The greatest advantage to using the Arduino family of microcontrollers for DIY electronics projects, is that they are ubiquitous. Since they are so available, they are inexpensive and you can find open-source software to get started. If you’ve ever had the opportunity to work with an Arduino Uno microcontroller board, then you’ve probably executed the flashing LED example. Going further, you might attach a button, or switch, to trigger the LED or to turn it off making the project interactive. There are many sensors that could be connected to the Arduino Uno and setup to trigger events, such as the LED flashing, using threshold values that we would need to experiment with in order to figure out what settings work best for creating the effect we want.
What do plants actually require in order to grow well? It is important for context and it is important for every human to understand what it takes to grow plants, even if the future doesn’t allow for outdoor cultivation. At a minimum this is my effort to prevent future generations from suffering the fate of a World without plants as proposed by Mike Judge in his movie “Idiocracy” where people no longer understand why plants wouldn’t want to live on a beverage containing “electrolytes.”
A basic, low-cost, reliable, indoor garden is a controlled environment typically in the form of a tent inside a room, inside a garage. You have one or two AC-powered ventilation fans, recirculating and/or one is the intake and the other is the exhaust. You have two super bright fluorescent lamps connected to a mechanical/digital timer controlled AC outlet providing the plants with their appropriate light-cycle. Your plants are contained in soil, or a basic deep water culture hydroponics system. A large plastic reservoir with multiple grow baskets containing clay pellets partially submerged in the nutrient solution being aerated by an aquarium-style air-pump that’s connected to an air-stone, creating bubbles, preventing stagnation, keeping the culture healthy.
A "smart" garden uses electronics for the purpose of making decisions based on defined parameters and provides a more connected environment.
You value the project because you are able to customize and experience the process of its creation, both physically and mentally.
"TheDecider" was originally hardcoded with specific values that were fixed in place until I changed them in the Arduino sketch, recompiled, and uploaded. There are two types of decisions that TheDecider executes, timed-based, and sensor-based rules. The time-based rules simply compare the current time to the last time the appliance was turned-on or off. The sensor-based rules use a minimum value threshold and a maximum value threshold that are compared to the current sensor reading and then execute the corresponding action for the appliance. For example, if the temperature is below 55° then turn-off the ventilation fans; if the temperature is above 80° then turn-on the ventilation fans. Each appliance has corresponding rules for sensor reading thresholds, time-based automation, and a combination of both, priority depending on the order of the rules.
The hydroMazing controller is designed to operate ventilation fans for air circulation, water pumps, occasionally a humidifier, heaters, or any other appliance that is necessary to maintain an ideal environment for plants to grow. Typically, we DIY'ers would hook-up some relays to a microcontroller to achieve control. However, with hydroMazing, the system uses remote controlled wireless AC outlets, ensuring safer control than traditional relays. hydroMazing uses low-cost open-hardware modules and the ubiquitous microcontroller, the Atmega328, on an Arduino Nano*, offering the flexibility of customization and expansion. The sensor choices are endless, but I’ve narrowed it down to a few important and relatively inexpensive modules. A temperature and relative-humidity sensor, moisture sensors for soil, liquid temperature probe for hydroponics, a simple photocell. There are many other optional additions including the float switch or switches and flow-rate sensors.
Plants don't need access to the Internet to grow. So what can a Raspberry Pi 3 with built-in WiFi and bluetooth do for hydroMazing? A connected hydroMazing can let us know what is going on inside our garden through a web-interface, email, or even, text-messaging.
It was two years ago when I decided to try using an Arduino Uno microcontroller to replace my individual Lux WIN100 Heating & Cooling Programmable Outlet Thermostat. These outlets control an appliance, such as a small heater or, in this case, a ventilation fan. A device that is plugged into the outlet turns on... Continue Reading →