STM32-Based IoT Smart Vibration Monitoring Device Development

Titan Industrial Solution (the client) is an international manufacturer of large-scale heavy equipment/machinery, with many production facilities throughout the world that have automation systems such as conveyor type systems, pumping stations, and CNC machines on site.

They experienced unpredictable unplanned breakdowns of their machinery which resulted in costly downtime and unforeseen maintenance. Therefore, they were looking for an integrated solution that could give them real-time visibility of machine health and help them predict failure before the problem occurs.

To evaluate these problems, we engineered a Smart Vibration Monitoring Tool through the use of STM32 Wireless MCU's. The function of this device was to allow for continuous real-time monitoring of machine vibrations, temperature, and operational status.

The system design requirements encompassed end to end functionality, including the hardware design, embedded firmware, industrial design casing, cloud integration, and complete software solutions on desktop, web, and mobile platforms.

Key project objectives included:

• Real-time vibration and temperature monitoring
• Wireless data transmission with low power consumption
• Predictive analytics for machine maintenance
• User-friendly dashboards and notifications
• SDK and REST API for third-party integration

We provide an end-to-end Industrial Internet of Things (IoT) solution that encompasses all layers of technology.

1. PCB & Hardware:

Core Controller:

The STM32WB55 Bluetooth Low Energy (BLE) microcontroller comes with many features such as Bluetooth Low Energy connectivity, Sub-1GHz radio capability, low power consumption, high performance, and has proven to be very reliable in an industrial setting.

Sensors:

• Motion: Tri-Axis accelerometer with MEMs-based design that detects vibration;
• Temperature: Low-cost surface mounted thermistor with high accuracy, provides reliable temperature measurements to ± 0.1°C;
• Optional: Current and voltage sensing devices allow the measurement of electrical loads;

PCB Design:

Four separate multi-layer industrial PCBs have been designed based on isolated power circuit layouts which have increased protection to counter high levels of Electro-Magnetic Interference (EMI) found in industrial factory environments.

Each PCB contains EMI filters and connectors rated for industrial use, ensuring long-lasting performance.

Power Management:

A rechargeable lithium-ion battery provides a charge circuit along with various energy harvesting alternatives so as to provide long-term low maintenance operation.

Industrial Enclosure:

Casing designed with an Ingress Protection (IP67) rating using high-temperature resistant and shock resistant materials.

Provides protection to the IoT solution from dust and high temperatures typically found in factory environments.

We delivered a fully integrated Industrial IoT solution covering every layer of technology.

2. Firmware development of embedded controllers

Real-time data acquisition:

The firmware was developed on the STM32RTOS, which allows for a sample rate of vibration at 1 kHz. The firmware also processes the sample data to be used to detect abnormalities.

Wireless Protocols:

A mesh network using BLE mesh to communicate on-site and LoRaWAN for connecting to all of the facilities and equipment for longer-distance coverage.

Local processing:

The STM32 microcontroller is programmed with Edge AI algorithms so that they can calculate the RMS value of the sampled vibration signal, detect abnormal vibrations and reduce excess data traffic to the cloud.

Firmware over-the-air (FOTA):

FOTA is a secure method of updating firmware via air for embedded processors.

3. Manufacturing & Assembly

• Complete PCB assembly using SMT and THT techniques
• Integration of sensors with precise calibration for industrial vibration standards
• Industrial casing injection molding and assembly
• Rigorous quality testing for vibration, temperature, and wireless performance

4. Architecture in the Cloud and Backend

Cloud Services:

Using AWS IoT Core, devices are securely registered, data is ingested, and data is sent to a central point for real-time telemetry.

The Data Pipeline:

• Sensor data for temperature and vibration is streamed to an MQTT Broker.
• All high-frequency temperate and vibration sensor data is stored in a time series database (InfluxDB).
• Data normalization and anomaly detection pipeline is created using Microservices written in Python.

Analysis:

Predictive maintenance algorithms can be built using the data generated from vibration reading over time to calculate expected time remaining to life (RUL).

Data Security:

The entire encryption system is an end-to-end system using TLS encryption, token-based authentication, and Role-Based Access Control. Compliance can be achieved in a variety of manufacturing environments.

5. Software & Application Development

Desktop Application:

Windows and Linux-compatible app providing detailed dashboards, historical data visualization, and alert management. Developed using Electron and ReactJS.

Web Application:

Industrial-grade portal with real-time monitoring, user management, analytics dashboards, and reporting. Tech stack: Angular, Node.js, and PostgreSQL.

Mobile Application:

Cross-platform mobile app using Flutter for instant alerts, machine status monitoring, and push notifications.

REST APIs & SDKs:

• REST APIs for integration with ERP and MES systems
• SDKs for C#, Python, and Java to enable custom integrations and automation

Alert & Notification System:

SMS, email, and mobile push notifications for early warning and maintenance scheduling

6. AI & ML Integration

Anomaly Detection:

Added vibration analysis at the edge to identify mechanical issues before sending notifications to cloud.

Predictive Maintenance:

Using cloud-based Machine Learning models (ML) of historical sensor data to accurately predict failure and reduce unplanned downtime by up to 30%.

7. Deployment & Monitoring

• Devices are deployed in multiple production sites with secure onboarding.
• Real-time dashboards for plant managers and maintenance personnel.
• Automated device health monitoring, which sends alerts regarding low battery, sensor failure, or connectivity issues.

Solution Delivery:

The entire project was designed to provide a comprehensive solution, beginning with PCB design through cloud integration, and covering all phases of the project (end-to-end).

Improved Equipment Uptime:

In the first three months of the forecasted equipment failure, the use of predictive analytics resulted in a more than 25% reduction in unplanned downtimes.

Scalable IoT Network:

By using both a mesh and LoRaWAN network, hundreds of IoT-connected devices can communicate and work together on a customer factory floor.

Secure and Compliant:

The project was successfully completed while fully complying with all required industrial cybersecurity standards, i.e., Encryption, Role-based access.

Client-side SDK/API support:

This solution provided the technical ability for their IT teams to integrate the monitoring information from the connected assets into their existing ERP and MES systems.

High-Frequency Vibration Data Handling:

Implemented edge-level FFT processing to reduce cloud traffic and maintain real-time monitoring.

Harsh Industrial Environment:

Designed IP67 casing and industrial-grade PCB to withstand high temperatures, dust, and electromagnetic interference.

Wireless Connectivity Issues:

Deployed BLE Mesh and LoRaWAN fallback to ensure reliable connectivity across the factory.

The project illustrates our ability to provide industrial IoT Solutions from start-to-finish.

Through the combination of STM32-based wireless devices, rugged operating systems, an industrial-strength PCB and airframe, cloud-based services, AI-based predictive analytics, and full-featured application software for multiple platforms, we delivered a system that significantly changed Titan Industrial Solutions' predictive maintenance strategy.

The result of this project was more than just improved operational efficiency, it also serves to position Titan Industrial Solutions for the future growth of industrial IoT through their operations around the world.