Table of contents

ICMAE 2016 was held in Hong Kong during December 28-30, 2016. ICMAE 2016 was organized by Hong Kong Society of Mechanical Engineers (HKSME). The conference provides a useful and wide platform both for display the latest research and for exchange of research results and thoughts in broad Mechanical and Aeronautical Engineering. The participants of the conference were from almost every part of the world, with background of either academia or industry, even well-known enterprise. The success and prosperity of the conference is reflected high level of the papers received.

The proceedings are a compilation of the accepted papers and represent an interesting outcome of the conference. This proceeding covers 4 chapters: Aeronautical Science, Aeronautical Systems, Mechanical Science and Mechanical Systems.

We would like to acknowledge all of those who supported ICMAE 2016. Each individual and institutional help were very important for the success of this conference. Especially we would like to thank the organizing committee for their valuable advices in the organization and helpful peer review of the papers.

We sincerely hope that ICMAE 2016 will be a forum for excellent discussions that will put forward new ideas and promote collaborative researches. We are sure that the proceedings will serve as an important research source of references and the knowledge, which will lead to not only scientific and engineering progress but also other new products and processes.

Prof. Ian McAndrew, Embry Riddle Aeronautical University, UK

Prof. Andrew Rae, University of the Highlands and Islands, UK

Advisory Committee Chairs

Prof. Andrew Rae, University of the Highlands and Islands, UK

Prof. Ian McAndrew, Embry Riddle Aeronautical University, UK

Conference Committee Chairs

Prof. WONG Chee How, Nanyang Technological University, Singapore

Prof. Christopher Y. H. CHAO, Hong Kong University of Science and Technology, Hong Kong

Prof. Dan Zhang,York University, Canada

Prof. Cheng Li, The Hong Kong Polytechnic University, Hong Kong

Program Committee Chairs

Prof. ERASMO CARRERA, Politecnico di Torino, Italy

Prof. Matthew Parkinson,Pennsylvania State University, USA

International Technical Committee

Prof. Musa bin Mailah, Universiti Teknologi Malaysia, Malaysia

Prof. Chee-Meng Chew, National University of Singapore

Debra T. Bourdeau, Embry Riddle Aeronautical University, UK

Dr.David Scott Cross, Embry Riddle Aeronautical University, UK

Dr. Michele Ferlauto, Politecnico di Torino, Italy

Prof. Lin Shih-Chieh, National Tsing Hua University, Taiwan

Prof. Do, Hyungrok,Seoul National University, Korea

Prof. Yu-Ren Wu,National Central University, Taiwan

Prof. Nasir Hayat, University of Engineering and Technology, Pakistan

Prof. Ugur GUVEN, University of petroleum & energy studies, USA

Dr. TRAN Anh Tuan, Nanyang Technology University, Singapore

Dr. VINOTHKUMAR SIVALINGAM, Anna University, India

Dr. Farzad Ismail, Universiti Sains Malaysia, Malaysia

Dr. Eltayeb Eljack, King AbdulAziz University, Saudi Arabia

Dr. P.Sivaprakash, A.S.L.Pauls College of Engineering and Technology, India

Elena Navarro, Embry Riddle Aeronautical University, USA

Dr. Satish S. Chinchanikar, Department of Mechanical Engineering, VIIT, India

Dr. Redouane Zitoune, Clément Ader Institute of Toulouse University, France

Dr. Anis Hor, Clément Ader Institute of ISAE - SUPAERO, Toulouse, France

Dr. Vijayan Krishnaraj, PSG College of Coimbatore, India

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

This paper presents a numerical investigation on the three-dimensional interaction between two bow shock waves in two environments, i.e. ground high-enthalpy wind tunnel test and real space flight, using Fluent 15.0. The first bow shock wave, also called induced shock wave, which is generated by the leading edge of a hypersonic vehicle. The other bow shock wave can be deemed objective shock wave, which is generated by the cowl clip of hypersonic inlet, and in this paper the inlet is represented by a wedge shaped nose cone. The interaction performances including flow field structures, aerodynamic pressure and heating are analyzed and compared between the ground test and the real space flight. Through the analysis and comparison, we can find the following important phenomena: 1) Three-dimensional complicated flow structures appear in both cases, but only in the real space flight condition, a local two-dimensional type IV interaction appears; 2) The heat flux and pressure in the interaction region are much larger than those in the no-interaction region in both cases, but the peak values of the heat flux and pressure in real space flight are smaller than those in ground test. 3) The interaction region on the objective surface are different in the two cases, and there is a peak value displacement of 3 mm along the stagnation line.

The nonlinear model for turbofan engine above idle state based on NARX is studied. Above all, the data sets for the JT9D engine from existing model are obtained via simulation. Then, a nonlinear modeling scheme based on NARX is proposed and several models with different parameters are built according to the former data sets. Finally, the simulations have been taken to verify the precise and dynamic performance the models, the results show that the NARX model can well reflect the dynamics characteristic of the turbofan engine with high accuracy.

Microchannel for macro geometry application is gaining popularity particularly in aerospace, biomedical and photovoltaic. A novel method of employing microchannel in macro geometry at lower cost using conventional machining methods has been developed. A solid cylinder on outer diameter 19.4 mm is placed concentrically into a copper pipe of inner diameter 20 mm, forming an annular microchannel with 300 μm gap. This study takes a step further by introducing surface profile of different heights on the surface of solid cylinder and investigating the effect on two main design objectives- increasing heat removal capability at same pumping power and reducing pumping power for the same heat removal duty. Four surface profiles -parallel fins as well as fins with height of 0.1, 0.2 and 0.3 mm, were investigated experimentally at constant heat flux at Reynolds number from 690 to 4600. The amount of fluid in the microchannel, channel length of 30 mm, bifurcating angle of 75 degrees and mean hydraulic diameter of 600 μm are kept as constant parameters. A plain insert is used as benchmark for comparison of enhancement. In this study, insert with fins of 0.3 mm attains the highest enhancement of 43 percent increment in heat transfer as compared to plain insert using the same pumping power. While keeping the heat removal duty constant, the same insert is able to perform the duty using less than 50 percent the pumping power required by the plain insert at low Reynolds numbers.

The technology of Bank-to-Turn has been recognized as an attractive direction due to their significance for the control of hypersonic glide vehicle. Strong coupling existing among pitch, yaw and roll channel was a great challenge for banking to turn, and thus a novel global sliding mode controller was designed for hypersonic glider in this paper. Considering the coupling among channels as interference, we can use invariance principle of sliding mode motion to realize the decoupling control. The global sliding mode control system could eliminate the stage of reaching, which can lead to the realization of whole systematic process decoupling control. When the global sliding mode factor was designed, a minimum norm pole assignment method of the sliding mode matrix was introduced to improve the robustness of the system. The method of continuity of symbolic function was adopted to overcome the chatter, which furtherly modify the transient performance of the system. The simulation results show that this method has good performance of three channel decoupling control and guidance command tracking. And it can meet the requirements of the dynamic performance of the system.

The precision of MEMS gyroscope is reduced by random drift error. This paper applied time series analysis to model random drift error of MEMS gyroscope. Based on the model established, Kalman filter was employed to compensate for the error. To overcome the disadvantages of conventional Kalman filter, Sage-Husa adaptive filtering algorithm was utilized to improve the accuracy of filtering results and the orthogonal property of innovation in the process of filtering was utilized to deal with outliers. The results showed that, compared with conventional Kalman filter, the modified filter can not only enhance filter accuracy, but also resist to outliers and this assured the stability of filtering thus improving the performance of gyroscopes.

Aiming at the multiple UAVs' cooperation in the complex environment, detailed analysis about targets assignment model is made in the paper. Firstly, three basic situations are discussed according to the quantitative relationship between the UAVs and the targets. Then in order to make the targets model more practical, the probability that the UAVs' damage is also taken into consideration. Following, basic particle swarm optimization algorithm is adopted to solve the model which has great performance in efficiency and convergence. Finally, three-dimensional environment is simulated to verify the model. Simulation results show that the model is practical and close to the actual environment.

The present study aims to investigate numerically the flow control possibility using a synthetic jet actuation over a bi-dimensional NACA0015 airfoil manoeuvring at a highly turbulent flow (8.9e10⁵ Reynolds to chord number). The 2-D flow behaviour was computed using the ANSYS Fluent commercial code. The so-called Reynolds Averaged Navier-Stocks (RANS) approach has been tested for one (Spalat-Allmaras S-A) and two (K-ε) transport equations for the turbulence modelling. Both present a weakness to predict the stall angle effectively. The S-A lift coefficient slope seems to be the closest to the experimental data. The synthetic jet control exhibits an extraordinary lift coefficient enhancement at high Angles Of Attack (AOA) but seems to be less obvious at low AOA, where the flow is still attached. A synthetic jet of a Strouhal (St = 2) and momentum (Cμ of 0.56%), delays the stall onset from 15 to 19deg with enhancing the lift coefficient by 40%. The actual work has been enriched by studying the effect of the jet's frequency and momentum on the lift temporal signal. Also, the interaction between the mean flow and the synthetic jet structures topology was undertaken.

The present study investigates the low-frequency flow oscillation phenomenon near stall conditions for NACA0012 aerofoil at Reynolds number of 9 × 10⁴, Mach number of and angle of attack of 11.0°. The phenomenon is clearly captured in the time histories of aerodynamic coefficients. Statistical and spectral analysis are carried out for time histories of aerodynamic coefficients. Qualitative study is performed to investigate the unsteady behaviour of laminar separation bubble over one low-frequency cycle.

In this paper, the laminar flame velocity and temperature exponent diluted dimethyl ether (DME) air mixtures are reported. Laminar premixed mixture of DME-air with volumetric dilutions of carbon dioxides (CO₂) and nitrogen (N₂) are considered. Experiments were conducted using a preheated mesoscale high aspect-ratio diverging channel with inlet dimensions of 25 mm × 2 mm. In this method, flame velocities are extracted from planar flames that were stabilized near adiabatic conditions inside the channel. The flame velocities are then plotted against the ratio of mixture temperature and the initial reference temperature. A non-linear power law regression is observed suitable. This regression analysis gives the laminar flame velocity at the initial reference temperature and temperature exponent. Decrease in the laminar flame velocity and increase in temperature exponent is observed for CO₂ and N₂ diluted mixtures. The addition of CO₂ has profound influence when compared to N₂ addition on both flame velocity and temperature exponent. Numerical prediction of the similar mixture using a detailed reaction mechanism is obtained. The computational mechanism predicts higher magnitudes for laminar flame velocity and smaller magnitudes of temperature exponent compared to experimental data.

A simulated aircraft fuel tank inerting system was established and experiments were conducted to investigate the performance of the system. The system uses hollow fiber membrane which is widely used in aircraft as the air separation device and a simplified 20% scale multi compartment fuel tank as the inerting object. Experiments were carried out to investigate the influences of different operating parameters on the inerting effectiveness of the system, including NEA (nitrogen-enriched air) flow rate, NEA oxygen concentration, NEA distribution, pressure of bleeding air and fuel load of the tank. Results showed that for the multi compartment fuel tank, concentrated flow washing inerting would cause great differences throughout the distribution of oxygen concentration in the fuel tank, and inerting dead zone would exist. The inerting effectiveness was greatly improved and the ullage oxygen concentration of the tank would reduce to 12% successfully when NEA entered three compartments evenly. The time span of a complete inerting process reduced obviously with increasing NEA flow rate and decreasing NEA concentration, but the trend became weaker gradually. However, the reduction of NEA concentration will decrease the utilization efficiency of the bleeding air. In addition, the time span can also be reduced by raising the pressure of bleeding air, which will improve the bleeding air utilization efficiency at the same time. The time span decreases linearly as the fuel load increases.

By analyzing the development status of several typical solar powered unmanned aerial vehicles (UAV) at home and abroad, the key technologies involved in the design and manufacture of solar powered UAV and the technical difficulties need to be solved at present are obtained. It is pointed out that with the improvement of energy system efficiency, advanced aerodynamic configuration design, realization of high applicability flight stability and control system, breakthrough of efficient propulsion system, the application prospect of solar powered UAV will be more extensive.

A parametric study of the effect of rectangular antisymmetric pulsed control jets on the jet mixing with different pulse frequency is conducted using RANS simulation. The mean centerline potential core length and the axial velocity contours of the main jet at different downstream positions (x/D) is investigated and discussed in detail. When the antisymmetric pulsed control jets are injected into the main flow, a starting vortex is observed in the axial velocity contours on x-z plane, which does not exist when the control jets are symmetric steady (St=0). The factors that have effect on the jet mixing are analyzed and described in detail, and the jet/ambient air interfacial area is found to play an important role in jet mixing. The best mixing effect can be reached at the same mass flow ratio of the main flow to the control jets if a proper pulse frequency of the control jets is used.

Symmetric synthetic jet is used to stimulate a Mach number 0.9 and high temperature jet for the mixing enhancement. The movement of the piston-type synthetic jet is simulated by dynamic mesh based on URANS numerical methods. Jet flapping, streamwise vortex and geometric axis transformation are the jet mixing mechanism. However, the jet mixing enhancement effect depends on penetration area, which consists of penetration depth and spanwise. And the penetration area is determined by actuator nozzle diameter and blowing jet momentum. In addition, a 54% reduction in potential core length and maximum 45.8K decrease in potential temperature are achieved.

Pressure bearing has been acting an important role in the EVA (extravehicular activity) suit as a main mobility component. EVA suit bearing has its unique traits on the material, dustproof design, seal, interface, lubrication, load and performance. This paper states the peculiarity and development of the pressure bearing on the construction design element, load and failure mode, and performance and test from the point view of structure design. The status and effect of EVA suit pressure bearing is introduced in the paper. This analysis method can provide reference value for our country's EVA suit pressure bearing design and development.

With the development of computer vision, virtual reality has been applied in astronaut virtual training. As an advanced optic equipment to track hand, Leap Motion can provide precise and fluid tracking of hands. Leap Motion is suitable to be used as gesture input device in astronaut virtual training. This paper built an astronaut virtual training based Leap Motion, and established the mathematics model of hands occlusion. At last the ability of Leap Motion to handle occlusion was analysed. A virtual assembly simulation platform was developed for astronaut training, and occlusion gesture would influence the recognition process. The experimental result can guide astronaut virtual training.

Quadrotors are gaining an increasing interest in public and extensively explored in recent years. In many situations, a team of quadrotors is desired to operate in a certain shape, which is also called formation. In this paper, a linear PID controller is used to control each single quadrotor and a slide mode controller is adopted to solve the formation flying problem which employs the leader-follower structure. The formation simulations are run in the Matlab/Simulink environment to evaluate the performance of control laws.

A prediction method of surface temperature and runback ice for a three-dimensional hot air anti-icing system was proposed. Computational approach to realize this method was introduced. Both the external and internal flows were separately calculated, results of which were set as boundary conditions of heat conduction computation in airfoil skin. The results of external and internal flow calculations show that the effect of surface temperature on convective heat transfer coefficients and local droplet collection efficiency is negligible and the calculations can be decoupled. The prediction method based on heat flux was used to calculate surface temperature and runback ice results. The results show that, the effects of LWC and Mach number are much more significant than the effect of external flow temperature. The surface temperature at impinging interaction point is more sensitive to the change of external conditions than that at stagnation point. The surface temperature changes significantly with changing Mach number because both the mass rate of droplet and the impact limit are changed.

Global Positioning System (GPS) has become part of many applications in life. In mountainous terrains and around buildings, GPS reception is compromised. In dense urban canyons, signals bounce off the buildings creating multipath reception and provide erroneous measurements. To overcome GPS bandwidth and signal fading problems, Navigation solutions are built on GPS measurements fused with inertial sensors to provide dead reckoning (DR) based position solution. Solution for land vehicle Navigation System using GPS, inertial sensor and odometer is presented. The sensors fusion is performed based on conventional, sequential (SKF) and square root Kalman (SRKF) filters. SRKF based on Cheolesky factorization for covariance matrix P. Simulations are performed on real data, with precisely known covariance's to simulate mathematical stability, performance and processing time required by each method on a high end microprocessor. The results demonstrate integrated system using SRKF has better performance in stability and estimation accuracy than conventional and sequential filter.

The conventional Kalman filter (KF) algorithm is suitable if the characteristic noise covariance for states as well as measurements is readily known but in most cases these are unknown. Similarly robustness is required instead of smoothing if states are changing abruptly. Such an adaptive as well as robust Kalman filter is vital for many real time applications, like target tracking and navigating aerial vehicles. A number of adaptive as well as robust Kalman filtering methods are available in the literature. In order to investigate the performance of some of these methods, we have selected three different Kalman filters, namely Sage Husa KF, Modified Adaptive Robust KF and Adaptively Robust KF, which are easily simulate able as well as implementable for real time applications. These methods are simulated for land based vehicle and the results are compared with conventional Kalman filter. Results show that the Modified Adaptive Robust KF is best amongst the selected methods and can be used for Navigation applications.

This paper presents the study of the system identification and controller design for an unmanned helicopter using the integration of Proportional Integral (PI) and Model Predictive Control (MPC). Since the dynamic model of a helicopter is highly nonlinear and contains many uncertainties, the system identification and control are challenging and complicated. To accelerate the development, the autonomous flight and trajectory tracking of an unmanned helicopter, this study first setup a software simulation environment of the helicopter using the X-Plane flight simulator. The prediction-error minimization (PEM) and subspace methods were applied in this study to identify the dynamic model of the interested flight trim conditions. The lateral, longitudinal, heave, and yaw dynamic models were predicted by using the System Identification Toolbox of MATLAB. To enhance the stability and eliminate the uncertainty of the control system, the Integration of Proportional Integral (PI) and MPC were introduced. The developed control system was then applied to perform the trajectory tracking of a helicopter. The simulation results show that the performance of the proposed approach can track the desired trajectory.

In this article, an optimal state is estimated using the moving horizon estimation technique (MHE), based on the minimizing the deterministic cost function defined for moving window with a finite number of samples at specific time interval. The optimal moving horizon observer was designed and implemented for the non-linear dynamic problem of aerial vehicle integrated navigation. The low grade commercial inertial measuring instrument (IMU) equipped with accelerometers and gyros sensors instrumented on-board in the strapdown configuration, is employed for collection of the real time experimental data. The data fusion algorithm of moving horizon estimation is realized and the results are collected from the offline algorithm testing on the Matlab software platform. Essential data processing and cleaning of data processing was conducted before algorithm application i.e. solving the multi rate sensors data synching and removing high frequency unwanted contents. Finally, the aerial vehicle dead reckoning integrated navigation was performed with recursive observer using IMU/GPS avionics. Contrary to the widely practiced extended Kalman filter results, recursive observer of MHE exhibited performance enhancement in the response and precision aspect, regardless of environmental noise and failure scenarios.

In order to understand swirl brakes mechanisms and their influence on rotordynamic characteristics for different types of seals, a three-dimensional flow numerical simulation was presented. Three typical seals including labyrinth seal, fully partitioned damper seal and hole-pattern seal were compared under three inlet conditions of no preswirl, preswirl and preswirl with swirl brakes. FAN boundary condition was used to provide inlet preswirl. A modified identification method of effective damping was proposed. Feasibility of the swirl brakes on improving performance of damper seals was discussed. The results show that the swirl brakes influence the seal stability characteristics with whirl frequency. For the labyrinth seal the swirl brakes reverse the sign of effective damping at low frequency and improve the seal stability performance in a wide frequency range. The swirl brakes also improve the damper seals' stability performance by increasing the low frequency effective damping and reducing their crossover frequency. Further results indicate the swirl brakes affect the rotational direction of the maximum (minimum) pressure positions and enhance the stability of the seals by reducing tangential force in each cavity.

The objective of this paper is to experimentally investigate and predict the mechanical behavior of polycarbonate over a wide range of strain rate from 10⁻⁴ to 5000 s⁻¹. Considering the influences of the glass (α) transition and the second (β) transition on the mechanical behavior of polycarbonate, a new constitutive model is proposed, and it is decomposed into the α and β components. The α component dominates the low and moderate rate deformations, and the β component is related to the high rate deformation. In comparison with the experimental results, the model can accurately predict the mechanical behavior of polycarbonate at low, moderate and high strain rates.

For difficulties in establishing complex coupling dynamics model of sugarcane-soil-wind system and the dynamic response process of sugarcane by wind effect is unknown problems, establishment of complex coupling dynamics model of sugarcane-soil-wind system was discovered. ALE (Arbitrary Lagrange-Euler) method and soil more hierarchical modeling technology were used in the model. And dynamic response process of sugarcane under wind load was analyzed. Result shows that the modeling method is feasible which can be used on the research of sugarcane lodging. Periodic decay reciprocating vibration occurs in the process.

The influence of temperature and strain rate on the 5A90-O had been researched by costant strain-rate tensile method. The result shows that, although 5A90-O is not an ideal superplastic material, under certain conditions, with a large extension rate, the maximum elongation is193.6%. The strain rate has a significant impact on the flow stress and tensile strength under T=375°C∼500°C. With the decrease of strain rate, the load is reduced. Another important factor that affects the flow stress of 5A90 is temperature. Under the same strain rate, the flow stress of 5A90 is lower with the temperature increase. We choose the Backofen law as the constitutive equation of 5A90, the best condition of 5A90 surperplastic deformation is T=400°C, ε = 0.005s⁻¹.

In the present study, numerical three dimensional model of trapezoidal cavity used in LFR was analysed. Results are presented in the form of Thermal losses occurring from the receiver operating with an absorber tube temperature from 350-550 K in step of 50 K and emissivity varied from 0.5-1.0. Effect of wind blowing below lower glass plate (cavity aperture) were also analysed considering the heat transfer coefficient from 5 to 25 W/m²K. At lower absorber temperature (350 K) convective losses is found to be 43% of the total heat loss whereas radiative losses accounted 57%. For higher absorber temperature radiative losses are dominant (77%) and convective losses are reduced to 23%. The air temperature gradient in the horizontal direction (parallel to lower glass plate) is found to be negligible whereas it is varied significantly in vertical direction (normal to lower glass plate). The average cavity air temperature is observed to be 480 K for low wind flow (h=5 W/m²K) and it reduces to 360 K for h=25 W/m²K. This has resulted in increased convective losses (27% higher).

Thoracic descending aorta diseases include aortic dissection and aortic aneurysm, of which the natural mortality rate is extremely high. At present, endovascular aneurysm repair (EVAR) has been widely used as an effective means for the treatment of descending aortic disease. Most of the existing coating stents are standard design, which are unable to meet the size or structure of different patients. As a result, failure of treatment would be caused by dimensional discrepancy between stent and vessels, which could lead to internal leakage or rupture of blood vessels. Therefore, based on rapid prototyping sacrificial core – coating forming (RPSC-CF), a customized aortic stent graft manufactured technique has been proposed in this study. The aortic stent graft consists of film and metallic stent, so polyether polyurethane (PU) and nickel-titanium (NiTi) shape memory alloy with good biocompatibility were chosen. To minimum film thickness without degrading performance, effect of different dip coating conditions on the thickness of film were studied. To make the NiTi alloy exhibit super-elasticity at body temperature (37°C), influence of different heat treatment conditions on austenite transformation temperature (Af) and mechanical properties were studied. The results show that the customized stent grafts could meet the demand of personalized therapy, and have good performance in blasting pressure and radial support force, laying the foundation for further animal experiment and clinical experiment.

Honeycomb structure infilling is an important way to achieve lightweight. Focusing on the deficiency of the non-optimized macro-material distribution in uniform honeycomb structures, a modeling method of non-uniform honeycomb structures based on topology optimization was proposed. The loaded component was topology-optimized and the density results were mapped to the relative density matrix of cells. The rapid and automatic modeling of non-uniform honeycomb structures was realized with the using of User-Defined Features and the cyclic definitions of the reference datums. The simulation results show that the mechanic performance of non-uniform honeycomb structures is better than uniform honeycomb structures and the efficiency of the proposed method is validated.

The finite element software ANSYS was adopted to simulate the temperature field distribution for laser cutting tempered glass, and the influence of different process parameters, including laser power, glass thickness and cutting speed, on temperature field distribution was studied in detail. The results show that the laser power has a greater influence on temperature field distribution than other paremeters, and when the laser power gets to 60W, the highest temperature reaches 749°C, which is higher than the glass softening temperature. It reflects the material near the laser spot is melted and the molten slag is removed by the high-energy water beam quickly. Finally, through the water guided laser cutting tempered glass experiment the FEM theoretical analysis was verified.

A novel designed piston-type synthetic jet actuator has been developed, which has a quick-return characteristic. When moving to the Top Dead Centre, the piston in high speed route moves faster than the classical one. Compared with classical piston-type SJA, the pressure ratio of the cavity, jet velocity and the jet momentum of the novel SJA increase significantly, which greatly enhances the performance of the actuator. A parametric study has been carried out focusing on the affection in different actuation frequencies and duty cycle. Results show that the performance of the quick-return piston-type SJA is significantly improved.

Rod fastening rotor (RFR) is the core part of gas turbine, the degradation of RFR has great effect on gas turbine's performance. One of the main reasons which cause the RFR performance degradation is creep damage, while few studies have been carried out in terms of it so far. In order to analyze the influence of preload on virtual material parameters, a dynamic model of RFR considering interface contact effect was built. Then equivalent stiffness of RFR and elements was analyzed as well. Furthermore, creep damage of elements under higher stress were analyzed with damage mechanics to get their influence on the total damage. Likewise, RFR were analyzed with damage mechanics to get the connection between the total damage and rupture life. The results showed that connection between the total damage and rupture life was a complicated, non-linear process. Moreover, the rods of turbine and combustion chamber were the biggest influencing factors. The results of this dissertation can be a support for structural design and life prediction of RFR.

In order to realize the automatic drilling in aircraft assembly, a drilling end effector is designed by integrating the pressure unit, drilling unit, measurement unit, control system and frame structure. In order to reduce the hole deviation, this paper proposes a vertical normal adjustment program based on 4 laser distance sensors. The actual normal direction of workpiece surface can be calculated through the sensors measurements, and then robot posture is adjusted to realize the hole deviation correction. A base detection method is proposed to detect and locate the hole automatically by using the camera and the reference hole. The experiment results show that the position accuracy of the system is less than 0.3mm, and the normal precision is less than 0.5°. The drilling end effector and robot can greatly improve the efficiency of the aircraft parts and assembly quality, and reduce the product development cycle.

Subtractive rapid prototyping is fast and automatic three dimensions physical modelling that uses computer aided design model as the input. The dimensional accuracy of the result of the subtractive rapid prototyping is influenced by its process parameters. The aim of this research is to study and then develop a model that shows the influence of depth of cut, feed rate, and step-over on the vertical length error, horizontal length error, and depth error in subtractive rapid prototyping of polycarbonate material. This research implements response surface methodology to develop the model and then followed by the residual tests to evaluate the developed model. The result shows that the increase of the feed rate and the step-over will increase the horizontal dimension error. The most influenced factor on the horizontal dimension error is the step-over. Meanwhile, the vertical dimension error will be affected mostly by the step-over. Last, the depth error is influenced by the feed rate, the step-over, and the depth of cut. The depth of cut is the most critical factor that increases the depth error. The developed models give an insight on how several process parameters of rapid prototyping will influence the dimensional accuracy of a polycarbonate material. Based on the model, efficient resources utilization can be achieved.

This paper presents a method for describing kinematic structure of bionic hand based on VF (virtual finger) set. At first, a 20 DOFs (degrees of freedom) human hand kinematic model is built, which is expressed by five fingers' kinematic chains consisting of kinematic pairs and symbols that represent geometric relationships of kinematic pairs' axes. Based on the concept of VF, the hand fingers are divided into two types: VF_AA having adduction/abduction motion and VF_FE having flexion/extension motion. The concept of VF set comprising VF_AAs and VF_FEs is defined, human hand and six basic grasp postures are described by VF set. Then, the structures corresponding VF_AA and VF_FE are given according to active and passive forms of finger joints, and VF_FE Structure-Base comprising 20 conventional structures is built. Based on VF set and the structures of VF_AA and VF_FE, VF sets and kinematic structures of several classic bionic hands are given.

The regenerative pump used in automotive is facing a noise problem. To understand the mechanism in detail, Computational Fluid Dynamics (CFD) and Computational Acoustic Analysis (CAA) together were used to understand the fluid and acoustic characteristics of the fuel pump using ANSYS-CFX 15.0 and LMS Virtual. Lab Rev12, respectively. The CFD model and acoustical model were validated by mass flow rate test and sound pressure test, respectively. Comparing the computational and experimental results shows that sound pressure levels at the observer position are consistent at high frequencies, especially at blade passing frequency. After validating the models, several numerical models were analyzed in the study for noise improvement. It is observed that for configuration having greater number of impeller blades, noise level was significantly improved at blade passing frequency, when compared to that of the original model.

Electrical discharge turning (EDT) is a new machining process in which an external axis is added to a conventional EDM machine in order to produce precise cylindrical forms on hard and difficult to machine materials. By feeding a pre shaped tool electrode against a rotating work piece, axially symmetrical pats can be produce. The machining performance of EDT process is influenced by its machining parameters, which directly affect the quality of the machined component. This paper presents an experimental study on the effects of EDM parameters namely pulse-on time, peak current, gap voltage, spindle speed and flushing pressure on material removal rate (MRR) in electrical discharge turning of titanium alloy Ti-6Al-4V. This has been done by means of the Taguchi's design of experiment technique. A mathematical model has been developed for MRR by regression analysis and factor effects were analyzed using analysis of variance (ANOVA). Signal-to-noise ratio analysis is used to find the optimal condition.

Thermal comfort and air quality within a car cabin are required during driving throughout various climates where energy is efficiently consumed to maintain acceptable conditions by air conditioning (AC) unit. This paper proposes an analysis of energy conversion within a car cabin for thermal comfort and air quality. Mathematical models, based on energy and mass balances, are developed to determine process variables of a car cabin. Experimental data from real conditions is compared with simulated results for model validation. There is very good agreement between those results. The proposed models are used to simulate interesting case studies in real circumstances for investigation on trade-off among thermal comfort, air quality, and energy usage.

Redundant design is one of the important methods to improve the reliability of the system, but mutual coupling of multiple factors is often involved in the design. In my study, Direct Search Method is introduced into the optimum redundancy configuration for design optimization, in which, the reliability, cost, structural weight and other factors can be taken into account simultaneously, and the redundant allocation and reliability design of aircraft critical system are computed. The results show that this method is convenient and workable, and applicable to the redundancy configurations and optimization of various designs upon appropriate modifications. And this method has a good practical value.

Current mechanical key in the motorcycle is prone to bulgary, being stolen or misplaced. Intelligent biometric voice recognition as means to replace this mechanism is proposed as an alternative. The proposed system will decide whether the voice is belong to the user or not and the word utter by the user is 'On' or 'Off'. The decision voice will be sent to Arduino in order to start or stop the engine. The recorded voice is processed in order to get some features which later be used as input to the proposed system. The Mel-Frequency Ceptral Coefficient (MFCC) is adopted as a feature extraction technique. The extracted feature is the used as input to the SVM-based identifier. Experimental results confirm the effectiveness of the proposed intelligent voice recognition and word recognition system. It show that the proposed method produces a good training and testing accuracy, 99.31% and 99.43%, respectively. Moreover, the proposed system shows the performance of false rejection rate (FRR) and false acceptance rate (FAR) accuracy of 0.18% and 17.58%, respectively. In the intelligent word recognition shows that the training and testing accuracy are 100% and 96.3%, respectively.

Vehicle weight is an important factor to be maintained for transportation safety. A weight limitation system is proposed to make sure the vehicle weight is always below its designation prior the vehicle is being used by the driver. The proposed system is divided into two systems, namely vehicle weight confirmation system and weight warning system. In vehicle weight confirmation system, the weight sensor work for the first time after the ignition switch is turned on. When the weight is under the weight limit, the starter engine can be switched on to start the engine system, otherwise it will be locked. The seconds system, will operated after checking all the door at close position, once the door of the car is closed, the weight warning system will check once again the weight during runing engine condition. The results of these two systems, vehicle weight confirmation system and weight warning system have 100 % accuracy, respectively. These show that the proposed vehicle weight limitation system operate well.

Considering the influence of sucker rod absorber (SRA) on longitudinal vibration of sucker rod string (SRS), a new model of mix sucker rod with absorber (MSRWA) in the form of numerical integration is built. In the detail, based on the dynamical theory of continuous systems, the wave equation of instantaneous motion of MSRWA is deduced. The dynamic response is solved out with the mode superposition method. The affecting factors of natural frequency are analyzed, such as the length, diameter, density and elastic modulus of SRS. Then three dimensional curves of natural frequency are obtained. The results are very important for the design and application of SRS.

Deflector is generally used as deflecting device of Vehicle-mounted Vertically Thermal Launched Missile. To study the features of three different kinds of deflectors, numerical simulation is used to simulate the jet flow around single-faced, double-faced, triple-faced deflector respectively in this dissertation. Pathlines, Mass flow rate through the observation surfaces built around the deflector, regions influenced by jet flow on ground are standards to be compared, characters of them can be concluded from an analysis.

Human-machine collaboration is becoming increasingly more necessary, and so collaborative robot applications are also in high demand. We selected a UR10 robot as our research subject for this study. First, we applied D-H coordinate transformation of the robot to establish a link system, and we then used inverse transformation to solve the robot's inverse kinematics and find all the joints. Use Lagrange method to analysis UR robot dynamics; use ADAMS multibody dynamics simulation software to dynamic simulation; verifying the correctness of the derived kinetic models.

In order to study the influence of the structural parameters of micro thruster applied in micro satellite attitude adjustment and orbital maneuver on its propulsion performance, this paper considers the factors influencing the performance of the thruster, and utilizes the orthogonal test design to obtain nine groups of micro-nozzles with different structural parameters. We processed this series of micro nozzles through MEMS (Micro-Electro-Mechanical Systems) technology. The micro-nozzles are made of single crystal silicon and glass through the anode bonding, and the electric heating wire is creatively processed through MEMS in the thrust chamber to improve the performance of the micro thruster. Experiments were carried out in a vacuum chamber. Finally, we analyse the experimental results by analysis of variance and analysis of range. The experimental results show that the performance of the micro nozzle is optimal when the semi-shrinking angle is 30 degrees, the semi-expansion angle is 15 degrees and the area ratio is 6.22. Meantime, the experiment verifies that it is feasible to improve the propulsive performance of micro-propulsion system through electronic heater strip.

Commonly termed as Hardware Trojans, is an emerging issue for global hardware security. The research on Hardware Trojan detection is urgent and significant. Dummy Scan Flip-Flop(DSFF) structure could be used to improve the probability of hardware Trojan activation, which is significant to hardware Trojan detection, especially during the design phase. In this express, an algorithm for inserting the DSFF structure based on driving vertex is proposed. According to the experimental results, under the same transition probability threshold(P_th), compared to the state-of-art, the proposed algorithm can reduce both the inserting complexity and the induced area overhead of the DSFF insertion. The maximum area optimization rate can reach 44.8%. The simulation results on S386 and S38584 benchmark circuits indicate that the proposed algorithm can significantly reduce Trojan authentication time by increasing activation probability of hardware Trojan circuits.

Aiming at the assistant decision-making system's bottleneck of processing the operational plan data and information, this paper starts from the analysis of the problem of traditional expression and the technical advantage of ontology, and then it defines the elements of the operational plan ontology model and determines the basis of construction. Later, it builds up a semi-knowledge-level operational plan ontology model. Finally, it probes into the operational plan expression based on the operational plan ontology model and the usage of the application software. Thus, this paper has the theoretical significance and application value in the improvement of interconnection and interoperability of the operational plan among assistant decision-making systems.