For this project, we figured we'd simply use the sun to further help an organism that already uses it - a plant. We used the sunlight to store enough energy to rotate a base, as well as measure the water level in the soil, as shown by a servo motor.
We did begin with a "simple" BEAM circuit... which we couldn't quite get working. This is mostly because we also had to power up the computational aspect of the project - the Arduino Micro. And we needed a specific voltage level. Nonetheless, through this process we did find the minimum voltage and amperage needed to power the motor - this was 3.5V 200mA.
We also had a little trouble with the design, but after we messed around with it a little, we were able to come up with a suitable concept that would house our materials, as well as provide stability to the plant. Future designs would have more solar panels, less wiring, more easier battery application and removal. Indicators of battery health. Or even no battery at all. I would like to figure out the BEAM circuit, but that will have to wait. Nonetheless, we ended with a nice final product!
Our earlier circuits (left) were also quite complicated, while by featuring a battery storage solution, we could afford a much simpler system (above). The pink wire here symbolizes the battery input. Notice the Arduino is now connected, along with the sensor, motor, and servo.
Once we determined the basic necessities of the circuit, we tested it rotating. Eventually we determined to invert the piece, and put the motor with the rotor facing down, so that we had no need for a slip ring in the final design.
I then had to make an enclosure for the piece, I chose to use a hexagonal design of CNC cut stacked ply, the design and process of which can be found here. This worked well since my Subtraction midterm was a CNC project.
Arnav was kind enough to help me with a solar panel. In order to replace the charge controller, and connect the battery we had on hand to the solar panel, I had to solder and connect some stuff, but once I did, I tested it, and it seemed to work. Then I connected it all to the board, and lo and behold, it worked!
The whole piece getting ready to fit together, a little varnish and it looks so nice. So glad the piece fit together so perfectly.
In future iterations I would prepare the sides more, perhaps build and prepare a pot just for this purpose, so the whole thing was more fluid. But still, for now, it works!