July 20, 2018
Since the last installment in this Indoor Agriculture series, I’ve assembled the robot and began the testing phase. This phase consisted of growing, improving the software layer, and modifying the hardware design. Growing is definitely is the most difficult part. I lack a green thumb but I suspect that I can grow one 😉.
With the help of a local 3D print shop, I was able to manufacture the remaining components. It took a lot of work, but I was able to assemble the rest of the robot.
Looking back, I should have printed the CAD model on paper and assembled that first. Doing so would have helped me detect the following issues: a. The back plate is too small and does not provide enough room for mounting electronic components. b. The reservior is shorter and wider than it needs to be. The footprint could be reduced by making it taller and narrower. This would also result in an ultrasonic fogger that is submerged more.
During my “dry” runs I found that the software didn’t run as desired. It script was single threaded which prevented proper toggling of the grow lights and the ultrasonic fogger. Additionally, the schedulers weren’t activating at the right times. I had to make some adjustment before the software worked as desired.
The growing process is new to me. I’ve tried to grow plants in the past and have always failed. It’s very differant than writing software… the iteration cycles are far longer!
I started with a random assortment of seeds I acquired from a garden herb kit. These were pretty old so I wasn’t too sure if they would still germinate. I read about a germination technique which utilized a plastic bag and a moist paper towel. I gave it a shot and after a week in sunlight, I started to see seedlings form.
I was pretty stoked and transplanted them all into Rockwool. Looking back, I should have let them germinate until the seedlings were more mature.
Now that I had seedlings to test my machine with, I needed to mix the nutrient solution. I did this by:
This took several tries before I got a mixture which I was comfortable with. READ AS: got fed up and said YOLO.
After running the robot for 2 days, I shut it down and drained the reservior 😔. I ran into 3 problems:
You can’t win them all. Time to try again 🌿.
Written by Peter Chau, a Canadian Software Engineer building AIs, APIs, UIs, and robots.