IKEA hydroponics - First sensor for ambient light

Sensor measures light intensity for the plants

Lights sensor BH1750FVI connected to a ESP8266

The first sensor for my IKEA hydroponics project is a ambient light sensor (BH1750FVI) which will measure the light intensity on the plant bed in both the seed and cultivation unit. It is currently connected to an ESP8266 - a DIY-friendly and hacker-famous microcontroller with WiFi on board. I wrote a library for the light sensor which works with both Arduinos and ESP8266. You can find it here.

Germinated seeds in cultivation unit

The example sketch in the repository currently measures only the actual value of the ambient light. In future versions this sensor will be responsible deciding if and how long the IKEA LEDs have to be switched on depending on the overall light which fell on the plants. There will also be an uplink to a web-service (like Thingspeak or adafruit.io) where all the values are monitored in real time on a nice looking dashboard and will be accessible from everywhere.

In the meantime the seeds that germinated changed their habitat to the cultivation unit.

 

ESP8266 breadboard adapter board

This is an old design of the breadboard adapter. Please look at this blog post for the recent design.

I designed a single-sided ESP-12/ ESP-07 breadboard adapter PCB which will be easy to etch and solder for anyone who loves to play with the ESP8266 on a breadboard like me.

Eagle files are in my github repo

Features are:

* Fits ESP-12 and ESP-07 module
* Single-sided self-etchable design
* Few, cheap parts in SMD
* Breadboard-style - one row on each side accessible
* Vin >4.5V (max. 7V) input possible with 3V3 onboard voltage regulator (with two capacitors 10µF)
* Power-indicator LED
* (Schottky-) Diode as reverse polarity input protection possible (solder 0 Ohm resistor or just connect the two pads for no protection)
* RST, CH_PD, GPIO0 with 4k7 pull-up resistors on board (resistors can be omitted if remote access of those GPIOs is needed)
* GPIO15 with 4k7 pull-down (see above)
* Tactile switch connected to GPIO0 to get into flash mode
* Single post for 3.3V output near voltage regulator

Parts needed:

• 1x Voltage Regulator (e.g, AMS1117-3.3V, 800mA)
• 2x 10µF SMD ceramic capacitors
• 4x 4.7k SMD Ohm resistors
• 1x 330 SMD Ohm resistor
• 1x SMD-LED (1006)
• 1x 4*4mm SMD tactile switch
•  2x 1*8 pin header (pitch 2.54mm)
• optional: 1x Schottky-diode SMD

This is the actual revision 1.0 - improved for:

* Antenna part now protruding the PCB (no traces below antenna)
* Wider traces
* Schottky diode for reverse polarity protection
* 2x 10µF ceramic caps for input/ output of AMS1117
* Single post for 3.3V Output near voltage regulator