I've assembled the first prototype hanging planter and the sensors, so now it's time to put the two together!
(I've also noticed that the web application I'm using has problems with rotating images uploaded from my phone so I've taken the time to export these images so they're for sure oriented correctly.)
Here's a brief rundown on the hanging planter prototype I've assembled:
Here's the window. I also removed the blind.
The window itself was pretty dirty, so I used windex to clean it.
I needed to install brackets to hold the blinds I took down. A short trip to Home Depot and a few machine bolts, washers and nuts later and presto. I've stood the blind off by about 7 inches.
Here's a closeup of the brackets in question. As you can see, I used machine screws to fasten the bracket for the blind to a short length of angle bracket I cut to length.
I also picked up some 1/16 aluminum aircraft cable with a bunch of crimp sleeves as well as a screw hooks to attach the cable to. These basically just screw into some 1x4 I picked up and cut to the width of the window with about a 1/2" on both sides for the screw hooks to fit onto.
Here's a shot of the mount for it at the top. This is a temporary solution until I figure out how well it works under weight.
Here I've used metal strapping to fasten the 1/16 aluminum aircraft cable to the sides of the 1x4 boards. They're spaced about 15" apart for now. Once I've determined how high the plants grow until they can be harvested I'll adjust the height accordingly.
Here's a closeup of the strapping I used. It essentially just pins the cable to the board. It's not the best solution, but until I think of a better solution it should do for now.
So, this is the seedling tray. I've sown spinach and lettuce for now. Once they sprout, I'll put 'em in 18" trays that will sit on the 1x4 boards. I will also be using 1/16 aluminum aircraft cable to hold the trays in place.
Finally, here's a prototype for the agi-esp8266 sensor. It will measure temperature, humidity and ambient light. I also picked up an electronic timer which will control power to LED grow light's which will be mounted on the bottom of the 1x4.
A lot of folks will consider that to be a dumb solution, but to be honest it's the safest. Plugging uncertified electronics into your home electricty is a really bad idea. There is a reason we have electronics sent to be underwritten by the Underwriters Laboratory for testing under a variety of conditions.
Following local and national electrical codes is no joke. Do not fuck around with 120VAC.
Serious warnings aside, I think my solution is rather elegant. It's simple. UL listed electronic timers are affordable and there's no need to mess around with househould voltage.
I had a co-worker recently joke about 120VAC not being "high voltage". While it may not count as the sort of "high voltage" electricians talk about, do not under any circumstances mess around with your household mains electricity.
Down the road, I'll be looking at getting the equipment I'm working on certified but until then; I'm sticking to stupid simple technology that is proven to be safe.
This means I'm relying on conventional technology for the LED lighting and the mechanism for controlling it and I'll be using low voltage, battery powered devices for the sensors. The risks there are minimal, except perhaps for erroneous RF emissions which can also be easily rectified.
So, that in a nutshell is the prototype I will be working with this summer.
I'll be looking at streamlining this into a design that can easily be flat packaged for sending up north that folks can adjust to the size/dimensions of their windows.