Growing your own food is a fun hobby and generally as rewarding as people say it is. However, it does have its quirks and it definitely equires quite the time input. That’s why it was so satisfying to watch Farmbot push a weed underground. Take that!

Farmbot is a project that has been going on for a few years now, it was a semifinalist in the Hackaday Prize 2014, and that development time shows in the project documented on their website. The robot can plant, water, analyze, and weed a garden filled with arbitrarily chosen plant life. It’s low power and low maintenance. On top of that, every single bit is documented on their website. It’s really well done and thorough. They are gearing up to sell kits, but if you want it now; just do it yourself.

The bot itself is exactly what you’d expect if you were to pick out the cheapest most accessible way to build a robot: aluminum extrusions, plate metal, and 3D printer parts make up the frame. The brain is a Raspberry Pi hooked to its regular companion, an Arduino. On top of all this is a fairly comprehensive software stack.

The user can lay out the garden graphically. They can get as macro or micro as they’d like about the routines the robot uses. The robot will happily come to life in intervals and manage a garden. They hope that by selling kits they’ll interest a whole slew of hackers who can contribute back to the problem of small scale robotic farming.

[Dan Bowen] describes the construction of a backyard hydroponics set-up in an angry third person tirade. While his friends assume more nefarious, breaking, and bad purposes behind [Dan]’s interest in hydroponics; he’d just like some herbs to mix into the occasional pasta sauce.

Feel particularly inspired one day after work, he stopped by the local hardware store and hydroponics supply. He purchases some PVC piping, hoses, fittings, pumps, accessories, and most importantly, a deck box to hide all the ugly stuff from his wife.

The design is pretty neat. He has an open vertical spot that gets a lot of light on his fence. So he placed three lengths of PVC on a slant. This way the water flows quickly and aerates as it goes. The top of the pipes have holes cut in them to accept net baskets.

The deck box contains a practically industrial array of sensors and equipment. The standard procedure for small-scale hydroponics is just to throw the water out on your garden and replace the nutrient solution every week or so. The hacker’s solution is to make a rubbermaid tote bristle with more sensors than the ISS.

We hope his hydroponics set-up approaches Hanging Gardens of Babylon soon.

No longer content with adding value to the thermostat in the hallway or making your fridge smarter than it should be, IoT vendors are pushing into the inner sanctum of homes, the holy of holies – the bathroom. Sure, you can spend big bucks on an electronically controlled valve to turn your shower into a remote-controlled spa that shares your bathing habits with the cloud, but if you’re on a more modest budget and have the hacker spirit, you might want to check out this DIY automated shower valve with IoT features.

When we last ran into [TVMiller], he was opening gates using Jedi mind tricks, and before that he was shrinking a floating golf green to a manageable size. Such hacks work up a sweat, and while a clean hacker is a happy hacker, all that pesky valve-twisting and temperature-fiddling is so annoying. So with a few parts acquired from the waste stream, like an acrylic box, some salvaged servos, popsicle sticks, and a hell of a lot of caulk, [TVMiller] hacked together a feature-packed controller for his existing shower valves. An Arduino MKR1000 reads the water temperature and controls the servos that allow him to start the shower from his phone. Time and temperature data are sent to the cloud using ThingSpeak. You can see the whole thing in action in the mildly-NSFW video after the break.

Admittedly, this is a pretty janky setup, but it falls under the universal hacker disclaimer of “it’s just a prototype.” Still, we like the idea of retrofitting standard shower valves, and the popsicle-stick parallelograms for increasing leverage is a neat trick. We’ll be watching to see where this goes next.

It’s no secret that hackers like to measure things. Good numbers lead to good decisions, like when to kick your wastrel teenager out of a luxuriously lengthy shower. Hence the creation of this wireless Arduino-based water meter interface.

We’ll stipulate that “wireless” is a bit of a stretch. Creator [David Schneider] chose to split the system into two parts – a magnetometer and an Arduino to sense impulses from the water company meter, and a Raspberry Pi to serve the web interface. The water meter is at the street rather than in his house, so the sensor is wired to the Pi with some telephone cable. But from there the system is wireless.

[David] goes into some good detail on the sensing problem he faced, which relies on detecting the varying magnetic field due to the spinny-bits inside the flowmeter and cleaning up the signal with the Arduino; he also addresses aliasing errors that occur when flow rate approaches the sampling rate of the magnetometer.

We like the fact that there’s a lot of potential to leverage this technique to monitor other processes with rotating magnetic fields. And like this optically coupled gas-meter monitor, it’s not invasive of the utility’s equipment either, which is a plus.

[via reddit]

The lofty goal of making sure every school kid has access to a laptop has yet to be reached when along comes an effort to put a 3D printer in the hands of every kid. And not just any printer – a printer the kid builds from a cheap kit of parts and a little e-waste.

The design of the Curiosity printer is pretty simple, and bears a strong resemblance to an earlier e-waste 3D printer we covered back in December. This one has a laser-cut MDF frame rather than acrylic, but the guts are very similar – up-cycled DVD drives for the X- and Z-axes, and a floppy drive for the Y-axis. A NEMA 17 frame stepper motor provides the oomph needed to drive the filament into an off-the-shelf hot end, and an Arduino runs the show. The instructions for assembly are very clear and easy to follow, although we suspect that variability in the sizes of DVD and floppy drives could require a little improvisation at assembly time. But since the assembly of the printer is intended to be as educational as its use, throwing a little variability into the mix is probably a good idea.

The complete kit, less only the e-waste drives and power supply, is currently selling for $149USD. That’s not exactly free, but it’s probably within range of being funded by a few bake sales. Even with the tiny print volume, this effort could get some kids into 3D printers early in their school career.

[Husham] not only likes his electronics projects but clearly enjoys documenting them as well. He’s written a nice Instructable on a Temperature Data Logger that he has built and thankfully makes his code available for others to use. The end product is cleanly designed and made for weather-proof outdoor applications.

As you may expect, the brains behind this operation is an Arduino. It is coupled with a Real Time Clock to maintain accurate timing as well as an SD Card Module which is used to store the data collected. In this case, the temperature is read by a LM35 temperature sensor and that value, along with the time, is recorded to a .csv file on the SD card in one minute intervals.

There is also an LCD screen that displays the date, time and current temperature. To save battery life the LCD backlight is normally off. It can be turned on using a magnet that interacts with a hall effect sensor on the top of the case. This worked so well that [Husham] installed a second hall effect sensor on the side of the case that resets the Arduino. Speaking of the case, it is a weather proof PVC electrical box with a conduit adapter installed on the bottom side. A battery pack made up of two used laptop cells housed in a piece of conduit supplies 7.2 volts to the Arduino and other components. Unfortunately, there’s no word on how long the battery pack lasts. Once the data is logged, the SD card can be removed and the .csv file opened in spreadsheet software to make a graph showing temperature change over time.

It’s great having fresh vegetables just a few steps away from the kitchen, but it takes work to keep those plants healthy. [Pierre] found this out the hard way after returning from vacation to find his tomato plant withering away. He decided to put an end to this problem by building his own solar-powered plant watering system (page in French, Google translation).

An Arduino serves as the brain of the system. It’s programmed to check a photo resistor every ten minutes. At 8:30PM, the Arduino will decide how much to water the plants based on the amount of sunlight it detected throughout the day. This allows the system to water the plants just the right amount. The watering is performed by triggering a 5V relay, which switches on a swimming pool pump.

[Pierre] obviously wanted a “green” green house, so he is powering the system using sunlight. A 55 watt solar panel recharges a 12V lead acid battery. The power from the battery is stepped down to the appropriate 5V required for the Arduino. Now [Pierre] can power his watering system from the very same energy source that his plants use to grow.

[Instrument Tek] isn’t messing around with a hobby-sized greenhouse. In fact if it were any bigger we’d call it a commercial operation. But what interests us is the professional-quality greenhouse automation he built around and Arduino board.

The greenhouse is about what you’d expect to see at a nursery, except the footprint is somewhere around 10′x10′. It’s a stick-built frame with walls made of poly. Professional greenhouses monitor and regulate temperature and humidity and this one does just that. The video after the break starts off by showing the controller box. It has temperature, humidity, and light sensors that allow the Arduino to judge growing conditions. If it gets too hot, some slats are opened and a fan exhausts air from the structure. If it gets to cold, a series of light fixtures are energized. They contain heat lamps, as this setup is in northern Alberta, Canada and it can get quite cold some nights. The drip system is also automated, with a solenoid to turn water on and off.

In addition to that 3:26 show-and-tell, we’ve embedded a 27-minute video that shows how to build the controller box. So you can start you plants indoors on the rack, then populate the greenhouse when they get large enough.

[Thanks Ricardo]

Starting your garden indoors helps to ensure large yields. This is because the plants get a head start before it’s warm enough for them to be put in the ground. But the process involves a fair amount of labor, ensuring that the lights are turned on and off at the right times each day, and that the temperature for germination and growth, as well as humidity, hit a certain target. It’s obvious that a bit of automation would be nice, and this Arduino-based garden nursery does just that. One of the things that sets this project apart is that it shows you how to go from an empty room to the bounty of plant starters seen here.

For the most part the equipment is what you’d expect, seed trays and covers, tray warming mats, and fluorescent light fixtures. the whole thing is given a small footprint thanks to an adjustable shelving unit. The Arduino is used in conjunction with a Sprout Board to add connectivity for switching the lights and warming mats. This is just a matter of driving a relay to switch mains voltage and can take any number of forms, including this home automation project we saw the other day.

[Thanks Tom]