Interfels' Digital Biaxial Inclinometer has been specially developed for monitoring lateral movements and deformations of soil, rock including retaining structures. This includes stability of embankments, dams, slopes (natural or man-made); and ground deformation due to tunneling and excavations.

Interfels has utilised the very latest in Bluetooth and MEMS (Micro-Electro-Mechanical) technology in the design of the digital inclinometer systems which provide highly accurate readings.

The system comprises a probe, cable reel and a PDA (Personal Digital Assistant). The probe is fitted with guide wheels and contains two MEMS accelerometers measuring tilts in two perpendicular planes. One measures tilt in the plane of the inclinometer wheels, known as the A axis, and the other measures tilt in a plane perpendicular to that of the wheels and is known as the B axis. It is connected by a graduated cable to the cable reel. A "key fob" activates the saving of readings from the accelerometers. These are transmitted cable-free to the PDA (via Bluetooth transmission) and saved.

In a typical survey, starting from the bottom of the casing the probe tilt readings are taken at 500mm intervals. The first survey establishes the initial profile of the casing and subsequent surveys will show the profile of any ground movement.