Environmental monitoring is a critical aspect of protecting and managing natural resources, and the advancements in sensor technology are enabling more efficient, reliable, and accessible data collection. Bryce Syme, Senior Instrumentation Engineer at the Scottish Environment Protection Agency (SEPA), has been at the forefront of this innovation, recently developing a cutting-edge water level sensor that promises to enhance the agency’s environmental monitoring capabilities.
The Power of Simplicity and Reliability
In his latest project, Bryce has successfully integrated various components into a seamless, “fit and forget” solution that monitors water levels, air temperature, and humidity with remarkable precision. The backbone of this sensor system is the Dragino Technology Co., Limited kit, supplied by UKIoT, which Syme commends for its ease of use and reliability.
The sensor is designed to be a simple, standalone device, requiring minimal maintenance once deployed. It features a hot-swappable sensor pack that includes options for air temperature, humidity, and water temperature sensors. The sensors are housed in a Stevenson screen-style enclosure, ensuring durability and optimal environmental protection. The ability to hot-swap sensors without disrupting the overall system is a standout feature, enabling quick and easy upgrades or replacements in the field.
Key Components and Specifications
The water level sensor system comprises several high-performance components, each selected for its specific capabilities:
• Dragino RS485-NB and NBIoT Modules: These modules form the core communication system, ensuring reliable data transmission via narrowband IoT (NB-IoT). The modules are also integral to over-the-air (OTA) firmware updates, facilitated by the Seeed Studio Xiao ESP32-C3 sensor interface.
• MaxBotix MBX7388 Level Sensor: This ultrasonic sensor offers a 0-10 meter range with a 1mm resolution, providing precise water level measurements. Syme notes the sensor’s outstanding performance, particularly its ability to deliver smooth and accurate distance values, making it a critical part of the system’s success.
• Sensirion SHT85 Sensor: For air temperature and humidity measurements, the SHT85 offers high accuracy and reliability, ensuring that environmental data is consistently precise.
• Seeed Studio Xiao ESP32-C3: This microcontroller handles sensor readings and data processing, ensuring that the system operates smoothly and efficiently. It also plays a key role in managing OTA updates, allowing for easy firmware upgrades in the field.
• Fibox TEMPO TA 131007 Enclosure: The sensor system is housed in a robust Fibox enclosure, which provides exceptional protection against harsh environmental conditions.
• DKCELL 6600mAh 18650 Rechargeable Cell and 5W PV Panel: Powering the entire system is a rechargeable battery supported by a 5W solar panel, ensuring that the sensor remains operational without the need for frequent battery changes, even in remote locations.
• MAXIM DS18B20 Water Temperature Sensor: This sensor is included as an optional component for monitoring water temperature, adding another layer of environmental data collection.
Bench Testing and Field Deployment
The development process has been rigorous, with extensive bench testing to ensure the system’s reliability before field deployment. The Seeed Studio Xiao ESP32-C3 module has proven particularly adept at handling sensor readings, including smoothing out the data from the MaxBotix ultrasonic sensor. Data transmission success rates have been impressive, with a 96% success rate in NB-IoT data transmission during testing, and 100% data capture over multiple readings.
Despite an accidental drop test, the sensors remained fully operational, demonstrating their durability. The first two units have now been deployed in the field, and early indications suggest that the sensors are performing exceptionally well, delivering reliable data to SEPA’s corporate timeseries database via an AWS API.
Achieving Key Objectives
Syme set out with clear goals for this project, all of which have been met:
• Fit and Forget: The sensor is designed for long-term deployment with minimal maintenance.
• High Precision: The system achieves 1mm resolution in water level measurements and high accuracy in temperature and humidity readings.
• Self-Sustaining Power: The combination of a rechargeable battery and solar panel eliminates the need for regular battery replacements.
• Frequent Data Collection: The sensor takes readings and transmits data every 15 minutes, providing timely and detailed environmental data.
• Cost-Effective: There are no ongoing subscription costs, making the system a financially sustainable solution.
• Hot Swappable Sensor Module: The sensor pack can be easily replaced or upgraded in the field, adding to its longevity and adaptability.
• Corporate Database Integration: The system integrates seamlessly with SEPA’s existing data infrastructure.
Looking Forward
With the successful deployment of the initial units, Bryce is now looking to scale up production, with plans to deploy a larger batch of sensors in the near future. Additionally, there are exciting developments on the horizon, including a radar sensor upgrade and a version of the sensor system that incorporates satellite communications for use in even more remote locations.
Bryce Syme’s work with the Dragino Technology Co., Limited kit, Fibox TEMPO Electrical Enclosure, and other advanced components exemplifies the potential for innovative, reliable, and cost-effective solutions in environmental monitoring. As SEPA continues to deploy these sensors, the data collected will play a crucial role in safeguarding Scotland’s natural environment, demonstrating the significant impact of cutting-edge technology in the field.
Article provided by Fibox
