Problem

In cities like Wrocław (Poland), smog and air pollution pose challenges not only for residents but also for local governments, social organizations, and educational institutions. A local, easy-to-implement, and precise measurement solution was needed to monitor air quality in real-time. Although we developed this solution for ourselves, we present it as an example of a process that could be implemented.

Idea

To create a compact, affordable, and easy-to-deploy device that:

🔹Measures key fractions of suspended particulates (PM1, PM2.5, PM10).​

🔹Allows data visualization online and in a mobile application.​

🔹Can be mounted in various locations—on streetlights, trees, buildings.

What we did

We developed a dedicated air quality sensor based on IoT technology.

The key challenges included:

• Designing a small and durable device.​

• Selecting sensors to detect PM1, PM2.5, and PM10.​

• Ensuring reliable data flow to the application.​

• Creating a simple interface understandable for end-users.

Using MQTT technology, data is transmitted in real-time to a server, where it is processed, stored, and visualized. Users can monitor pollution levels via a mobile application or a website. The device can operate independently or as part of a larger network of sensors, e.g., within Smart City projects.

Capabilities of the air quality measurement device

✅ Measurement of PM1, PM2.5, and PM10 Particles

Equipped with an optical sensor (e.g., laser-based), the device measures the concentration of solid particles in the air in real-time—with accuracy suitable for urban and educational applications.

✅ Remote Data Access (Cloud Ready)

Data is automatically transmitted via the MQTT protocol to a server, where it is stored in Elastic. It can be accessed through:

• A mobile application (e.g., React Native).​

• A web panel (e.g., built with React featuring charts and alerts).​

• Integrated APIs (for use in external systems).

✅ Mobility and Independence from Electrical Grid

The device can be powered by:​

• A solar panel.​

• A high-capacity power bank.

• A standard power adapter (if available).​ Designed for mounting on trees, poles, fences—without the need for special infrastructure.

✅ Scalability and Readiness for Mass Deployments

The architecture of the device and system is optimized for deployment in:​

• Entire city districts.​

• School networks.

• Municipalities.​

• Social campaigns.​ With the ability to aggregate data and report at a central level.

✅ Integration with Educational and Environmental Activities

Data can be:​

• Used in school programs (e.g., lessons on ecology, physics, biology).​

• Publicly displayed on screens/monitors in schools or offices.​

• Combined with social campaigns (e.g., encouraging the use of public transport on high-smog days).​

• Shared with local communities (via online maps or push alerts).

Implementation process overview

Phase 1 – Device prototyping

Development of PCB, casing, and measurement algorithm. Testing using 3D printing and microcontroller programming in C++.

Phase 2 – Data transmission and backend

Utilization of MQTT for data transmission to the server. Data is aggregated and stored in Elastic.

Phase 3 – User interface

Frontend based on React. Enables data visualization in the browser and mobile application.

Phase 4 – Pilot and optimization

Devices were tested in an urban environment (e.g., on poles, trees), and the entire architecture was optimized for energy efficiency and continuous operation.

Potential deployment areas

🔹 IoT Hardware: Custom measurement device with dedicated PCB.​

🔹Backend Software: Java, MQTT, Elastic.​Hackster.io+9Circuit Digest+9Tindie+9

🔹Frontend: React application + mobile version.​

🔹Communication: MQTT data transmission + real-time visualization.​

🔹Data Analysis: Integration with Elastic and dashboards.

Technologies

⚙️ Java (backend),

⚙️C++ (microcontrollers).​

⚙️React (frontend).​

⚙️MQTT (data transmission protocol).​

⚙️Elastic (database and analytics).​

⚙️3D printing, PCB design, consumer device prototyping.

Team size

🧑‍💻 4 people (IoT engineer, backend developer, frontend developer, hardware prototyper)

Duration

🕒 12 months—from concept to MVP production and environmental testing.

Applicable in situations such as:

• Education and schools – supporting environmental awareness programs and practical science activities

• NGOs and the public sector – enabling data-driven environmental monitoring and advocacy

• Outdoor events – providing real-time air quality insights for safe public gatherings

• Local governments and municipal administrations – for smart infrastructure and community alerts

• Green tech and environmental startups – as a platform for scalable innovation and data integration.