Energy and environmental problems are more serious at present and people realized that the development of traditional engines is limited, and all countries in the world began studying all kinds of new piston engines. ...
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Energy and environmental problems are more serious at present and people realized that the development of traditional engines is limited, and all countries in the world began studying all kinds of new piston engines. In history, there have been various types of engine to replace the traditional ones. Of all these, the rotary piston engines are the most and most successful, including constant speed types, planetary types, and differential types. But they felled finally. With the development of science and technology, some problems seemingly hard to attack are resolved, new rotary engines, especially the differential type engine, are attracted more attentions gradually. Differential velocity engines are the focus of researchers for its characteristic of high power density, compact, smooth and capability of using various fuels. The technology of sealing, lubrication, and distribution used in traditional engines can also help to promote it.
Based on the fault feature locus with the change of the component parameters in node-voltage space, a fault diagnosis method based on AC iterative simulation before test is proposed. The slope fault model under AC sin...
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Based on the fault feature locus with the change of the component parameters in node-voltage space, a fault diagnosis method based on AC iterative simulation before test is proposed. The slope fault model under AC sinusoidal excitation is analyzed first, the idea of the AC iterative simulation before test and the fault diagnosis after test according to the parameter scanning simulation result is proposed;secondly, the procedure of the AC iterative simulation before test and fault diagnosis algorithm after test are both described. Furthermore, the test system of hardware and software for practical experiment is designed, mainly realized the signal acquisition and data analysis. The experiments of simulation and the practical circuit-board are implemented to validate the efficiency of the proposed method.
The accuracy of a micro inertial navigation system is greatly influenced by the complex vibration environment of the vehicle, an embedded vibration attenuation system structure is designedand its rigidity is checked. ...
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The accuracy of a micro inertial navigation system is greatly influenced by the complex vibration environment of the vehicle, an embedded vibration attenuation system structure is designedand its rigidity is checked. The correctness of this structure design is verified through the modal analysis and frequency response analysis using the finite element analysis software. Finally, based on the frequency response analysis, the model of damping system is carried out the random vibration response analysis, and an acceleration power spectral densitycurve of the structure under the vibration environment is obtained, which provides a reliable basis for the structure design.
Edge feature extraction has been a classic research in computer vision and image processing,and has been widely used in image *** this paper we propose a novel solution to edge extraction *** select first-order partia...
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Edge feature extraction has been a classic research in computer vision and image processing,and has been widely used in image *** this paper we propose a novel solution to edge extraction *** select first-order partial derivatives of two-dimensional Gaussian function as wavelet function,extract multi-scale image edge information by wavelet modulus maxima edge detection and the Half-Neighborhood Algorithm,and improve the traditional wavelet transformation *** performance of this algorithm meets the three edge detector indicators proposed by Canny,and the simulation results shows that this method has the better ***,it provides a basis for the further image matching.
The state graph contains state nodes and directed edges. The state nodes represent the events which will occur on the future battlefield. The directed edges depict the causality of the state nodes. An integrated appro...
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The state graph contains state nodes and directed edges. The state nodes represent the events which will occur on the future battlefield. The directed edges depict the causality of the state nodes. An integrated approach is developed to take use of the state graph to evaluate the situation of the battlefield. The situation assessment is to predict the probabilities of the future events' occurrence. Firstly, the Optimal Bayesian estimate and Dempster-Shafer(DS) evidence theory are exploited to fuse the information from the real-time battlefield. The fused information is used to update the current situation. Then, it helps commanders to predict the situation of the battlefield in the future by the method of Bayesian Network inference basis on the updated state graph. Finally, the experimental results demonstrate the effectiveness of the approach.
At the present, the principle between the key assembly parameters and performance of complex mechanical systems is not clear. In consideration of the situation that a large number of assembly process data has been sto...
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At the present, the principle between the key assembly parameters and performance of complex mechanical systems is not clear. In consideration of the situation that a large number of assembly process data has been stored in the manufacturing information system. Data Mining Technology(DM) is proposed to find the knowledge that may be hidden in the assembly data. Python is used as the data mining engine and its machine learning library Mlpy is used as algorithms library. By analyzing the actual assembly problems of servo mechanism, experimental data mining is designed and implemented by using PLS, K-means and SVM algorithms.
Silicon micro-fabricated gyroscope are very sensitive to ambient temperature, this paper conducted a novel active temperature controlling system. Combined with the PTC thermistor to detect internal temperature and the...
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In order to meet the logistics industry report management flexibility,maintainability and other requirements,based on Microsoft SQL Server 2008 R2 database and Spring MVC framework of logistics report system design,co...
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ISBN:
(纸本)9781510806528
In order to meet the logistics industry report management flexibility,maintainability and other requirements,based on Microsoft SQL Server 2008 R2 database and Spring MVC framework of logistics report system design,combined with concrete practice process of the research and development of specific system architecture and the specific function of each module requirements,gives the detailed design and implementation process.
The variable spring-loaded inverted pendulum (V-SLIP) model captures characteristic properties of the hip or COM motion in human locomotion. A control strategy consists of a leg stiffness controller and a foot placeme...
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ISBN:
(纸本)9781467375245
The variable spring-loaded inverted pendulum (V-SLIP) model captures characteristic properties of the hip or COM motion in human locomotion. A control strategy consists of a leg stiffness controller and a foot placement controller is proposed for a biped walker. Some restrictions are considered in the control strategy, e.g. the friction and the ability of the actuator. A novel trajectory function is designed for stance phase control. The function not only can approximate the nominal trajectory with error in the order of sub-millimeter, but also can preserve the restriction on vertical velocity in spite of the horizontal velocity. To validate the control strategy and the trajectory function, simulations are implemented on a virtual ideal biped walker. The walker starts walking with a low velocity, by taking a few steps it comes to the desired walking cycle. With the proposed control strategy the walker is able to recover from a disturbance up to 20 N*m.
This paper presents an online motion planning method based on Continuation/Generalized Minimum Residual (C/GMRES) to solve a receding horizon optimization problem for unmanned aerial vehicles (UAVs). Hard constraints,...
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This paper presents an online motion planning method based on Continuation/Generalized Minimum Residual (C/GMRES) to solve a receding horizon optimization problem for unmanned aerial vehicles (UAVs). Hard constraints, such as nonlinear state, input saturation constraints and obstacle constraint are included into the problem formulation by introducing the dummy factors. The optimal control problem model of motion planning for UAVs in Bolza form is constructed and the necessary optimality conditions are derived based on the Lagrange Multipliers method. The singularity that method may exist is avoided by adding a small penalty to the Lagrange function. Compared with conventional iterative methods, the proposed method requires much less computational burden, since the linear equation is solved only once at each sampling time and the product of a matrix and a vector is replaced with forward difference approximation, then GMRES is used to rapidly solve a large linear equation. Finally, the proposed method is applied to motion planning problem for a fixed-wing UAV in both obstacle-free and obstacle environment. Simulation results show that the method can generate a feasible trajectory from initial position to destination while satisfying all constraints and the real-time performance.
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