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Air speed, the angle of attack and the angle of sideslip are fundamental parameters in the control of flying bodies. Conventional detection techniques use sensors that may protrude outside the aircraft and be too bulky and intrusive for small unmanned air vehicles and micro air vehicles. In this paper, a novel and practical methodology by which the flight parameters are inferred from multiple hot-film flow speed sensors mounted on the surface of the wing is presented. In order to get a good mathematical relation between the readings of the sensors and the flight parameters, we use a back-propagation neural network to model the relationship. The methodology is validated by wind tunnel experiments, and the experimental results are presented.

This paper demonstrates a highly sensitive humidity sensor based on carbon nanotube and poly (dimethyldiallylammonium chloride) composite films. The composite film is deposited between interdigitated electrodes on a Si SiO 2 substrate through layer-by-layer self-assembly technique. The resistance stability of the composite film is effectively improved through thermal annealing, and I-V characteristic of the film exhibits a very good linear behavior. The resistance increases exponentially with relative humidity from 20% to 98%, and a much higher sensitivity in comparison with pure carbon nanotube networks is achieved. With temperature increased, the water vapor density versus RH shifts upwards, while the resistance is reduced downwards. The resistance is dependent on temperatures with a negative coefficient. The composite films with multiwalled carbon nanotubes show an adjacent sensitivity, compared with the single-walled carbon nanotube composite films. The experimental results show that the humidity sensors have a fast response and a short recovery time, and their response is reversible. A simple model is proposed to explain the change of composite film resistance with humidity. The carbon nanotubes junctions may play a more important role in the overall resistance change for water molecule absorption.Index Terms-Carbon nanotube (CNT), composite film, humidity sensitivity, layer-by-layer (LbL) self-assembly, poly (dimethyldiallylammonium chloride).