Screw connections are a widespread and standardized joining technology and represent a simple, efficient and universal assembly option. They are aused at critical points such as on bridges, wind turbines or machinery on production lines. These crritical points in particular often require permanent monitoring of the screw connection's quality and reliability.
Wireless and self-powered monitoring of screw connections
The smart screw connection is a fully integrated IoT device that enables wireless and energy-independent monitoring of screw connections. The DiaForce® layer integrated into the sensor makes it possible to determine the preload force of the screw connection as well as the temperature at the assembly location in order to detect pressure changes on the screw. The acquired sensor data is transmitted wirelessly and securely to a cloud-connected monitoring entity using mioty® transmission technology. Before assembly, the screws are configured in the FunkeyBox tamper-proof programming unit, where they are each given their own key. This makes their sensor data attack-proof during transmission to the base station or the backend. Energy harvesting guarantees an independent power supply. Inside the screw is a thermogenerator that generates electrical power from the smallest temperature gradients at the screw’s connection, which makes sensor operations energy-independent and self-powered. Alternatively, the sensor and transmitter can be powered by a solar cell or battery.
Outstanding features of the »Smart Screw Connection«:
- DiaForce® sensor layer system for high-resolution measurement of static and dynamic forces and temperatures
- mioty® LPWAN radio transmission to ensure energy-efficient, reliable data transmission over long distances with a high number of radio nodes communicating in parallel
- Energy harvesting technology and energy management for independent operation using power from the environment, without battery changes or wired power supply
- Robust interfaces for configuration and status requests via RFID interface or LPWAN return channel
- Innovative antenna technology for efficient communication even in metallic environments
- Tamper-proof sensors thanks to hardened hardware
- Secure communication with the lowest possible energy consumption using efficient cryptographic calculations
- Secure commissioning thanks to efficient distribution of individual keys (FunkeyBox)
- Sensor characterization and optimization of the screw geometry