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Tungsten-Rhenium (W-Re) thin films were grown on alumina ceramic substrate using the magnetron sputtering technique. The feasibility and reliability of the tungsten-rhenium thin film thermocouples application are largely dependent on the adhesion properties between the W-Re film and substrate. In order to get the good adhesion, we researched the effect of magnetron sputtering parameters on adhesion properties of tungsten-rhenium thin film thermocouples. With the help of three factors and three levels orthogonal table, nine orthogonal experiments were designed to study the influences of argon flow rate, sputtering power and vacuum degree on the performance of adhesion. The result showed that the effect of vacuum degree on adhesion properties was the largest, then come sputtering power, while the effect of the argon flow rate was the least and the optimal parameters combination was: argon flow rate 30 Sccm, sputtering power 400 W and vacuum degree 0.7 × 10−6 Torr.

Crystalline cellulose is fully resistant during anaerobic digestion (AD), which brings uncertainty to the use of mathematical models to simulate the dynamic AD process of lignocellulosic waste. In present study, a modified mathematical model, with crystalline cellulose as the primary consideration, was established based on Anaerobic Digestion Model No.1 to simulate the anaerobic bioconversion of vegetable crop residues (VCR) under mesophilic condition. In this model, VCR was divided into inert fraction (contained lignin and crystalline cellulose), as well as biodegradation parts of slowly hydrolysis fraction (SHF, contained hemicellulose and amorphous cellulose), and readily hydrolysis fraction (RHF, contained other organic components in the VCR). Data from a series of batch experiments have been used for the calibration and verification of this model. As a result, the calibrated model was found to match reasonably well the methane production data of three different VCRs, which implies that it was feasible to fractioned VCR into three fractions (SHF, RHF and inert part), and the operation that classified crystalline cellulose into the inert part, while regarded amorphous cellulose as SHF was appropriate. In order to be suitable for simulating the AD process of more other types of lignocellulosic waste, the model needs further modification and inspection.

This paper deals with the problem of area coverage for gas distribution mapping with multiple unmanned aerial vehicles. The area coverage has included two aspect: 1) area allocation of multi micro drones; 2) path planning of each UAV in subarea. The area allocation in this paper is based on the conditions of environment and performance of micro drones: prior gas concentrations of given area and flight time of each UAV. In this paper, there are twice area divisions. First one is used to calculate the density function by equal area grid division method. Other is used in area allocation in order to pertinently complete the task of mapping gas distribution of given area based on density function. Thus, we present an algorithm of area coverage for multiple unmanned aerial vehicles based on the density function in limited time for gas distribution mapping in this paper. The algorithm divides the area into some unequal subareas and achieves the path planning of these areas. Finally the effectiveness of this algorithm is verified by comparing with the equal area coverage algorithm by simulation and analysis.

Most researches of robotic active olfaction are based on two - dimensional environment by far, the experiment of which is too simple to take the impact of turbulent flow on the smoke plume model into consideration. This paper uses the Fluent software to build the smoke plume model in indoor complex environment and generate ASCII data, then import them into the Matlab software to generate gas concentration distribution in the simulation environment, a new evolutionary gradient algorithm that develops the simulation experiment of aerial rotorcraft odor source localization in three-dimensional space is used in the Matlab software and compared with the evolutionary gradient method. The experimental results show that the new algorithm can improve the search efficiency well.

A tungsten-rhenium thin film thermocouples (TFTCs) with ceramic substrate is fabricated and measured in order to establish temperature testing systems. The property of TFTCs with different kind of substrates are measured by and analyzed. The static temperature retention experiment is done to test the thermoelectric characteristics. The experiments showed that TFTCs work at 950K.

The working time of tungsten-rhenium (W-Re) thin film thermocouples (TFTCs) is reduced for the reason of heat volatilization under non oxidizing environment. Influence of magnetron sputtering parameters on thermal volatilization property of tungsten-rhenium TFTCs were discussed by aging test and scanning electron microscope (SEM) test. We used different gas flow rate, sputtering power and the vacuum degree to make 9 samples of TFTCs film. The aging experiment showed that the suitable magnetron sputtering parameters can reduce the heat volatilization rate to 46.5nm/h.

This paper deals with the problem of gas plume tracking by designing and analyzing a system of gas detection and ultrasonic perception for an unmanned aerial vehicle (UAV) in tunnel of GPS-denied environment. Plume concentration information and distance information to wall detected by the system are used to predict a probable direction of drone to next station. Specifically, the idea of integration of gas tracking and three-dimensional (3D) wall-following is introduced to give a probable direction of next spot in terms of the perception system. Moreover, the framework and dynamic modeling of aerial flight system are built according to attitude information of UAV. Then, three types of algorithms are described: first is zigzag to find gas plume, the second is concentration gradient algorithm in tracking odor, and the last one is three-dimensional wall-following navigation method. Finally, the performance capabilities of the flight strategy of integration are validated through real-world experiments in tunnel.

The tungsten-rhenium thin film thermocouples (TFTCs) sensor is designed and optimized based on mechanical properties analysis, the process is optimal designed and the experiment shows the working hours of TFTCs sensor with optimal increasing from 10 minutes to 300 minutes at 900K, and the total work time reach to 600 minutes with a better output voltage when compared with our previously published work and the typically type-S wire thermocouple. Nano-indentation and numerical analysis was used to get the mechanical properties of tungsten-rhenium thin film to make the optimal designed for the dimension parameter of TFTCs. Heat treatment was used to improve the film quality, and the post-processing module was designed to compensate the cold junction temperature and record data. Static thermal test was done to confirm the performance of TFTCs.

It is proposed of a bionic rotor unmanned aerial vehicle (UAV) robot system based on olfactory detection for the monitoring and tracking of airborne in this paper. First, the system processes the data of olfactory according to the combination of onboard controller and the olfactory sensor module. Then, the processed olfactory information is used as the guidance condition of unmanned aerial vehicle direction control, and the autonomous navigation of the UAV is realized by the interpolation navigation control algorithm. At the same time, the flight state and surrounding concentration information of the autonomous rotor are transmitted in real time. Finally, the experimental results show that the design of the olfactory detection system in this paper can effectively accomplish the task of air concentration detection.

In order to solve the problem of unmanned aerial vehicle (UAV) tunnel autonomous flight in GPS-Denied environment, this paper designs the ultrasonic environment perception system and introduces the algorithm of three-dimensional (3D) wall-following navigation. Firstly, the framework of aerial vehicle system and the ultrasonic environment perception system are presented. Then three-dimensional (3D) wall-following navigation algorithm is combined with PID algorithm according to the dynamic model of aerial vehicle. Finally, extensive experiments are carried out in the tunnel where the optimal control parameters are obtained. The experimental results indicate that the UAV can fly in the center of tunnel smoothly and realize autonomous flight steadily in a confined space.

A thermal stress range analysis of tungsten-rhenium thin film thermocouples based on ceramic substrates is presented to analyze the falling off and breakage problems caused by the mismatch of the thermal stresses in thin film thermocouples (TFTCs) and substrate, and nano-indentation experiments are done to measure and calculate the film stress to compare with the simulation results. Optimal design and fabrication of tungsten-rhenium TFTCs based on ceramic substrates is reported. Static high temperature tests are carried out, which show the optimization design can effectively reduce the damage caused by the thermal stress mismatch.

In this paper, Nano-indentation technology is used to test the mechanical property of the tungsten-rhenium thin film, including hardness, elastic modulus and residual stress. The effects of different heat treatment temperature and different substrates on the hardness and elastic modulus of tungsten-rhenium films were studied. We research three substrates which are silicon carbide ceramic, aluminum oxide ceramic and zirconium oxide ceramic. Test results show that the tungsten-rhenium films on aluminum oxide ceramic shows the biggest values of elastic modulus and the smallest on silicon carbide ceramic. However, value of hardness is biggest on zirconium oxide ceramic and smallest on aluminum oxide ceramic. Besides, the heat treatment temperature has high influence on hardness and elastic modulus of tungsten-rhenium film. And under different substrates, the hardness and elastic modulus of film on zirconium oxide ceramic is the most sensitive to heat treatment temperature. By contrast, silicon carbide ceramic is the least.

A tungsten-rhenium thin film thermocouples is designed and fabricated, and the characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. Protective film was presented to prevent from the oxidation and evaporation of tungsten-rhenium TFTCs at high temperature. The experiment shows TFTCs sensor with protective film have an acceptable linearity up to 1370K with a suitable voltage output and can work for half an hour at 1370K, however the TFTCs without protective films break after high temperature constant at 900K.

A tungsten-rhenium thin film thermocouple is designed and fabricated, depending on the principle of thermal-electric effect caused by the high temperature. The characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. The working mechanism and thermo-electric features of the thermocouples are analyzed depending on the simulation results. Then the thin film thermocouples are fabricated and calibrated. The calibration results show that the thin film thermocouples based on the tungsten-rhenium material achieve ideal static characteristics and work well in the practical applications.

Focusing on the background of utilizing magnetic compass in the air-ground amphibious robot system, this paper explores error compensation of magnetic compass in the process of moving on the ground and the air. Based on the error analysis on the air-ground amphibious robot magnetic compass, this paper applies the ellipsoid fitting algorithm for error identification of this model coefficient and thus calibration of magnetic compass is realized in the flight. Finally, through the processing of three sets of data together with the comparison of the traditional empirical Calibration methods, the effectiveness of the proposed method is verified.