Final project

parts and material list and bill

parts model,material cost
CO2sensor MHZ-19 US$21.8
temprature sensor AT-103A US$1.8
heater GEX Autoheater mini US$15
water pump Seeed Studio mini water pump?? US$6.2
Processor board ATmega328p-AU fabacademy inventry
resistor 10K*1 1k*1 0K*2 fabacademy inventry
capacitor 1uf*1 0.1uf*1 fabacademy inventry
SMD button fabacademy inventry
SMD header pin fabacademy inventry
SMD header pin fabacademy inventry
power board juck fabacademy inventry
SSR fabacademy inventry
mosfet*2 fabacademy inventry
tank acrylic dome US$16
stand,pod ABS
cap ABS,EVA sheat
ring ABS,rubber sheat,3M screw
connector ftdi cable
download files

If you interested this project, please visit github projectand please cooperate.


First idea

final project idea


I plan to make a device that can create a small closed ecosystem on the desktop. The earth (Biosphere) is well-balanced ecosystems, In other words, living things can continue to live in a sealed space if the conditions are right. I hope to make a miniature version of the this However, a miniature one is difficult to control because of less buffers. It will be unbalanced by slight change as temperature, illuminance, and so on. I will make a device that keeps the change to a minimum with heater and a light. Accordingly, the device is installed monitoring devices for environmental change inside the miniature. It is mountable and dismountable unit for balanced ecosystem.


I would like to try various types of ecosystem and share ecological recipes that I could keep for a long time with people. Also, depending on sensor data, I would like to model what kind of living things are consumed and how much, and how it circulates in matter in this space. By modeling, I would like to simulate my ecosystem programmatically, and also to design open ecosystems.

why I want to make this

I like growing plants and aquariums. When I grow up living things, I understand that creatures are alive by ecosystems, and interest in ecosystems comes out. So, I have tried making a small ecosystem. We put a wax bearco in the soil and a small shell in the bottle.

But these creatures have lost their balance and have died. It is difficult to imitate a natural ecosystem in a small space, many failure will happen if you leave it to nature. Therefore, I wanted to create devices and mechanisms that would help maintain balance.And I want to make various versions of


Ideally, I want to make the unit itself closed and jointable, I want to eliminate the clinging container, but we do not know what kind of structure to make. Do I attach sensors and lighting to each unit? One in total? Would I like to be selectively attached as a separate part? How can we make a joint with a degree of hermeticity that water will not leak?

I concern about types of required sensors. Is it necessary other than temperature, illuminance, pH, NO 3, CO 2 or O 2? Are there sensors that can be detected at all times?


Schedule by trello and Elegantt


As week 02 assignment

physical parts



I modeling by makeVR and slice by slicer for fusion360.

I wanted to check balance of stand. I use cardboard for first version and laser cut it.


Version1 is not good gesign, so I update design of stand.I wanted to meke it by milling from wood, so I designed simple one.


I like version2, but I changed the pump, in tank to out of tank, so I need to space to include a pump.I changed the design of stand again.

I wanted to make it by milling, but it need much time,40-200 hours!!, so I made it by 3dprint.

Improve points

island(plants pot)

is land pot is a part of bacterrior's nest and plants pod.


In the beginning I made it to be divided into two in the middle.But it was not useful, it was difficult to insert a hydroball and to plant.


So I change design.I made big hole on the top.


The cap include CO2 sensor and phototransistor sensor and LED.I made several times to verify sensor fitness and size.




n order to prevent water leakage, screws are put on the ring with rubber sheet on the inside to apply pressure.


light sensor

version1 cds cell

First I used cds cell because I used it beforehand and it is not SMD.

version2 photo transistor vynal cutter

Nect I use phototransistor.

I use this made in week13.

version3 photo transistor milling

Because version2 is broken, I made phototransistor boad again.It is same as version2, but used milling.

temprature sensor

version1 LM553Z

First I used LM553Z.It succeed.

version2 AT-103

LM553Z is not stable and it slow reaction.So I used new thermistor AT-103

CO2 sensor

CO2sensor. I use MHZ-19.It costs about $20.It can use pwd.I refer this page.My romm around 400pwm.


I use gex auto heater mini.But it too big and it contain thermostat so I disassemble it. I pick thermostat out.

I sealed heater by sericon.I designed mould.


  • LED light (LK-1WH-6).It on/off though Serial monitor.
  • processor

    Brain is Arduino Leonardo

    I dicided to use ATMEGA328p because I need at least 5 IO (and I will version up my biosphere then more io..) .

    I refer Hello.Arduino.328p.

    shematic is here.

    board is here.

    It could not mill, so I use laser, data.

    First, it shorted.

    I fix image resolution higher, then I got good one.

    After soldering

    I use Arduino IDE(1.0.5) and burn bootloader using AVR mark2.And select this board and wrote test sketch.It work.

    output board

    embedded programing

    New Program.It recieve temprature sensor, light sensor and CO2 sensor and it automatically contral heater and LED.


    Documented in week16





    First I made protype using Arduino and other "version.1" parts above.It It clarified the size and wiring problems.So I update some parts.


    Inside of stand is like below.It little messy with wiring.