Patent attributes
The bolt tension monitoring system provides remote monitoring of the tension of a bolt, thus allowing for remote monitoring of general structural health and integrity of the fastener. The bolt tension monitoring system includes a housing adapted for being retained on a head of a bolt to be monitored. The system further includes a force transducer positioned between the head of the bolt and a workpiece surface in which the bolt is fastened and measures tension between the head of the bolt and the surface. A controller circuit disposed within the housing calculates a difference between a currently measured tension between the head of the bolt and the workpiece surface and an initially measured tension. A wireless transponder mounted in the housing transmits an alert signal if the calculated difference exceeds a pre-defined threshold value. Actuation and power are provided through radio frequency power harvesting.