Monitoring system for cable transportation


This work deals with a new kind of monitoring tools using MEMS applied to cable transportation. During their lifetime, cables used in transportation fields are suffering from elasticity changes then lengthening for instance. In this way, monitoring their shape along time and following adequate indicators (like the length, the sag…) can alert about first signs of failure.

Our lab at CEA-Leti works for more than ten years on shape capture via inertial sensors.  When placed onto a shape, sensors provide local surface orientations, we thus developed methodology with signal processing and geometrical models to provide virtual surfaces about instrumented shapes.

Our new device is using a single mobile node of inertial sensors and an odometer. Installed for instance near the hangs of a cable car, this system can automatically scan the trajectory of the cable car, thereby the cable shape during all the travel, and provide its length and its sag.

We developed a demonstrator of a cable car on a reduced scale, integrating MEMS (accelerometer) and an odometer, communicating by Bluetooth. A real time application computes and displays the trajectory when the cable car is moving along the cable. When changing the cable tension, we clearly track the shape’s evolution, validating the principle of this cable shape monitoring.