Binary Crack Sensor for Steel Girders

We are using a simple binary type of sensor as a low cost way to detect the presence of cracks on steel girders. A small diameter insulated wire is bonded to a steel girder. When a crack reaches a critical width it causes the bonded wire to break. The breaking of the wire causes a large increase in the resistance of the wire. By detecting this change in resistance the presence of a crack can be detected. The sensor is binary in that it only detects the existence of a crack above the critical width or not. We believe this sensor can be made and installed at low cost. This would be of great benefit to infrastructure owners. This technology also provides SMT research with a new product in an area of significant market potential.