In the style of Garduino, I have started a project to help automate gardening. There are controllers on the market for doing this, but they are currently very expensive:
I would like to design a product which can provide these features, AND control lighting, AND have a bluetooth / remote interface… AND be half the cost.
This will be a system to control fan-speed control, ventilation, LED lights, temperature, humidity and CO2. The brains of this unit is the Bluetooth Bee Standalone.
AC Fan-Speed Control:
This system should be able to control cooling for the lighting system and ventilation for the main greenhouse space; this can be accomplished using just 1 fan, a y-duct adapter and an electronic duct damper. This will require a small mechanical relay. The fan speed itself will need to change depending on the temperature, humidity and CO2 levels. I was thinking of using a Triac or a Variac for this. A triac controller is cheaper, but variacs are able to slow a fan without causing it to hum. Advice needed on this point. Controlling DC fans is a lot easier – but I am not familiar with DC fans for inline ducts.
CO2 Control, Water pump control
Simple mechanical relays can be used to control the CO2 generator and hydroponic water pumps.
Ideally, this system will be able to control 300W of LEDs. 2 x 100W RGB LED and 100W of 120/m RGB strip lighting. The 100W LED diodes are composed of 440:430:630:660:535 crystals in a ratio of 2:1:5:1:1 – currently sourcing these from JXGLED in Shenzhen for $98 each (if you can help me negotiate a better price for sample LED diodes, let me know!). The LED strip lights are for under or side canopy lighting, and for germination / seedling lighting.
The 440 and 430nm crystals are for the growth of seedlings and vegetative growth - while the 630 and 660nm lights are for when the plant is in bloom or fruiting. The 535nm light is for the convenience of the gardener; green combines with red and blue to create a more natural white-ish light - which is important for ascertaining the health of one’s plants. In addition, green light does not affect a plant’s “sleep” during the dark photoperiod.
I am hoping that I can control at least 5 discrete lights using just one LED driver. The specifications for the 100W LED are Blue: 30-36V/1400mA Green:30-36V/350mA Red:20-26V/1750mA
Air Temperature + Humidity sensing is provided by the standard Grove T&H sensor. Water temperature (for hydroponic reservoirs) can be sensed using a cheap temperature chip and some silicon sealant. It looks like I will be doing the CO2 sensing using a MG811. I am hoping the price for this component will drop.
This system should be fully controllable both remotely over bluetooth, and locally using a dial/buttons and a green LCD.
All of these components will be tied together by the Bluetooth Bee Standalone + an RTC chip.