Design of a Low-cost IoT-based Wireless Strain Monitoring System for Structural Health Monitoring in Port Portal Cranes

Structural Health Monitoring (SHM) of port portal cranes is critical for ensuring operational safety and longevity. However, traditional wired strain monitoring systems face challenges such as complex installation, high costs, and susceptibility to environmental interference. To overcome these limitations, this paper proposes a low-cost, IoT-based wireless strain monitoring system specifically designed for SHM in port portal cranes. The system adopts a distributed architecture and employs full-bridge strain measurement circuits to achieve high-precision strain sensing. A low-power STM32 microcontroller serves as the core of the data acquisition unit, integrating a dual-layer communication framework that combines LoRa for reliable local transmission and 4G for seamless remote data access. Strain data is transmitted to the Alibaba Cloud platform for real-time storage, analysis, and management. By significantly reducing wiring complexity and maintenance costs while ensuring stable and accurate strain monitoring, the proposed system provides an efficient solution for enhancing the structural integrity assessment of port cranes, demonstrating substantial engineering applicability and value.