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Smart Citizen Kit

A note about versions

The SCK 2.0 was the development version for the now commercially available SCK 2.1 sponsored thanks to the iSCAPE project under European Community’s H2020 Programme under Grant Agreement No. 689954

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πŸš€ Installation:

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✨ Something big?:

What is it?

The Smart Citizen Kit is the core of what we call the Smart Citizen System: a complete set of modular hardware components aiming to provide tools for environmental monitoring, ranging from citizen science and educational activities to more advanced scientific research.

The system is designed in a extendable way, with a central data logger (the Data Board) with network connectivity to which the different components are branched. The system is based on the principle of reproducibility, also integrating non-hardware components such as a dedicated Storage platform and a Sensor analysis framework.

On top of that, the system is meant to serve as a base solution for more complex settings, not only related with air quality monitoring. For that purpose, in addition to the Urban Board, the system also provides off-the-shelf support for a wide variety of third party sensors, using the expansion bus as a common port. One example is what we call the Smart Citizen Station: a full solution for low cost air pollution monitoring.

The sensors

Have a look a the supported sensors in the Firmware!

πŸ‘‚ Measurements

All the Smart Citizen Kit new sensors generation measure at least air temperature, relative humidity, noise level, ambient light, barometric pressure and particulate matter (PM).

SCK 2.1

Here is the table summarising the sensors:

Measurement Units Sensors
Air temperature ΒΊC Sensirion SHT-31
Relative Humidity % REL Sensirion SHT-31
Noise level dBA Invensense ICS-434342
Ambient light Lux Rohm BH1721FVC
Barometric pressure Pa NXP MPL3115A26
Equivalent Carbon Dioxide ppm AMS CCS811
Volatile Organic Compounds ppb AMS CCS811
Particulate Matter PM 1 / 2.5 / 10 Β΅g/m3 Planttower PMS 5003

Sensor performance

Make sure you visit the sensor performance page for further information about the sensors.

πŸ““ Installation instructions

The sensor comes mounted and almost ready to be used:

The first step is to connect the battery. The kit will light in red (configuration mode) and we will be able to configure it by following the instructions at

After the configuration process, data will be available on the SmartCitizen platform. You can explore the data there or download it using the CSV Download option (guide here)

πŸ”‹ Power management

Battery duration

The SCK comes with a 2000mAh LiPo battery. The battery is meant to be a complete power option for short-term measurements and a backup solution when the kit it is used for long periods. For long exposures, we recommend to permanently connect the USB to kit. The battery duration is dependent on which sensors are enabled or disabled:

  • All sensors publishing over Wi-Fi: 12 hrs.
  • All sensors publishing on SD card: 13 hrs.
  • Without air quality sensors over Wi-Fi: 10 days
  • Without air quality sensors on SD card: 25 days

You will note that the kit turns itself off while operating on battery. Actually, this is what we call sleep-mode, an operation mode implemented to reduce consumption while on battery operation.

Battery calculator

You can use the battery calculator to estimate how much your battery would last

SCK Battery Calculator

What's the SCK's Shell?

Learn how to use the powerful SCK Shell. Check the guide.

Battery charging

The SCK has a micro USB port and can be charged like any Smartphone or Tablet using a dedicated adapter or a computer USB port.

We recommend using a tablet power adaptor, instead of a computer USB port, for quicker charging. Autonomy can be extended by using a Power Bank, or a 5V PV Panel.

Power Supply

The SCK needs 5V input via the micro USB connector. A normal 5V power charger can be used, although for outdoor developments we recommend using a waterproof power supply. Find more info in the power supply section.

User feedback

The LED serves as an indication of the battery status. If the LED is flashing orange it indicates that the battery must be charged. The battery takes about 4 hours to fully charge. When the battery is fully charged, the LED will change from orange to green .

Remember that in addition to these colors you will have the state color of the kit: configuration, network and sd.

More details

Find more details under the data board section

🚩 User interfaces

The data board features a set of user interfaces which provide feedback to the user, as well as two buttons with different functionalities. The main RGB LED provides general feedback of the data board status. Additionally, two buttons are provided for user action. A hardware reset button, which forces a power cut to the board, and a power button, used to change the device's mode, turn on and off the device, and to perform a factory reset. You can see both buttons below:

The button

The main button interaction is detailed below:

Function Button action
ON Push the button
OFF Push the button for 5 seconds
CHANGE MODE Push the button multiple times to choose: Setup Wi-Fi Pink
FACTORY RESET Push the button 15 seconds for a full reset

An example is shown below:


Have a look at the troubleshoothing section to check how you can use the buttons in case of problems with your SCK!

Operation modes

Setup mode

In this mode, the Kit is ready to be configured in network mode or SD card in

LED color Kit status
πŸ‘ Ready to be setup
πŸ”‹ Ready to be setup but battery is low, charge the Kit
πŸ”‹ Ready to be setup, battery charging
πŸ”‹ Ready to be setup, battery charged

Wi-Fi mode

This is the standard mode for a network that requires a Wi-Fi connection. In this way, the device will publish the data every minute on the platform. If there is an inserted micro SD card, the data will be stored in duplicate.

LED color Kit status
πŸ‘ Collecting data online
⚠️ Error while collecting data
πŸ”‹ Collecting data online but battery is low, charge the Kit
πŸ”‹ Collecting data online, battery charging
πŸ”‹ Collecting data online, battery charged


βœ… The kit supports Wi-Fi WEP, WPA/WPA2 and open networks that are common networks in domestic environments and small businesses.

❎ But, it does not support WPA/WPA2 Enterprise networks such as EDUROAM or networks with captive portals such as those found in Airports and Hotels

SD card mode (offline)

If we do not have an internet connection we can use the SD mode. In this case the device will record the data on the micro SD card. Later we can read the card using a card reader. The data can be visually spaced in a spreadsheet but also published on the platform using the UPLOAD CSV option.

LED color Kit status
πŸ‘ Collecting data offline
⚠️ Error while collecting data
πŸ”‹ Collecting data offline but battery is low, charge the Kit
πŸ”‹ Collecting data offline, battery charging
πŸ”‹ Collecting data offline, battery charged


Check the guide on how to upload the sd card data here

Weird files?

The files in the sdcard have the following naming: YYYY-MM-DD.CSV, however, you will find in the some extra files (.01, .02...) These are data files that the sensor creates once there is a reset and, to avoid corruption, it creates a new file in the sd-card, by changing the file-extension.

A reset takes place every night at 3-4am with the purpose to avoid data loss because a problem. The SCK then stores the data in a file with a sequential name, and does so by changing the filename to YYYY-MM-DD.01, .02… etc depending on the amount of resets it sees during that day. You can see the data and work with it by changing the name from YYYY-MM-DD.01 to YYYY-MM-DD_01.CSV. Check the guide on how to organise your data to automatise this.

Especial status

LED color Kit status
⏳ Busy, please wait!
πŸ”§ Software update going on!

Software Updates

Sofware updates are release frequently in the Firmware repository. These updates will need to be applied periodically to the two main components of the SCK: the SAMD21 (main processor) and the ESP8266 (Wi-Fi module). Check the instructions under the Update the Firmware section for more information.

Smart Citizen Kits being tested at Fab Lab Barcelona

Test plan

You can find the Test plan, in case you are producing the SCK here.