The aim of our project is proving that microbes exist at high altitudes - more specifically 1-2 km into our troposphere. We want to build a satellite that is able to collect air samples from high altitudes. These samples would be then filtered in order to get rid of any contaminants leaving only the desired microbes in between the filters. Additionally, the results of our experiment, apart from promoting the idea that life is possible on other planets than Earth, could help understand better the life cycle of bacteria here on Earth. Painting a big picture of growth and needs of simple microbiological organisms could help us understand how to fight the harmful ones and how to effectively make use of neutral or beneficial organisms.
One of our main objectives is to make project an open-source - this means we want all of our work to be available online to potentially benefit similar projects in the future. Moreover, it makes following our project easier than ever. Below you will be able to view and download all of our projects. This is the purpose of our GitHub page.
- Introduction
- CanSat description
- Mission Overview
- Hardware Design
- Electrical Design
- How to code the Air Thief
- Ground support equipment
- License
The Air Thief team consists of 5 members from Akademeia High School. We formed a team as we believed the CanSat competition is a one-time experience that will allow us to polish our skills as well as gain newfound skills from the process. We came up with the idea of creating the Air Thief - a satellite that would be able to collect air from an altitude of 2km, which can be later sampled for microbes. Throughout the competition, we have brainstormed how we will achieve this, as well as have gained partners such as Adamed, Cloudferro, JLCPCB, CubicInch and Thorium Space Technology, who see great potential in our work and are willing to support us with their resources.
The medium through which we want to accomplish our mission is the CanSat competition - a competition organized by the European Space Agency with the goal of building a real satellite within the volume of a soft drink can. This competition takes place every year and is held to very high standards as initially, over 80 teams per country participate in the challenge.
There are many opportunities for patenting ideas, meaning this is definitely an area for business. As an example, the recent mission exploring life on Venus, which would require a satellite that would be able to collect microorganisms from the atmosphere.
The project consists of a primary and a secondary mission. The primary mission consists of measuring the temperature and pressure throughout the whole flight of the satellite. The CanSat will therefore include an additional sensor specified to take those measurements. The data obtained should be sent to the ground station every second to allow the team to analyze the information given and plot graphs that should facilitate the execution and organization of the secondary mission. It is important to notice that measuring both temperature and pressure, will allow us to identify the position of our satellite, as these two factors can be modelled to provide the height at which the system is placed at some point in the given time.
The secondary mission is designed to investigate microorganisms, at a designated height above sea level. To pursue this experiment, the satellite will be equipped with four filters, enclosed in two sterile chambers, allowing the separation of the desired sample from any other contaminants. The air will be pushed through the sterile chamber described above with the use of a pump to increase the possibility of collecting the samples only at the desired height. The aim of the secondary mission is also to measure the humidity at a certain height above sea level. This will be done using the same sensor as the one used in the primary mission. It is crucial to know the level of humidity to adjust for the filter air flow capacity.
The main core of the satellite is designed using Fusion 360. We decided to collaborate with Cubic Inch to use their expertise and technologically advanced tools to print our core of the satellite. The company uses the Multi Jet Fusion technology provided by HP. The materials used by such a printer is the Polyamide PA12 which is a strong and durable material, therefore our satellite and its components will be protected when it falls to the ground after the fall.
The following files are uploaded in the 3D folder:
The electronics consist of two main systems, the 5V and the 6V. The power is taken from 3 lithium ion(3.7V 750mAh) batteries rigid in series to provide 12.6V when charged and 750mAh of capacity. There are 2 main converters, a 5V and a 6V. The 6V converter powers the air pump that pulls the air through the filters. The 5V converter powers the microcontroller, the buzzer, the led and the GPS, the sensor is powered through the microcontroller with an 3.3 V. The wiring is basic, the power needs to be wired to all components respectively. The wiring between the feather wing board and the components is a bit more complicated.
The core of our secondary mission will be the NW Air Pump which will be used to push air from a high altitude through a series of filters. To power the NW Air Pump with 6V and 400 mA current a step-down converter (D24V10F6) will be used to change the battery voltage of 11.1 V, also a second step down converter (D24V22F5) will be used to power the main controller with 5V and 700 mA.
To power the CanSat, three Li-Ion 750 mAh batteries are used and the voltage is stepped down for the other components. To turn on the pump, a relay is used for safety in case of a short in the motor the motherboard will not be damaged. A GPS module is used to determine the coordinates of the CanSat, and these will be sent to the ground station. To help with finding the CanSat after landing an 80dB buzzer is used, if the CanSat is hard to find visibly, it can be also found using sound.
The primary onboard computing unit for our CanSat is an Adafruit M0 that supports Arduino. It is going to run all the programs necessary for the functioning of the CanSat and all onboard equipment and experiments. The flight plan for individual atmospheric Microbiome soundings can be fine-tuned, which is helpful. The data will be recorded to a MicroSD card, which will probably have such high storage capacity that it will be virtually infinite for our purposes (16 GB, around 30 zloty). The program has 3 main modes, controlled based on the current altitude measured by the temperature-pressure sensor. This is going to ensure the correct data is always transmitted and minimum power is consumed. If the AdaFruit sensor detects an anomalous result, the mode will have a 3000 millis switch cooldown so that it is not turned on preemptively. Our reasoning is that since the primary mission is so important, relying on it for data is quite sensible.
When the satellite is waiting on the launchpad and when it has landed post-experiment are similar flight conditions and require a similar approach. Thus, Standby mode is active when the CanSat elevation reported via the AdaFruit array is less than 100 meters AGL. During this mode, the CanSat is only running the first experiment, sampling the ambient temperature and pressure, and computing the altitude at regular 10 second intervals, ready to switch into an active state when the altitude goes beyond 100 meters. The buzzer is on while in this mode only if the Sampling flag has been set, meaning that the vessel has entered sampling altitude at least once. The buzzer pulses at an optimal frequency that can be heard from a large distance (2700 Hz)
When the satellite is in flight, above 100 meters AGL, it constantly calculates its position and AGL via the GPS and AdaFruit sensors. [This means sampling occurs at 500 millis intervals.] These parameters are then transmitted to the ground station, so that a flight profile can be determined. If the altitude were to increase or decrease, Sampling or Standby modes would be engaged, respectively.
The pump powering the secondary experiment is enabled. It runs constantly until either the total runtime requirement is satisfied (so as not to overshoot) or until the CanSat goes below 80% of the mission altitude (2 km for a 2.5 km mission, for instance, this is configured pre-launch). That way the sample is collected from the correct experimental band that was being sampled (for instance one that has a height of 0.5 km). During Sampling, the Active activities are also conducted. If the sampling altitude is passed and the CanSat begins heading down again, Active, and then finally Standby modes are engaged. When Sampling mode is entered for the first time [since last boot], a system-wide flag is set that is later used to determine whether the Buzzer should be turned on while in Standby. The data recorded via the MicroSD card, and the outgoing transmissions sent out via radio will have a specific format that will minimize their size, enabling higher efficiency. [This means that the timestamps used for instance are going to be epoch time that can be later converted into human-readable time values, not in situ in the POCU but in the gstat after receiving it.] The ground station program will be coded in JS for the frontend, and in Python3 for the backend.
Laptop running the backend and frontend for the communication with the satellite. The frontend handles the display of data on screen and the issuing of commands to the CanSat, and the backend communicates directly and writes to files, etc. The frontend is written in JS. The backend works in Python. One of our programmers proposed an additional backend (a middle end if You will) that will kick in if some gstat OS crash occurs, to prevent any local data loss. This is just called a glorified log file, but still.
A YAGI omnidirectional antenna that will send and receive data from the CanSat. It is connected to the Laptop. A power supply for the laptop and the antenna. This is a backup, as there is most likely mains power in situ at the launch site. A port-a-nanolab with materials applicable for the final selected procedure if needed.
- Lab safety equipment (coat, glasses, gloves)
- Flow cytometer in Adamed’s Laboratory
- Cytometry prep kit
- Professional glove box
- Self-adhesive foil
- Isorapid spray or ethanol
- Set of tools to open the chambers
- Tip or inoculating loop or cotton swabs
- UVC lamp (inside or outside)
- Sterile swabs
- Sterile agar plates
- Transportation box
- Plastic zipper bags Alternative support equipment that we considered to conduct the analysis of the microbes (provided by Adamed) that might be used as a backup form of conducting the analysis [updated]:
- UV-C filter
- Standard amateur-grade light microscope [has role of backup & validation device, capable of detecting microbes within light diffraction limit, that means it is easily capable of detecting bacteria]
- Immersion oil for oil immersion of microscope objective lens (sic!)
- PCR Thermocycler with master mix, primers, etc. for Virus DNA amplification
- Electrophoresis equipment for DNA electrophoresis post-PCR
- SYBR Green Dye dispenser, plus other dyes and chemicals needed for the procedure.
- Viral genome extraction equipment
- UV-Vis spectrophotometer for virus quantification
- Lab-grade Fluorescent Microscope
- Accurate scale and other basic measurement equipment
- Sars-CoV-2 Quick-Antibody detection kit for testing teammates (pandemic control related if needed).
- Microorganisms instant detection kit (obsolete).
Our work is licensed under the ACADEMIC PUBLIC LICENSE that allows noncommercial use specifically restricted to an education environment. To use this software for commercial purposes a commercial use license must be purchased. This means You can safely launch a CanSat with this software and can modify it to work for Your specific mission, but cannot sell the software or use it to make money in other ways.