Inclinometers

An inclinometer, or tilt sensor, is a device that measures the angle of an object or surface with respect to gravity. It can determine how much an object is tilted from the horizontal, and may provide measurements for a single tilt axis or two perpendicular axes.

Inclinometers come in several forms. Mechanical inclinometers rely on a bubble or a free-surface liquid, a pendulum, or a stylus in a curved tube to indicate tilt. Electronic inclinometers use microelectromechanical systems (MEMS) accelerometers, capacitive sensors, or combinations with gyroscopes to infer orientation from the gravity vector. Optical inclinometers use light and reference targets, typically in specialized applications.

Common applications include civil and geotechnical monitoring (tracking slope movement, settlement, and deformation), structural health monitoring of buildings, bridges, and towers, and attitude sensing in aviation, vehicles, and robotics. In borehole geotechnical work, electronic inclinometer probes sense lateral movement over time to assess stability.

Operation is typically expressed as a tilt angle in degrees, around one or more axes. High-end mechanical instruments can resolve very small angles; MEMS devices commonly achieve tens of arcminutes to hundredths of a degree. Performance is influenced by temperature, vibration, and calibration; many systems provide self-calibration or require periodic reference checks and data logging for trend analysis.

Inclinometers continue to evolve with advances in sensor fusion and wireless data transmission, expanding their use in smart infrastructure and automated systems.