Search the Community
Showing results for tags 'raspberry pi'.
Hi everyone, Now that my Terrarium is up and running I thought I should introduce it properly and show you the steps of the build along the way, which may help to inspire others to create similar projects. I used to have a small terrarium, which consisted of an old 45x30x25cm fish tank, lit by a 6400K 45W spiral compact fluorescent. It worked ok and the light certainly was powerful enough just to grow plants but it had problems with keeping the heat under control, keeping the water conditions stable and inevitably; I simply ran out of space! Last year I found a larger, second-hand fish tank and soon put together the idea of an LED build for a more hi-tech and efficient terrarium to allow my plants to really thrive. Here, finally is the result of my setup... It's a 75cm x 32cm x 39cm grow space that's warm and humid - in order for me to grow tropical species year round. I went with 55x 3W star LEDs, comprising 28x Cool white and 27x Warm white in equal spacing. The LEDs came from Michael Houlder at FutureEden (via his ebay shop). He's a great guy and helped me with my initial questions into LED wiring and electronics. I needed a heatsink to mount the LEDs to and also to form the entire hood of my terrarium. After a lot of searching around, I opted for a custom-made, black-annodised aluminium heatsink from Birmingham Aluminium (http://www.bal-group.com/home). They were very helpful and communicative to discuss my needs and clarified the thermal properties of the heatsink would successfully handle the proposed 55x 3W LED heat load. This was the single most expensive item in the entire build, but was critical to ensure I had a lasting terrarium with safe temperatures. The heatsink sits perfectly flush with the top, left and right sides of the tank, but has a very small 1cm air gap at the back - providing a small but useful exchange of fresh air as well as some space for any wiring to go into, or out of, the tank. Here's the heatsink, with a pair of T-bar handles installed so that I can lift the hood off (relatively) easily... The spacing for the LEDs was carefully checked using a handy PAR calculator via an excel spreadsheet. This had been set up for aquarium enthusiasts to calculate that the proposed spread of light would achieve a desired PAR level. If I remember correctly, I shot for a PAR around 2000, which is close to full sunlight (aim high, right!) LED's glued in place with thermal adhesive... With the spacing sorted, I then planned the wiring, making sure it was as neat and efficient as possible but still allowing for an even distribution of cool and warm white. The two 'sets' of LEDs are run on different drivers so I have the option of having the Warm and/or Cool white banks on at any one time. This also allows for future adjustment to light schedules and time overlaps. The wire used is silicon-sheathed which is heat proof and highly flexible. Planning the wiring.. Main wiring paths soldered in place... First test of the drivers and warm white LEDs... Wow, extremely bright and painful to look at. A stopped-down photograph shows the individual LEDs better than our blinded eyes can see.. Here is the hood in place with tested lights on - remember this is still only the warm white set (half the total)... Time to wire and test the Cool white set... All LEDs on together (camera stopped down to be able to see properly)... (The yellow wire is an earth - connected all the way to the plug earth and will be attached to the aluminium hood for safety in case of any wiring faults that may occur) Full brightness over the tank... My original ideal PAR calculations, incorporated the use of 30° lenses in order to direct the LED light efficiently downwards onto the plants. At this stage I hadn't installed them yet and it is quite clear that a lot of light is being wasted in all directions. The following composite photo shows the light spill of the LEDs by highlighting what little effect the main room light had when on or off! If you look at the carpet, you can see the bands of shadowing as the different rows of LEDs catch the edge of the sideboard... I glued each individual lens on as the holders they come with did not offer a good enough fit, especially with the soldered wires in place. I discovered that stacks of 2p coins formed the perfect sized weight whilst the epoxy was setting. (I opted for epoxy as the chemicals in superglue can apparently fog up the clear lenses!)... With all the lenses in place, the light spread is much more defined inside the tank with very little over spill outside.. Out of curiosity, I placed my phone into the bottom of the tank (35cm from the lights) and took a light level reading using it's inbuilt sensor... 38,000 lux; equivalent to sunlight! This was by no means a scientifically precise reading, but it was an excellent sign for me. Before filling up with water and introducing plants, I was concerned that all of my careful wiring and expenditure was at risk of corrosion from the high humidity conditions. Therefore I decided to fabricate a 'light shield' from 3mm perspex sheet. I checked the specifications and light transmittance is 92% - I could afford to lose 8% light in order to protect my hard work. The shield is simply a box-like structure of epoxy jointed perspex, mounted to the aluminium with clear silicone sealant. I left the threaded rods long, that come from the handles above and allowed them to pass through the perspex by drilling holes. This gives me options to attach anything to the rods in future, and they do not interfere with the light spread... Now the terrarium was safe and ready to start thinking about plants. I placed some eggcrate in the bottom, in order to allow me to have a 'reserve' of water in the bottom of the tank for stability, humidity and for the ultrasonic fogger to use... Here is the fogger in place. The eggcrate is elevated by a series of upturned 8cm net pots, which are rigid enough to hold whilst being fairly open to allow water to pass freely through... Following Tom Bennet's tutorials, I was able to introduce a Raspberry Pi system into the terrarium, constantly monitoring temp and humidity and allow for the use of autonomous mains sockets. Here is the 'powerhouse' (the raspberry pi)... It reads temperature and humidity via an AM2302 sensor, connected via CAT5 ethernet cable (placed well out of the way of the splashing ultrasonic fogger!!)... You can view live readings from my terrarium here... https://thingspeak.com/channels/149828 The fogger is connected to an Energenie RF controlled mains socket, which is triggered by the Raspberry pi every hour at one minute past, for a duration of six minutes (day and night). This gives a boost to humidity, yet is unobtrusive and dramatically extends the life of the disc in the ultrasonic fogger as it is effectively only operational for 144 minutes in a 24 hour period. The constant RH monitoring means that the raspberry Pi can be set to trigger the fogger based on a desired humidity range, but I don't think this is necessary for me at the moment. The last object I added to the system was a simple aquarium algae magnet, which sits permanently in the top left corner of the front glass. This allows me to wipe the front pane clear of any condensation if/when I want to be able to see clearly inside... That's the whole setup so far. It's been challenging at times but very fun and extremely rewarding to learn along the way. I am more than happy with the results and the effect already on the plants living inside. My next post will show the plants inside.
Hey there, I thought it was time for me to introduce in this thread my new terrarium. It will be more 'techy' than 'planty', so if you are expecting mainly pictures of plants here, well, you'll be pretty disappointed. I started over 6 months ago with this new project, as I had to stop growing carnivorous plants and put away my former terrarium. I hope it will meet the same success as its elder brother. The previous one was already running with a RPi, but its use wasn't maxed out. Here we go, the result as it was a few weeks ago: Basically, it's a small terrarium (65x55x65) dedicated to grow highland carnivorous plants, but also, to answer my needs as a grower: autonomous, tailored set up with remote monitoring. Handy, transportable by one person, and good-looking (enough). Almost bearable in a living room, i.e, not giving away too quickly a vibe of 'eccentricity'. But behind the scene, it's a different kettle of fish. I bought the glass panes, and started to drill them. The holes will be used for aquarium tubing: Practising: Then starting with actual panes: Watering the area of interest: Then: The silicone used to joint the terrarium together: A bit messy: Top pane set up. I stuck the first rail for sliding panes. Wait of 24h. Then final jointing and installation of the through-tank connectors. 48h wait, and leak test : I built a small tank made of 2 cm styrofoam to contribute to insulate the cooled water from the outside of the terrarium. The aim was to prevent cold losses and reduce outside condensation on the window: Second profile rail drying: As a side note, the bottom profile rail is smaller than the top one, allowing easy removal of the sliding panes : Slicing off a gutter, so to make support for gratings : To water the plant wall, I set up a pierce hose on top of it: Stuck hose: Cheeky bubble: Same goes with the tree fern panels: I made a tank for the fogging system, as well as two shelves (one for the tank, one for the watercooling radiator): The shelves: Final test: Now, about the lighting system. In short, I wanted LEDs, as they have more opportunities for playing around. They can be dimmed and can have precise wavelengths. So it's possible to roughly mimic sunrise/sunset. I used several small ones instead of few big ones because I wanted passive cooling (silent installation), and not being forced to have fans running on top of big LEDs to have them cooled down. I bought MK-R LEDs and no-name ones (blue: 440-445, 430-435nm and red: 660nm), all powered around 4W. The MK-R as I received them: The first step is to mount the MK-R on their individual PCB: I spread solder paste on the PCB: I did reflow soldering, by making solder paste melt between the PCB and the LED. Information about the specifications on how to carry out this process can be found on the MK-R datasheet: Useful thermometer (there wasn't any LED on the pan at the time I took this picture): Then, I drilled and mounted some heatsinks together: I added some tin to make the connecting easy: Thermal paste and other tools: The beginning: (there was actually a mistake in this wiring at the time of the picture) Finally: White: Yellow: Red: Blue: Warm effect (morning): Winter-is-coming effect: A bit of an overkill, but in case, some fans to help the heatsinks dissipate the heat: How the lighting system is fixed. Inspired from aquarium hobby: Funny trick - how to adjust the height of the lighting system: The fusebox, when I was still tinkering with the RPi: The cooling system (below 13°C at night and no higher than 25°C during the day): The cooling unit: The connectors: The watercooling radiator: The heating system is based on a heating pad and a fan (that I also use for the fogging system, and all day long to promote air circulation): The fogging system, with classic mist makers: The watering system is composed of 4 nozzles: And a pump: And for the geeky part, the Raspberry Pi to rule them all. This is the micro-controller (small computer) which manages all the devices related to the terrarium. Good news, you can do almost everything you want. Bad news, the RPi won't program itself: I connected several sensors and other hardware resources to it. To have something neat, I designed a printed circuit board (PCB). Yep, the schematic is quite messy: Rendering this after milling (a friend of mine milled it for me): I soaked it into liquid tin: Then, components' supports: Tropicoat coating: In the end, more or less: A webcam on top of the terrarium: Which gives this kind of snapshot (I consider doing time-lapse, as soon as I don't have plastic bags on top of some plants. I removed them for the sake of the pictures): How to command the devices ? Using relays. I had some that I very recently replaced with wireless (radio/433 Mhz) ones. The emitter: The relay: A receiver (to copy radio signals, or for instance, coupled with a remote controller to switch off the terrarium): Family picture: And not-so-useful remote controllers, as everything is managed by the RPi. They bypass the RPi (as they send the same signals as the RPi do), so, I can turn on/off a device without having to use the RPi, and without tampering with the rules I set up. I just have to ensure that I put the device back in its original state after I'm done operating it. About coding, I had a first version which was working but far from being optimised. The crucial upgrade was made possible thanks to Clément Lefranc, who gave me his entire code. He is the one who takes the credit. Thanks to his gesture, I could start from a working base that I adapted to my own needs. As you might be assuming, I have developed a website to better introduce the terrarium. Almost finished with it, just left with a few things to correct. It will be more convenient to look up for any information related to the terrarium, as I'm afraid there are too many pictures on this topic. But in case of major update, I'll make sure to put the info into this topic as well, so that the gist is always presented here. That was all for the initial investment. Then, what is interesting is to watch how the plants will react to all this attention. Especially in the long run, as, when it comes to growing, that is the only thing which matters in my opinion. And the more it is complex, the more it's likely to break down somewhere. But I'll keep you updated. At least, the start is successfully completed: believe me, it could have not been so. I hope it might give ideas to some of you. Vince P.S: I still can't get my hand on the 'preview button'. Has it totally disappeared? Is there any way to have it back?