Ice Detection Based on Near Infrared Image Analysis

Abstract

In order to detect the ice on aircraft wings, a method based on near infrared image processing is proposed. According to the variety of near-infrared reflectivity, four images of one object are obtained under different detection wavelengths. Water and ice can be distinguished by the different variation trends of near infrared images. In this paper, 1.10μm, 1.16μm, 1.26μm and 1.28μm are selected to be the detection wavelengths. The images of Carbon Fiber Composite material aircraft wings partially covered by water or ice are obtained and analyzed. Parameter D can reflect the variation trend of relative near-infrared reflectivity, so that Parameter D also can be the distinguish basis. The results of the experiment show that the method proposed in this paper is available for ice detection.

Fundamentals of Monitoring Condensation and Frost/Ice Formation in Cold Environments Using Thin-Film Surface-Acoustic-Wave Technology

“…distributed measurement on the surface of the structure or embedded within the structure effect of freezing temperatures on the performance of the sensing elements and low precision impedance impedance of the electrodes changes when ice approaches the electrodes, and then voltage is used to measure the changes 24 sensitive to the presence and thickness of ice great influence of an external attached disturbance on the sensitivity of the measuring unit distributed measurement on the surface of the structure or embedded within the structure optical optical signal of reflection or the refractive index and scattering of the ice to show the ice presence, thickness, and type 25,26 sensitive to the presence, type, thickness, and location of ice on both flat and bent surfaces susceptible to dust complex in structure expensive equipment and difficult to measure the ice mass for thick layers acoustic wave velocity or frequency of propagating waves and amplitude changes when ice accumulates on the blade or sensor's surface 27,28 sensitive to the presence, type, thickness, mass, and location of ice on any surface attenuation and propagation velocity affected by the piezoelectric substrate material distributed measurement on the surface of the structure or embedded within the structure. ultrasonic ultrasonic waves' amplitude and traveling time between the components change with variation of the ice physical variables 29 sensitive to the presence, thickness, and location of ice on both flat and bent surfaces negative effect of the mounting method on the measured structure and susceptible to water and surrounding noise 30 IR thermography electromagnetic wave signal changes form a map of temperature variations 31,32 sensitive to the presence and location of ice on both flat and bent surfaces only the presence of ice detectible and more susceptible to the ambient temperature, surface material, daylight, and weather conditions difficult to access and only applicable to a flat surface As seen from Table 1, ultrasonic and acoustic wave technologies are two promising candidates to monitor ice/ frost formation in a cold environment, and they are commonly based on monitoring of the vibration frequencies with the capability of ice thickness measurement. 15,33,34 Another key advantage of these techniques is that they can also be used as active deicing or antiicing methods.…”

“…Various techniques have been developed to monitor moisture condensation and the formation of frost, snow, and ice, among which ice monitoring is the most studied. − Most techniques for monitoring ice/frost formation are based on in situ measurements of parameter changes for the properties of a specific sensor due to mass loading and changes of the dielectric constants, capacitance, inductance, optical properties, or vibrant frequencies (i.e., using an ultrasonic method or acoustic waves). These methods all have their merits and limitations, − as presented in Table .…”