Monitoring Indoor Air Pollutants – The Silent Issue for Smart City IoT using Seeed Wio-E5 and Fusion PCBA

Updates!! This is HUGE! Big congrats to Mircea-Iuliu Micle on winning the BEng Pathway Award at University of Plymouth with his amazing project “AERQ-Indoor Air Quality Monitor”. We’re super happy to have the chance to support his project based on Seeed Wio-E5 module and Fusion PCB Assembly service!

Mircea win the BEng Pathway Award at University of Plymouth

Many people ignore or they don’t know about the dangers lurking silently in our homes that threaten our well-being, things such as mold, lead, smoke, carbon monoxide to name a few, with the indoor air pollution being ranked by the EPA as one of top five environmental risks.

Why is this project relevant?

During the Covid-19 pandemic, most people were forced to spend a lot more time at home and might be unaware of how the air that they breathe might influence their well-being. A polluted room or house can lead to irritation of eyes, headaches and long-term exposures can lead to respiratory diseases or even cancer.

This project is intended to provide an insight into the air quality within a room or house or even office, making use of an IAQ sensor with AI capabilities. This sensor uses a “breath-VOC” mixture to detect exhaled human breath and it measures the concentration of volatile organic compounds, using the BSEC 2.x library to output an IAQ. This could alert the user to let’s say open a window or if the conditions are extreme, look into purchasing an air purifier.

Fig.1 Bosch datasheet for the BME688

Seeed Wio-E5 Module – A Highly Integrated Choice

Previewing 20220421_143142.jpg

This projects uses an STM32WL – Seeed Wio E5- for the brains and a Bosch BME688 to get the IAQ, using the BSEC 2.x library. A version with an integrated antenna and one with an SMA connector. All boards feature a 4-layer custom board.

The final year student Mircea-Iuliu Micle at the University of Plymouth UK, after a long search of integrated packages or MCU + RF trans receivers combos, the Seeed Wio-E5 choice was easy. It provides the Long Range RFIX(SX126X) with the STM32WLE5JC MCU on a single module, providing high performance and low energy consumption in a tiny package. On top of this, all it needs it’s 2 capacitors and an antenna!

With plenty of peripherals and memory available, the module is also capable of running Arm’s Mbed Os ( ), making it a perfect choice for rapid prototyping and IoT.

Fig.2 Range testing

This project features a custom 4-layer PCB, with two antenna options, using a USB cable for power. A decision was made against using a battery to simplify the design and reduce the development time, but a LiSocl2 battery will get this going for a few years!

This version also features a JST-SH connector to connect a battery, using an efficient buck regulator.

Fig.3 PCB Layout

Using Mbed Os and the provided LoRaWan stack, data is parsed to The Things Network which acts as a bridge. In future version, the Long Range credentials will be stored into flash memory.

From there, for this version, data is parsed using MQTT to an Android app made using KivyMD. A version where data is fed into Azure IoT Central has also been tested, but that is more expensive on the long-term. A picture with an Android prototype app taking data from The Things Network:

Fig.4 Android app

Data can also be sent to Azure IoT Central through Azure IoT Hub:

Fig.5 Azure IoT Central

In terms of antenna performance, while a chip antenna is not particularly great, I was able to get around 1 km in an urban environment with lots of cars, building and AC power lines, showing Wio-E5’s impressive performance!

Fig.6 Range testing in an urban environment

Make your project more easier and professional by using Seeed Fusion PCBA service

Mircea said:

“Using Seeed Fusion PCBA service made this project a lot easier. I might not have all the tools needed to assemble and test my boards properly, so it’s great to have the professional manufacturer do it for you.

I call things as i see them, Seeed Fusion’s PCBA service level is first class! They provide personalized service according to the different needs of each customer. Especially, for the Fusion PCBA manufacturing here, you can also enjoy Free DFA review and Free functional testing for one piece, which can avoid reworking and speed up your product landing and time-to-market!

On top of this, their support is great and they’ve answered all my questions promptly! You can’t really go wrong with the Seeed Wio-E5 Module, either if you use it as a trans receiver with AT commands or as a SiP. “

Fig.7 PCBA versions

Take action to bring your Wio-E5 projects to the next level!

To accelerate the development of IoT industry to the next level, Seeed is 100% sponsoring Wio-E5 projects with the Seeed Fusion PCB Assembly Service for all hardware enthusiasts, designers, makers, and engineers around the world!

Good ideas need to be discovered, and good projects deserve to be recognized, realized and widely disseminated! Each person is limited to two PCBA boards 100% completely FREE for one design, including PCB fabrication, the cost of parts, assembly and shipping. The design must include Wio-E5.

If you have an interesting concept for Wio-E5 and are willing to share it with the community, share it with us and we can help you make it a reality with Seeed Fusion’s one-stop-shop capabilities. Get 2 boards fabricated and assembled completely free with Seeed Fusion’s turnkey PCB Assembly service.

Furthermore, choose all your parts from the PCBA Open Parts Libraries (OPL) and reduce the lead time to as little as 7 working days. Meanwhile, if you have mass production requirements, we highly recommend taking advantage of the Seeed Fusion PCB Assembly service and get the Wio-E5 modules for only US$7.90 (28% discount, original price US$10.90).

Get started now!!

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April 2022