In Field Application of an Innovative Sensor for Monitoring Road and Runway Surfaces

Water and ice detection over road and runway surfaces is important to improve traffic safety and to reduce maintenance costs. An innovative low cost capacitive sensor was endowed with an algorithm based on the time derivative of the measured capacitance to indicate the transitions between dry, wet, or icy state of road and runway surfaces. The sensor was investigated theoretically and validated with experiments on field

Experimental Validation of a Sensor Monitoring Ice Formation over a Road Surface

The reliable detection of ice over road surfaces is an important issue for reducing maintenance costs and improving traffic safety. An innovative capacitive sensor was developed to detect the presence of ice on its surface, and its repeatability, stability and reliability were assessed in simulations and experiments described in previous papers. The indications of the sensor are compared in this paper with the objective identification of ice formation or melting over a road surface in laboratory, under dynamic or stationary conditions, using tap water or a solution with 5 % of salt concentration. The sensor provides indications which are in line with the condition of the road surface, with a mean error in the identification of the time instants of ice-wet and wet-ice transitions lower than about 10 and 40 minutes in the case of tap water and salt water, respectively, both under different temperature gradients or in stationary conditions. Moreover, the indication provided by the sensor always anticipates the formation of ice over the road surface

In the Field Application of a New Sensor for Monitoring Road and Runway Surfaces

Water and ice detection over road and runway surfaces is important to improve traffic safety and to reduce maintenance costs. An innovative low cost capacitive sensor was developed to estimate the dry, wet, or icy state of surfaces. The reliability and repeatability of the indications of the sensor were investigated in a previous work based on simulations and experiments in laboratory, together with a preliminary short test in the field. This work is devoted to the study of the indications of 4 sensors (standard or bituminized) during continuous data acquisition in the field (at the Turin Airport) lasted 8 months. The indications of different sensors were highly correlated. As one important problem when measuring in the field is due to dirt and salt spread over the road, a preliminary study on the effect of different salt concentrations in the water covering the surface of the sensor was performed. Both simulations and laboratory tests showed that the sensor is not affected by the presence of salt in the water. Considering data measured in the field, the estimated condition of the road provided by the sensors was found to be consistent with the METAR (METeorological Aerodrome Report) message of the Turin Airport, for the whole period of investigation. Correlation was found between data from the sensors and rain, fog, and snowfall. The beginning formation of ice identified by the sensor was found to be in some agreement with the indication of a mathematical model of ice prediction from meteorological data. The possibility of using the indications of the sensor together with weather data to train an algorithm providing a more precise prediction of ice formation is discussed