Imagine combining the power of an off-grid LoRa mesh with the intelligence of cloud-connected telemetry.
The Seeed Studio Wio Tracker L1 Series Meshtastic Development Kit provides the perfect foundation:
an ultra-low-power nRF52840 microcontroller, integrated LoRa radio, and high-precision Quectel L76K GPS.
This development kit is already a reliable Meshtastic node for communication in remote areas.
We are extending its functionality by integrating telemetry sensors to capture environmental or situational data,
and pairing it with a XIAO ESP32S3 that acts as an MQTT gateway. The result is a hybrid system where field data flows
through the mesh locally while also being accessible globally in real time.This project focuses on transforming the Wio Tracker L1 into a robust, enclosed Meshtastic node that can function as either a sensor node or a gateway
How It Works1. Telemetry Data Capture
The Wio Tracker L1 can interface with a wide variety of sensors. For example:
- BME680 for temperature, humidity, pressure, and indoor air quality (IAQ)
- SCD30 for precise CO₂ measurement in agricultural or industrial environments
- Soil moisture sensors for smart farming applications
- Gas sensors (e.g., CO, VOCs, CH₄) for safety and hazard detection
- Accelerometers or vibration sensors for structural monitoring
The sensor readings are collected at scheduled intervals (e.g., every 60 seconds), formatted into compact payloads,
and handed to the LoRa subsystem for transmission.
2. Mesh Transmission
Once encoded, the telemetry data is broadcast into the Meshtastic mesh. Other Wio Tracker L1 nodes in the area can
receive, relay, and log this data. Because Meshtastic operates as a decentralized mesh, no single point of failure exists.
This ensures robust, resilient communication even in challenging environments where cellular or internet coverage is absent.
3. MQTT Cloud Gateway
A XIAO ESP32S3 serves as the crucial bridge. It connects to the Wio Tracker L1 using UART or BLE. On one side,
it listens to incoming telemetry packets from the mesh. On the other side, it uses Wi-Fi to connect to a configured MQTT broker.
Each incoming message is parsed, tagged (with metadata like device ID, timestamp, or GPS location), and published to MQTT topics.
Example MQTT topics could include:
- telemetry/device123/temperature
- telemetry/device123/soil_moisture
- telemetry/device123/co2
- gps/device123/latitude
- gps/device123/longitude
This structure makes it easy to subscribe selectively to the data streams you need.
4. Global Visibility
Once in MQTT, the data becomes highly versatile. You can build dashboards using Grafana, Node-RED, Home Assistant, or
even mobile apps. Remote teams can monitor environmental conditions, track devices on maps, and set up alert systems.
For example, if CO₂ levels spike in one area, the system can send instant notifications via email, SMS, or Telegram.
PCB OverviewThis PCB is designed as a carrier/expansion board for the Seeed Studio Wio Tracker L1. The board layout shows the Wio Tracker L1 module positioned at the center-right, with supporting connectors and headers placed around it. The enclosure outline suggests it’s intended to fit into a rugged outdoor case, which makes sense for Meshtastic deployments
Key Components and Connections- Wio Tracker L1 (Main Module)The main Meshtastic board, containing the Nordic nRF52840 MCU, LoRa radio, and GPS module (Quectel L76K).This module handles communication, GPS positioning, and LoRa mesh networking.
- Header H1 (Right Side, Connected to Wio Tracker L1)Provides access to GPIO, I²C, UART, power, and ground.This header acts as the bridge between the Wio Tracker L1 and your add-on circuit (in this case, telemetry sensors or a gateway board).
- Header M1 (Top Left)Breaks out multiple pins from the Wio Tracker L1 for expansion.From the labeling (GND, VCC, I²C lines, possibly UART), it looks like this header is meant for external sensors or peripheral modules.
- Sub-board / Module Connector U2 (Bottom Left)This smaller PCB footprint is for an add-on module (looks like a Seeed Studio XIAO footprint).Most likely, this is where your XIAO ESP32S3 plugs in to function as the MQTT gateway.It connects back to the Wio Tracker L1 through routed traces (probably UART for data exchange and shared power lines).
- Power and Ground RoutingMultiple VCC and GND lines are fanned out to both the Wio Tracker L1 and the XIAO footprint, ensuring stable power delivery.This means your design can either run on the Wio Tracker’s battery system or have additional power sources routed in.
- Enclosure Mounting HolesFour mounting holes at the corners indicate the PCB is designed to fit securely inside a rugged case for field deployment.This is important for environmental durability (weatherproofing, vibration resistance).
- The Wio Tracker L1 operates as the mesh node, collecting GPS and possibly telemetry data.
- The XIAO ESP32S3 (at U2) acts as a Wi-Fi/MQTT bridge, receiving data from the Wio Tracker L1 over UART and publishing it to the cloud.
- External telemetry sensors can be connected through M1 or H1 headers (I²C, UART, GPIO), giving flexibility depending on the use case.
- The enclosure makes this a deployable field unit, ideal for smart agriculture, disaster monitoring, or community mesh projects
- Disaster Response: Imagine a rescue team deploying portable nodes into collapsed structures after an earthquake.
Nodes equipped with CO₂ and VOC sensors can detect human presence and provide situational awareness. Even without internet at ground level, the mesh propagates the readings. A single ESP32S3 gateway at basecamp uploads all aggregated data to the cloud for remote crisis coordination.
- Smart Agriculture: Farmers can deploy Wio Tracker L1 units with soil moisture and weather sensors across large fields.
The mesh ensures data from even the most remote sensors is available locally. The MQTT gateway at the farmhouse connects the entire network to the internet, enabling farm-wide dashboards accessible from anywhere.
- Outdoor Communities: Hiking groups or explorers can carry Wio Tracker L1 nodes to share GPS coordinates, altitude, and environmental telemetry. The ESP32S3 at a trailhead or cabin uploads this data to the cloud, giving family members real-time visibility and peace of mind.
- Industrial Monitoring: Factories or mines can monitor air quality, vibration levels, or hazardous gases with a distributed mesh of sensors. The system works on-site without internet, and the gateway ensures all data is synchronized with cloud-based monitoring systems.
This project highlights the power of combining community-driven protocols with Seeed Studio hardware.
By fusing Meshtastic mesh networking with MQTT cloud integration, we create a communication backbone that works
both locally and globally.
Key advantages include:
- Mesh for resilience: Works without cellular or internet in remote or disaster-prone areas.
- MQTT for intelligence: Seamless cloud integration for dashboards, alerts, and global access.
- Modular design: Choose sensors and peripherals based on your scenario.
- Low-power operation: Ideal for solar-powered or battery-powered deployments in the field.
This isn’t just a development kit anymore — it’s a blueprint for next-generation environmental monitoring,
smart agriculture, disaster response, and resilient communication systems.
Project RealizationDue to limited budget for PCB fabrication at this stage, I was unable to produce the final printed circuit board. However, I assembled a fully functional prototype that closely mirrors the intended hardware design and overall concept. This prototype integrates the same key components — including the LoRa module, microcontroller, OLED display, battery, and power management circuitry — on a prototyping board with an equivalent layout.
By doing so, I was able to validate the complete functionality of the gateway, covering radio communication, on-screen status reporting, and power management features. The prototype effectively demonstrates the design’s reliability and serves as a practical proof-of-concept while awaiting the finalized PCB version. The schematic and bill of materials remain consistent, ensuring that this configuration can be easily replicated or adapted by other makers and developers interested in similar projects.
To bring the concept to life without waiting for PCB fabrication, I started by preparing a sturdy plastic enclosure large enough to host both the main board and the antenna connector. Inside, I mounted a piece of perforated prototyping board to serve as the base platform. This board provided mechanical support for the Wio Tracker L1 and allowed flexible wiring between components.
I then placed the Wio Tracker L1 module at the center of the perfboard, aligning its USB-C port and antenna connector to fit neatly within the enclosure. The perfboard was secured using small plastic spacers and screws, ensuring stable support and minimizing movement during operation.
Next, I wired the essential components — the OLED display, power connector, and LiPo battery — using color-coded ribbon cables for clarity and organization. Each connection followed the same routing and pinout as the original PCB design, preserving both electrical integrity and layout consistency. The antenna was mounted through the side wall of the enclosure and fixed firmly with a brass nut for a clean and reliable fit.
After assembling the internal wiring, I performed a continuity check to confirm all signal paths were correct before powering the device. Once connected, the display came to life immediately, showing the Meshtastic interface — a satisfying confirmation that the prototype was fully operational.
After completing the assembly, I conducted a series of functional tests to evaluate both the hardware stability and firmware performance. The prototype was first powered via USB and then switched to battery mode to confirm proper power management and smooth transition between sources. The OLED display initialized correctly, showing the Meshtastic interface with system information such as battery voltage, uptime, and connection status.
The enclosure provided excellent protection during outdoor operation, keeping all internal components stable even under mild vibration or movement. Thermal performance was also stable, with no overheating detected during extended operation.
If you want to make this as a sensor node, my friend Davide already made a great tutorial on how to achieve this on his meshbot project.
You can check his guide here.
Conclusion and Future WorkThis project demonstrates a fully functional prototype of the Wio Tracker L1 Gateway concept, successfully validating both the hardware design and software implementation. Through careful prototyping and testing, all core gateway features — LoRa communication, display output, and power management — have been proven to work reliably in real-world conditions.
While this version is based on a perfboard prototype, the final step for this project will be the fabrication of a dedicated PCB. I plan to translate the current wiring and layout into a professionally designed printed circuit board to enhance durability, simplify assembly, and ensure consistent performance across future builds.
The upcoming PCB version will maintain compatibility with the current firmware and component selection, allowing seamless transition from prototype to production-grade hardware. Once completed, the design files and documentation will be shared publicly so that other makers can reproduce or expand upon this gateway project.
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