In this great part 1 (of 2) blog post by Lucky Resistor he walks through designing a ‘cheap plant watering sensor’ project. These are a very common project and are frankly a dime a dozen for whatever platform you’re inclined to design with. For instance we have this CC3200 LaunchPad-based project in the Learn System; Luke Iseman’s Garduino goes back several years now (built with Arduino, no doubt – see here & here); even Popular Mechanics are in on this primer maker project!
But what I really like about the ‘project’ at Lucky Resistor is the thoroughness for deconstructing the project to its step-by-step needs, and concluding why this or that decision was made to progress with this or that component or approach. It’s a really helpful guide – even if you don’t plan on making this project – for helping resolve your own design thinking needs and decisions. And of course it’s a cool project to boot! (That also happens to use some Adafruit tech for the prototyping phase 🙂 )
In this article I will talk about how I designed a cheap plant watering sensor. My goal is some kind of meta tutorial, where you can see the steps involved from the initial idea to the final sensor. If you ever planed to create a own device, I hope this article give you some inspiration to start your own project soon.
I have a couple of plants in flowerpots and this plants not only like some light, they also need water from time to time. Watering this plants is something I often forget, with sad results. There are ready made solutions for this, but I have some objections with all of them. To be clear: There are really smart products out there – it is absolutely nothing wrong with them. It is just as I like to build my own fan controller, I like to build my own plant watering sensor in my very own fashion.
Featured Adafruit Products!
SMT Breakout PCB for SOIC-8, MSOP-8 or TSSOP-8 – 6 Pack!: Beguiled by a fancy new chip that is only available in a SOIC or MSOP/(T)SSOP pinout? This breakout PCB set will make your life much much easier and get you prototyping faster than ever. One side has a 8-TSSOP/8-MSOP pin out with traces going to two rows of 0.1″ spaced holes, the other has 8-SOIC. Solder your chip to either side and you’re ready to rock on any solderless breadboard. Read more.
SMT Breakout PCB Set: The VCNL4010 sensor is a nice way to add a small-distance proximity sensor to your microcontroller project. For longer distances (in the range of cm, you can use a SHARP IR distance sensor, but those are only good if the object is over 10 cm away. The VCNL4010 is designed for much shorter distances, no more than 200mm (about 7.5″) and under our experimentation we found it worked best at distances of about 10-150mm. It would be good for say detecting when a hand moved nearby, or before a robot smacks into a wall. The sensor also has an ambient light sensor built in. Read more.
The SMD adapter breakout boards from Adafruit are the best I worked with so far. There is nothing fancy about them (special grooves or other “features” some of these adapters provide), but they are cheap and very well designed (and nice paneling).
I am actually also use the Adafruit Feather platform a lot for prototyping and testing. They have a very good size, so you can attach them to a device prototype to do some long term measurements.
Thanks Lucky Resistor for chiming in, and of course for sharing your project in the first place 😀