A capacitive ice layer detection system suitable for autonomous inspection of runways using an ROV

This paper presents a simple and efficient non-contact ice layer detection system. The proposed scheme is based on a capacitive sensing principle. Many accidents have been reported in the winter due slippery roads and runways. Presence of ice layers on the surface of runways and roads is one of the important reasons for slippery conditions. Continuous inspection of the runway will be required in such conditions to avoid accidents. Frequent human inspections may be inefficient and may fail to see thin transparent layers of ice. A capacitive sensor that can be integrated into an ROV for automated inspection of ice layers in important locations like runways is proposed in this paper. The sensor is mounted to the bottom part of the body of an ROV. Relative permittivity of ice is a function of excitation frequency. A multi-frequency excitation is employed to exploit this property and detect presence of ice layers reliably. A prototype of capacitive ice detector has been developed and integrated into an ROV. Prototype has been tested on various types of floors with ice layer, in a climatic chamber. Tests were also performed on roadways. From the test results, it has been observed that the developed system successfully detected ice layers as thin as 1 mm.