In this paper an Ad hoc networks are established for the communication among unmanned air vehicle (UAV) group corporation. It is brought out that reference point group mobility model (RPGM) could simulate the behavior...
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In this paper an Ad hoc networks are established for the communication among unmanned air vehicle (UAV) group corporation. It is brought out that reference point group mobility model (RPGM) could simulate the behavior of UAV group to analyze the efficiency of router algorithms as to the movement of UAV node. The result shows that the Ad hoc networks can solve the communication problem of UAV group, and also find out that the ADOV algorithm has data large throughout and more adaptive to the variation of topology, the DSR has a lighter routing load. The efficiency of router algorithm also changes as to the node speed. As a result the routing algorithm should be chosen according to the different tactical mission of UAV group, and the designs of corporation method should consider the changing of network efficiency as to node moving speed.
In order to describe precisely the dynamics and friction nonlinearity of servo systems, a novel direct identification method for nonlinear continuous model is proposed. The sampled input-output data and logic data cor...
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In order to describe precisely the dynamics and friction nonlinearity of servo systems, a novel direct identification method for nonlinear continuous model is proposed. The sampled input-output data and logic data corresponding to the velocity direction are chosen as the identification data. Through equivalent transformation, the unknown parameters are removed to the linear part of the model. Then the identification method based on state variable filter is utilized to determine the unknown parameters. Subsequently, the nonlinear continuous model of the servo system is obtained. The effectiveness of the proposed method is demonstrated by simulations and identification experiments on the two axis servo table. Both the simulations and experimental results show that, with the proposed method, the accurate nonlinear continuous model can be obtained even under sensor noises, which gives an accurate description of the system dynamics.
Compressive sensing is a revolutionary idea proposed recently to achieve much lower sampling rate for signals. In the image application with limited resources the camera data can be stored and processed in compressed ...
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Compressive sensing is a revolutionary idea proposed recently to achieve much lower sampling rate for signals. In the image application with limited resources the camera data can be stored and processed in compressed form. An algorithm for moving object and region detection in video using a compressive sampling is developed. The algorithm estimates motion information of the moving object and regions in the video from the compressive measurements of the current image and background *** algorithm does not perform inverse compressive operation to obtain the actual pixels of the current image nor the estimated background. This leads to a computationally efficient method and a system compared with the existing motion estimation *** experimental results show that the sampling rate can reduce to 25% without sacrificing performance.
The dynamic weapon-target assignment (DWTA) problem is an important issue in the field of military command and control. An asset-based DWTA optimization model was proposed with four kinds of constraints considered, ...
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The dynamic weapon-target assignment (DWTA) problem is an important issue in the field of military command and control. An asset-based DWTA optimization model was proposed with four kinds of constraints considered, including capability constraints, strategy constraints, resource constraints and engagement feasibility constraints. A general "virtual" representation of decisions was presented to facilitate the generation of feasible decisions. The representation is in essence the permutation of all assignment pairs. A construction procedure converts the permutations into real feasible decisions. In order to solve this problem, three evolutionary decision-making algorithms, including a genetic algorithm and two memetic algorithms, were developed. Experimental results show that the memetic algorithm based on greedy local search can generate obviously better DWTA decisions, especially for large-scale problems, than the genetic algorithm and the memetic algorithm based on steepest local search.
This brief paper reports a hybrid algorithm we developed recently to solve the global optimization problems of multimodal functions, by combining the advantages of two powerful population-based metaheuristics differen...
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This brief paper reports a hybrid algorithm we developed recently to solve the global optimization problems of multimodal functions, by combining the advantages of two powerful population-based metaheuristics differential evolution (DE) and particle swarm optimization (PSO). In the hybrid denoted by DEPSO, each individual in one generation chooses its evolution method, DE or PSO, in a statistical learning way. The choice depends on the relative success ratio of the two methods in a previous learning period. The proposed DEPSO is compared with its PSO and DE parents, two advanced DE variants one of which is suggested by the originators of DE, two advanced PSO variants one of which is acknowledged as a recent standard by PSO community, and also a previous DEPSO. Benchmark tests demonstrate that the DEPSO is more competent for the global optimization of multimodal functions due to its high optimization quality.
Complete coverage path planning is a key problem for autonomous mobile robot, which concerns both efficiency and completeness of coverage. This paper proposed a novel strategy of combined coverage path planning method...
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In this paper the problem of path following control of autonomous vehicles subject to sliding is addressed. First a kinematic model is built which takes sliding effects into account by introducing two additional tire ...
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Regulators are important components in pneumatic system, and their flow-rate characteristics are the key parameters for designers. According to the correlatively international standard and national standard of China, ...
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Regulators are important components in pneumatic system, and their flow-rate characteristics are the key parameters for designers. According to the correlatively international standard and national standard of China, which describe the flow-rate characteristics measurement method of pneumatic regulators, the pressure and the flow are measured point by point, and then the flow-rate characteristics curve is plotted point to point. This method has some disadvantages, such as equipment complexity, much air consumption, and low efficiency. To settle the problems presented above, this paper puts forward a new high efficient and energy saving flow-rate characteristics measurement method of regulators, which is based on the pressure response when charging and discharging to an isothermal tank without any flow meters. The measurement principle, the system and the steps are introduced. And the tracking differentiator is used for the data processing of the pressure difference. Two typical kinds of regulators were experimentally investigated, and their flow-rate characteristics curves were obtained with the new and the conventional method, respectively. Comparatively, it's proved that this new method is feasible because it is not only able to meet the demand of the measurement precision, but also to save energy and improve efficiency. Compared to the conventional method, the new method takes only about 1/10 amount of time and consumes about only 1/30 amount of air. Hopefully it will be able to serve as an international standard of flow-rate characteristics measurement method of regulators.
The CCD pixels nonuniformity may give a greater margin of error to measurement results in the high-precision CCD measurement and servo control *** paper analyzes the image pixels nonuniformity caused by noises,and est...
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The CCD pixels nonuniformity may give a greater margin of error to measurement results in the high-precision CCD measurement and servo control *** paper analyzes the image pixels nonuniformity caused by noises,and establishes the corresponding image *** threshold value segmentation algorithm is used for image *** algorithm using two point linear method for pixel nonuniformity correction,getting center coordinates of facula by calculating the zeroth order moment and first moment of image is put forward,and a new image calibrated method that transforms the image coordinates into the real is *** results show that the algorithm can separate light intensity parts from the image,correct pixel nonuniformity,and stabilize pixel gray value of light intensity *** will make the center coordinates of image light intensity spots stable and decrease the error of the real coordinates after conversion,if the images are acquired under the same *** measurement precision as well as the control precision is improved greatly.
This paper deals with the H control of spatially interconnected systems where homogeneous subsystems communicate with their neighbors over packet dropping *** the robust stability analysis and controller synthesis pro...
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This paper deals with the H control of spatially interconnected systems where homogeneous subsystems communicate with their neighbors over packet dropping *** the robust stability analysis and controller synthesis problems are thoroughly *** first, temporal forward and spatial shift operators are used to model the interconnected systems with random communication packet losses as discrete time-space linear multidimensional systems with Markovian jumping *** conditions are obtained which make the whole interconnected systems mean-square stable and achieve the prescribed H disturbance attenuation *** method for designing distributed state feedback controllers are presented, which could robustly mean-square stabilize the interconnected *** results take the form of computationally tractable linear matrix ***, a simulation example of multiple vehicle platoon control with the effect of communication packet losses is exploited to demonstrate the effectiveness of the proposed model and method.
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