Measure Climate Change with Hydroponic System Blog #4 | Sunlight Sensor and Water Purity

Recap

1. Measure Climate Change with Hydroponic System Blog #1 | Concept Design and Plans

2. Measure Climate Change with Hydroponic System Blog #2 | XMC4200 Bring-up and Hydroponic System

3. Measure Climate Change with Hydroponic System Blog #3 | XMC4700 + DC Motor Shield with Hydroponic System

Highlights

This time, i added a couple of sensors to the hydroponic system. Also, I invited some duck and car for entertainment .

Here is a list of the highlights of Measure Climate Challenge #4 blog.

1. Add more sensors to XMC4700 Relax Kit on Visual Studio Platform IO

a. Sunlight Sensor

b. Water Level Sensor

c. TDS (Total Dissolved Solids) Sensor

2. Power Supply Automation by Python

3. Measure TDS, Water Level, Sunlight related parameters

This picture below is the current setup! To test the water level and TDS value effectively, one small glass of water with Basil was used for the experiment over 1 week.

Details

1. Adding more sensors

I added a Sunlight Sensor, TDS Probe, and Water Level Sensor. For ease of wiring, I purchased the Grove Arduino Uno Shield. This is cheap but does the job very well. I only need one but bought two because the shipping cost was expensive The details are summarized on my website here https://green-scientist.com/2020/08/22/grove-arduino-uno-base-shield-with-infineon-xmc4700-relax-kit-and-motor-shield/ .

You can see water bubble from the air stone inside the glass. There are TDS probe and water level sensors.

For accurate measurements, the water level sensor needed to be wiped periodically with a kitchen paper. Otherwise, it stopped showing the correct water level value and just returned zero This sensor needs extra care ...

Unprofessional engineering notes are listed for the sensors below.

Sunlight Sensor Learning: https://green-scientist.com/2020/08/18/sunlight-sensor-with-si1145-and-arduino-platform-io/

Water Level Sensor Learning: https://green-scientist.com/2020/08/23/grove-water-level-sensor-with-arduino-xmc4700/

2. Python Automation

As the system becomes bigger, I wanted to have some automation for power-on, power-down sequence and testing. Python is used for automation of this hydroponics project. Within MS Visual Studio Code, Jupyter Notebook can be plugged in to run the sections of codes. This is very useful during debugging.

The code below is to program Siglent Power Supply SPD3303 for the Infineon DC Motor Controller Shield as the input voltage. This motor controller turns on and off the air pump for the hydroponic system automatically.

3. Testing

With the XMC4700/Arduino Serial Port, the sensor values were recorded and displayed every 3 seconds.

Here are measurement logs on Serial Port Console.

8/23/2020

This was the water level about a week ago. By eye inspection, the water level is about 80cm. This matched with the above log from the hydroponic system.

After about 1 week of the measurements, TDS value increased by ~ 10% and water level went down 15 % (= 15 cm)

8/28/2020 log

This is the comparison table between 8/23/2020 and 8/28/2020.

According to aquasana.com, TDS value between 0 and 100 is ideal. So far, the water quality seems very good

Next Steps

I would like to add air flow and the Infineon 3D sensor to control the air circulation. I would like to monitor the environment around the hydroponic system to understand the behavior more