After a really busy time, I finally have had some time to work on the paludarium once more. This time I have started working on the various backgrounds using epoxy resin.
Preparing to work with epoxy resin isn’t that hard, but you need to sort out what you will be doing and have all tools required at hand: The epoxy resin starts to set within an hour, so once you have mixed up the components you need to be ready to go. This is what I used:
Preparing for the first epoxy resin layers.
It is VERY important that Read more
Sometimes you have to take a chance. I wanted some realistic roots worked into the background (above water). But how to find nice pieces that will not rot too quickly?
Contestants for a wooden background above water
I have been looking at a lot of different types of wood to use in the background on land. The wood should not rot too quickly, so my first thought was to use driftwood, or rather the sinking type used in aquariums all over the world.
But it proved to be very hard to actually find pieces that Read more
Finally I had some time to build pieces of the paludarium again… This time the background above water, the land portion between the aquatic part and the sump… And the waterfall! In this blog post I’ll discuss the technique used in more detail.
The background is made from a large, single piece of styropor foam:
Starting out with just one big block of stryrofoam… And some cutters.
I took several styrofoam cutters to it before it became a little bit in the direction of what I was looking for. I made several Read more
Now that all the water stuff has been built and tested, I emptied the paludarium again. High time to start working on the backgrounds and waterfall.
The Aquatic background
It makes sense to start with the aquatic background, as I bought this background and do not plan on building it myself. As the paludarium will be amazonian, I choose the amazonian version from Akwaline, and after glueing it in it looks like this:
The Akwaline background glued in place.
I decided to align the background to the right (as I look straight into the right side of the paludarium as well. So the right side is glued directly against the Read more
One of the last things to build and test with all the water stuff, was rain. So I added a small installation with sprinklers that get fed directly from the tap water.
Rain Down On Me
The rain installation is controlled electronically (duh!). On the WaterWorks under the paludarium, I have one electromagnetic valve that can be opened to feed the rain installation:
The magnetic valves on the WaterWorks. The one on the left controls the osmosis filter, the center one inputs tap water into the aquatic part, and the rightmost has now been connected with a thin black tube to allow for rainfall.
The valve on the right has now been connected as well with a thin black tube. This tube is fed upwards, and Read more
Today I filled the paludarium fully. Now the water levels are exactly as projected, and overflow neatly into the sewer if there is any surplus.
Fully filled, the paludarium weighs around 370 kilos right now. And I still need the Canopy on there, sand inside… But the cabinet is holding up perfectly. Nothing bending through, nothing giving way.
If the tap water or the reverse osmosis unit is turned on, it fills the aquatic part. The aquatic part overflows in the dirty-water part in the rear. If that overflows, it is dumped straight into the sewer:
Detail of the sewer pipe in the paludarium. Any access water will flow straight into the sewer. Note how the water is exactly leveled to the edge of the drain.
The inside of the paludarium is a bit of a construction site right now. It looks like this:
Hoses ‘n stuff
Water in the paludarium fully filled. The aquatic part left is about to overflow to the dirty-water part (right) and in turn that water is drained to the sewer.
There are a lot of hoses inside the paludarium Read more
Today it was finally time… All the puzzle pieces for the WaterWorks could be put together! After testing the WaterWorks for leaks, it was time to mount the board under the paludarium, hook things up and test… For the very first time actual water inside the paludarium!
Mounting the WaterWorks
The waterworks were build on a separate board, outside of the paludariums cabinet. All parts that need to be under the paludarium that handle water are mounted here. The WaterWorks look like this:
The Paludarium WaterWorks. This board is mounted under the paludarium and it handles the water household.
Today I mounted this board in the cabinet under the Read more
I am so happy with my Raspberry Pi now able to obtain real-time measurements from the La Selva biological station. As much as this station measures, it does not measure water temperature. Time for some geeking out!
What I DO have
So the measurements I do get from the biological station are basically all the ingredients I need to synthesize the water temperature. Especially these values will determine the temperature:
- Light Intensity;
- Air Temperature;
- Previous Water Temperature.
I want to use some kind of calculation to create a synthetic water temperature. I’m assuming sunlight will heat the water. The water temperature will somewhat follow the air temperature. Finally rain will seriously cool down water.
Making up a formula to synthesize water temperature
Forming a formula that synthesizes water temperature is kind of hard to do. There are so many variables. In the wild, water will come flowing in from somewhere else. Deep water will flow slowly, and hardly heat up under sunlight. A small pool of 10cm of water will heat up extensively, unless it streams fast.
It is almost impossible to work with all these variables. So I figured to just build a simulation formula, and see how the water temperature will develop as I run through the days. I started out with a formula like this:
WaterTemp = WaterTemp + (Light/settings.get(“synth.lightFactor”))
WaterTemp = WaterTemp + (AirTemp-WaterTemp) / settings.get(“synth.AirTempFactor”)
RainDiff = Rain * ( WaterTemp – settings.get(“synth.rainTemp”) )
if (RainDiff < 0): RainDiff = 0
WaterTemp = WaterTemp - ( RainDiff / settings.get("synth.rainFactor") )
The first line will increase the water temperature from the last sample with (Light/factor). This is the heating of the water by the influence of sunlight.
The second line first calculates the difference between air and water temperature. The further apart, the bigger the effect will be. After dividing by a factor, I add this difference to the water temperature (this cal either heat or cool down the water)
The third line first calculates the difference in temperature between the water and the rain. Then I multiply this number by the number of millimeters of rain (more rain = more cooling). In case the rain is warmer than the water (should never occur), I do nothing.
Finally I subtract the calculated value from the water temperature divided by another factor. I use these factors to tweak and tune the simulation.
I still have to look at the effect in a longer run, maybe import a few weeks of simulated data into excel and graph it out. So far it seems to behave pretty well… Simulated temperatures normally run from 24 degrees centigrade (early morning) up to 27.5 degrees centigrade in the late afternoon (4PM). Rain cools it down 1-2 degrees. When looking at heavy rainfall (like September 11th 2013 where there was over 70mm of rainfall in 1,5 hours), the simulation delivered a water temperature of 21.4 degrees centigrade. Not bad at all!
I finally have all the stuff I need for the construction of all of the plumbing around the paludarium. So next was to decide where to place what. And that proves to be quite hard; I have less space than I initially anticipated…
How to place plumbing inside a cabinet
The first question was: How do I place all of the required plumbing in a cabinet while I’ll still be able to work on it properly without having to hang inside the cabinet all the time? The answer was to build everything onto a piece of multiplex and then placing the entire multiplex board inside the cabinet (and then connect up all of the hoses).
I ended up with something like this:
The wooden board where most of the plumbing will go.
At the top left tap water will be connected via the hose laying on top. This hose will connect Read more
In my previous post I managed to program the chips in the Canopy. Now I can adjust the code inside the Canopy where needed. Next thing to get working is to allow the Raspberry Pi to talk to the chips inside the Canopy.
Raspberry Pi, Atmel AVR and serial communications
Luckily the Raspberry Pi has a serial port, because the AVR controllers I used have one too, and they use this serial port to get commands from whoever is controlling the bus… Which should be the Raspberry Pi.
Problem is that the Raspberry Pi does not have a true RS232 serial port: the signals are there (on the GPIO headers), but they have 0-3.3V levels Read more