I came across this place while researching how to setup the SI7021 which I found as an accurate humidity sensor that seemed to be more water resistant than DH22's from what information I turned up. Until finding this place, I was expecting to have to run things through wires somehow, but now that I've seen how small a wireless/battery operated...well, that seems easier.
The enclosure is only roughly 7' x 2' x 2.5' and glass; that won't affect RF overmuch? How much 'in the open' does the SI7021 need for readings- there is going to be a misting/watering system. So far what I have in my head is placing four in the place (I've seen a couple examples of a small box with the nano w/RF) with some way of attaching them to the background or wall while covering it up as much as possible with corkbark/rock. Ultimately sending info to a RPi and hopefully putting data into a mySQL similar for use similar to how http://www.raspiviv.com/ has things.
Sorry if this is the wrong area, it seemed the best place to throw this out there. I appreciate any assistance- I'm not incredibly savvy on hardware. Far more comfortable on software and fiddling around. This seems to be a very...uncommon meeting of vivarium and tech. This is discounting my heating/lighting/rain/weather/seasonal sync plans with its native habitat. The more I can control logically rather than having to manually adjust dials, the better.
I don't know the subject but mysensors+rpi2 should be the best choice in your case.
heating/lighting: this is on/off, no variator I guess ? light can be RGB
rain: rain gauge or open/close watering (which is on/off)
weather: Temp, Hum, Lux maybe
seasonal: by programming your season's parameter
Re Heating: So far my plan is to wire up something like this SSR with the assistance of a local electrician I've talked to. Its two ceramic heating elements, one 200W and another thats probably going to be 100W but I won't know until I am further along in building things and can test.
Re Lighting: I've got a quote on some strip LEDs which are going to be wired in with the assistance of an electrican. Two circuits, one at 4200K colortemp, other at 6500K, with varied brightness for a full dawn/day/dusk/night cycle. I /really/ don't like touching mains power...
Re Weather: I had not thought of having something to measure lux inbuilt on, but as the inside of the vivarium is going to be living (Live plants, soil, insects, and the Snake) I was not aware of how rugged sensors can be. Most projects I found poking around look to have setups inside houses, but I was hoping someone might be able to shed some light on how well putting the sensors in a place where water is being regularly misted. The closer I can put them to where I want (one soil level hotside, one 1/4 away in, 1/2 way up back hotside, and essentially the some on the cool side but the higher up one on the front) the better I can ensure the environment stays within the snake's tolerances (roughly 82-90F, 60~80% RH)
Re Weather: I had not thought of having something to measure lux inbuilt on, but as the inside of the vivarium [...]
Be carefull on how much energy will go through those relays, I do not see it on the page.
For leds, I don' know for sure, I have only an aquarium well planted, but quantity of light is critical to some plants, so be careful on this but you may already know.
From what I saw on the relay I linked, they handle up to 2A which is below what the 200W/110V CHE max and that won't be driven at full power anyway. If I do see a board with 4 SSRs that can handle a bit more amp without too much higher cost, I'll likely go to it just for extra safety.
At full output the LED's (with just the daylight) should be in the ballpark of 4K Lux (80+ CRI is their rating which looks to work well enough for my purpose and for the health of those in the vivarium...on paper atleast.), and that is being a bit optimistic, which put it in a full day, non direct sunlight. Since his natural habitat is forest-y ground, I'm not concerned with getting up to 10~15K Lux. I've also cared for some carnivorous plants, so I'm not too concerned on that front.
be carefull about power pikes surge when powering up such lights...
If you're misting inside the enclosure, I would strongly advise you place the sensors inside and run a wire to the other electronics OUTSIDE the enclosure. There are temp and humidity sensors made to operate in a moist environment, but most electronics will not like that environment. Rather than trying to encase it adequately to keep the electronics dry inside (doubtful imho), it is probably easier to just move them outside. You could use velcro or foam tape or something to secure the node to the glass on the back and then have a tiny wire running to your sensors inside.
Good luck. When you get it running, I'm sure many of us would love to see a write up of your project, with pics of course!
As far as the device receiving the sensor's signals, could they be received by something like this Sensor Shield? or is it better to handle the receive of sensor data by the RPi? Or is this more of a preference kind of situation?
I was thinking of using the shield for the heating elements/lighting arduino at minimum, but if its better to have the driving arduino receive the information and then send relevant sensor data to the RPi for the database part...right now I've been thinking of the RPi recieving the sensor data and then talking to the heater/light arduino when changes/adjustments need to be made (the RPi will be the master of the l2C connection between them anyway.)
Well, the temp/humidity will likely be different enough from the room's temp/humidity to matter to the beings inside the vivarium (I actually have run my apartment's thermostat while I was fixing some heating arrangements to keep him whithin a healthy range...wasn't something I want to do long-term.) I may just run a long wire from the sensor to the nano, either using some single pins of cat5e I have lying around (since it would have a plastic sheathe already) or put it in some heat shrinkwrap.
I went looking for electronics coating materials and I'm probably going to grab a couple to see which work best. From what I can tell, as long as I ensure the humidity sensor's input location stays 'clean', it should protect all the rest of the circuitry from the water mist. They'll be physically protected pretty well from direct watering but the floating water droplets that get in the little enclosure...I want to limit the chance of their damage.
I will definitely be providing lots of pictures of the build I'm always big on credit where credit is due.
As to the lights, I finalized my choice and thus had to make some changes in what I'll be ordering as they're 12vdc; 60W for the daylight circuit and 30W for the moonlight circuit. Thus, FET from what my research turned up and I found a board with 4 channels of IRF540-type power FET. The ones I'm going with are 'full spectrum' 80+ CRI (the 95+CRI ones I was eyeballing weren't flexible with lengths shorter than they advertised which would have run me about 1.5x as much as I'm already shelling out for these lights.) If they don't end up meeting the PAR of the plants, there's room for me to put a light in to supplement them. Just have to make sure they are atleast moderately easy on the eyes- full grow-tier lights would make the vivarium strange and really mess up the snake's senses since reptiles take cues off certain wavelengths as well (which was my driving point of getting a medium/high CRI lighting fixture in the first place.) I've also got a local electrician who will handle a chunk of the mains-wiring and hopefully be able to double check that I have everything properly protected against surges/shorts.
I also found a 4 channel phase-control board for the ceramic heaters. Running the numbers to make sure they will work; I'm probably goign to skip the 200W CHE and switch to something like 3 or 4 CHEs of lower wattages so I can do a more even heat. Probably a 150W in a corner with rocks for a basking spot and then two 100W out another 8 and 16 inches out for moderate ambiant heat.
Sanity check, 4 of the SI7021's (such as this SI7021 can be wired and controlled by one nano? Or do I need one nano for each sensor?