15. System integration
This week focused on developing the system integration of all electronic components for the final project. I began by designing the case to house the entire electronics section. The main goal at this stage was to organize all the components neatly and precisely within the case, ensuring easy assembly, stable operation, and easy access to essential elements.
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During the design process, I took the following into account.
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The size and shape of the components (microcontroller, sensors, pump, etc.).
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Methods for securing the elements inside the case.
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Access to components for setup and maintenance.
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A clean and logical arrangement of components.
Designing a well-thought-out case for the electronics is a crucial step in the integration process, directly affecting the reliability and ergonomics of the entire system.
Bill of Material
Here is the list of components I used.
| Components | Price |
|---|---|
| ESP32C3 Seeed Studio XIAO BLE WIFI module | $ 4.70 |
| PH meter | $ 4.70 |
| TDS meter | $ 2.05 |
| DS18B20 digital thermometer | $ 0.94 |
| Water Level Sensor | $ 1.33 |
| Water pump | $ 0.68 |
| Aerator | $ 2.13 |
| FitoLED | $ 4.41 |
First, I created the schematic by connecting the components together in KiCad.
After finalizing the sketch, I decided to use the following input devices for the project: pH meter, TDS meter, temperature sensor and water level sensor.
And for output, I used a water pump and an aerator.
I designed the enclosure in Rhino, while simultaneously measuring all the necessary dimensions to ensure accuracy and correct placement of all the components inside.
3D Modeling
For easier maintenance, since some sensors need periodic calibration, I created a separate removable module. It fits securely into its place but can be easily removed. The sensors are located in the center of the container to ensure stable operation and accurate measurements.
In addition, I designed special connectors for installing plant modules. The modules are inserted into the drainage hole and securely locked in place with a slight twist, which prevents accidental removal and makes installation easier.
The entire structure is mounted on the water reservoir and requires fixation with it — this part is still under development. The lid and the body fit tightly together, forming a double wall that prevents nutrient solution from entering the electronics compartment. To increase the strength of the connection, the lid and body are secured with bolts.
This is how the enclosure with the electronics will look at this stage. However, it still needs further refinement, as some parts, such as components for fixation and connections, still need to be purchased. Once all the necessary elements are available, I will be able to complete the assembly and final adjustments of the structure.
Printing
After completing the first version of the models, I decided to do a test 3D print of all the main parts and the enclosure. This was necessary to make sure that all components fit correctly in their designated places, align properly, and fit well within the structure. This approach helps to identify and fix any potential issues before final production.
Junction between the enclosure and the lid.
Module connection joint.
Removable module for input devices.
After installing the modules with sensors and the water pump, three separate compartments remain on the enclosure. One of them will be used to place the circuit board responsible for reading data from the connected sensors. The remaining two compartments are planned to be combined into a single space to house the control board that manages the entire system. This layout provides a logical and convenient internal structure, making the device easier to maintain and modify in the future.
The current placement of the water level sensor makes it difficult to insert the module into the nutrient solution reservoir. Therefore, the design will need to be slightly modified in the future to provide a more convenient location for mounting the sensor.
