” notifier of his own.

The washer has an LED that lights when it is finally done doing its thing, so [Micha] removed the LED and soldered in two wires, which he then connected to his Arduino. When the washer is finished and the LED should be lit, the Arduino senses that the input has been pulled low, signaling the end of the cycle. The Arduino was hooked into his home network via an Ethernet shield, enabling him to monitor the process from the comfort of the nearest web browser.

It’s a clever implementation, and it sure saves him a lot of time trudging up and down the stairs. Nice job!

Air Conditioner Regulation Using A Hobby Servo

automatic_mechanical_ac_control

For anyone that works in a large office building, odds are you know the pains of dealing with a poorly regulated HVAC system. [Robovergne] and his co-workers recently moved to a new location, and found that the air conditioning control was less than effective, leaving the office as hot as a sauna or as cold as a meat locker.

While they manually triggered the A/C on and off every half hour for a while, that grew tiring, so [Robovergne] decided to take things into his own hands. He had never used an Arduino before, and figured that regulating the air would be a great first project. He mounted a small hobby servo onto the front of the A/C remote, and wired a DS18B21 temperature probe to the Arduino. A small pot is used to adjust the temperature setpoints, which are displayed on the attached LCD screen. Now, when the temperature starts to rise, the Arduino triggers the servo to turn the air conditioning on without human interaction.

[Robovergne] says that while his solution is ugly, it works quite well. It definitely gets the job done, we can’t argue with that!

Continue reading to see a video of his automatic A/C controller in action.

Continue reading “Air Conditioner Regulation Using A Hobby Servo”