The paper describes the feasibility and method of the application of virtual reality technology to grinding process, and introduces the modeling method of object entity in the environment of virtual reality. The simul...The paper describes the feasibility and method of the application of virtual reality technology to grinding process, and introduces the modeling method of object entity in the environment of virtual reality. The simulation process of grinding wheels and ground surface roughness is discussed, and the computation program system of numerical simulation is compiled with Visual C++ programming language. At the same time, the three-dimensional simulation models of grinding wheels and ground surface roughness are made with OpenGL tool. The choice of grinding wheels, the forecast of ground surface quality and some simulation results can be realized by interactively inputting grinding parameters. The paper applies virtual reality technology to grinding process,makes the model of virtual grinding wheel and simulates the grinding process. The roughness of ground surface is showed in three-dimensional images, and therefore the grinding technology is studied. Computer simulation can not only be used as a shortcut to analyze and research the grinding process, but also increase the research scope and content. The virtual reality technology used in the paper is an advanced visualized simulation with interaction. The surface roughness Ra on simulated ground workpiece can be calculated by the arithmetic average of contour warp absolute value in sampling length of simulated ground workpiece. The parameters of virtual wheel and simulated grinding process can be changed by interaction input, so the simulated results in the desired grinding condition are gained. The effect of each parameter to ground surface can be analyzed by comparing the grinding results in different condition.展开更多
According to the characteristic of the echo of highfrequency ground wave radar(HF GWR), which is one-dimensional narrow band signal, a virtual direction of arrival(DOA) matrix is constructed at first, then the DOA...According to the characteristic of the echo of highfrequency ground wave radar(HF GWR), which is one-dimensional narrow band signal, a virtual direction of arrival(DOA) matrix is constructed at first, then the DOA of target evaluation is achieved by the method of resolving equations for two-dimensional DOA matrix. And this method bases on the redundancy information of a linear two-row array of antennae. Both the simulation process and the treatment results of measured data (in the case of low SNR echoes and short data series) are given at the end of this paper. By comparing with GPS data of the targets, the validity and practical applicability of the method in this paper is verified.展开更多
A self-organized integrated air-ground detection swarmis tentatively applied to achieve reentry vehicle landing detection,such as searching and rescuing a manned spaceship. The detectionswarm consists of multiple unma...A self-organized integrated air-ground detection swarmis tentatively applied to achieve reentry vehicle landing detection,such as searching and rescuing a manned spaceship. The detectionswarm consists of multiple unmanned aerial vehicles (UAVs)and unmanned ground vehicles (UGVs). The UAVs can accessa detected object quickly for high mobility, while the UGVs cancomprehensively investigate the object due to the variety of carriedequipment. In addition, the integrated air-ground detectionswarm is capable of detecting from the ground and the air simultaneously.To accomplish the coordination of the UGVs andUAVs, they are all regarded as individuals of the artificial swarm.Those individuals make control decisions independently of othersbased on the self-organizing strategy. The overall requirements forthe detection swarm are analyzed, and the theoretical model ofthe self-organizing strategy based on a combined individual andenvironmental virtual function is established. The numerical investigationproves that the self-organizing strategy is suitable andscalable to control the detection swarm. To further inspect the engineeringreliability, an experiment set is established in laboratory,and the experimental demonstration shows that the self-organizingstrategy drives the detection swarm forming a close range and multiangularsurveillance configuration of a landing spot.展开更多
文摘The paper describes the feasibility and method of the application of virtual reality technology to grinding process, and introduces the modeling method of object entity in the environment of virtual reality. The simulation process of grinding wheels and ground surface roughness is discussed, and the computation program system of numerical simulation is compiled with Visual C++ programming language. At the same time, the three-dimensional simulation models of grinding wheels and ground surface roughness are made with OpenGL tool. The choice of grinding wheels, the forecast of ground surface quality and some simulation results can be realized by interactively inputting grinding parameters. The paper applies virtual reality technology to grinding process,makes the model of virtual grinding wheel and simulates the grinding process. The roughness of ground surface is showed in three-dimensional images, and therefore the grinding technology is studied. Computer simulation can not only be used as a shortcut to analyze and research the grinding process, but also increase the research scope and content. The virtual reality technology used in the paper is an advanced visualized simulation with interaction. The surface roughness Ra on simulated ground workpiece can be calculated by the arithmetic average of contour warp absolute value in sampling length of simulated ground workpiece. The parameters of virtual wheel and simulated grinding process can be changed by interaction input, so the simulated results in the desired grinding condition are gained. The effect of each parameter to ground surface can be analyzed by comparing the grinding results in different condition.
基金Supported by the National High Technology and Devel-opment Program of China (2001AA631050)
文摘According to the characteristic of the echo of highfrequency ground wave radar(HF GWR), which is one-dimensional narrow band signal, a virtual direction of arrival(DOA) matrix is constructed at first, then the DOA of target evaluation is achieved by the method of resolving equations for two-dimensional DOA matrix. And this method bases on the redundancy information of a linear two-row array of antennae. Both the simulation process and the treatment results of measured data (in the case of low SNR echoes and short data series) are given at the end of this paper. By comparing with GPS data of the targets, the validity and practical applicability of the method in this paper is verified.
基金supported by the National Natural Science Foundation of China(11002076)the National High Technology Research and Development Program of China(863 Program)(2014AA7041002)
文摘A self-organized integrated air-ground detection swarmis tentatively applied to achieve reentry vehicle landing detection,such as searching and rescuing a manned spaceship. The detectionswarm consists of multiple unmanned aerial vehicles (UAVs)and unmanned ground vehicles (UGVs). The UAVs can accessa detected object quickly for high mobility, while the UGVs cancomprehensively investigate the object due to the variety of carriedequipment. In addition, the integrated air-ground detectionswarm is capable of detecting from the ground and the air simultaneously.To accomplish the coordination of the UGVs andUAVs, they are all regarded as individuals of the artificial swarm.Those individuals make control decisions independently of othersbased on the self-organizing strategy. The overall requirements forthe detection swarm are analyzed, and the theoretical model ofthe self-organizing strategy based on a combined individual andenvironmental virtual function is established. The numerical investigationproves that the self-organizing strategy is suitable andscalable to control the detection swarm. To further inspect the engineeringreliability, an experiment set is established in laboratory,and the experimental demonstration shows that the self-organizingstrategy drives the detection swarm forming a close range and multiangularsurveillance configuration of a landing spot.