In the bearings-only target tracking, wireless sensor network （WSN） collects observations of the target direction at various nodes and uses an adaptive filter to combine them for target tracking. An efficient networ...In the bearings-only target tracking, wireless sensor network （WSN） collects observations of the target direction at various nodes and uses an adaptive filter to combine them for target tracking. An efficient network management is necessary to gain an optimal tradeoffbetween locating accuracy and energy consumption. This article proposes a self-organizing target tracking algorithm to select the most beneficial subset of nodes to track the target at every snapshot. Compared with traditional methods, this scheme avoids the need for keeping global position information of the network as in greedy selection. Each node judges its future usefulness depending on the knowledge of its own position and using simple mathematics computation. Simulations indicate that this scheme has locating accuracy comparable to the global greedy algorithm. Also, it has good robustness against node failure and autonomous adaptability to the change of the network scale. Furthermore, this algorithm consumes limited energy because only a portion of nodes partakes in the selection at every snapshot.展开更多
This paper presents a study on bioinspired closed-loop Central Pattern Generator(CPG)based control of a robot fish for obstacle avoidance and direction tracking.The biomimetic robot fish is made of a rigid head with a...This paper presents a study on bioinspired closed-loop Central Pattern Generator(CPG)based control of a robot fish for obstacle avoidance and direction tracking.The biomimetic robot fish is made of a rigid head with a pair of pectoral fins,a wire-driven active body covered with soft skin,and a compliant tail.The CPG model consists of four input parameters:the flapping amplitude,the flapping angular velocity,the flapping offset,and the time ratio between the beat phase and the restore phase in flapping.The robot fish is equipped with three infrared sensors mounted on the left,front and right of the robot fish,as well as an inertial measurement unit,from which the surrounding obstacles and moving direction can be sensed.Based on these sensor signals,the closed-loop CPG-based control can drive the robot fish to avoid obstacles and to track designated directions.Four sets of experiments are presented,including avoiding a static obstacle,avoiding a moving obstacle,tracking a designated direction and tracking a designated direction with an obstacle in the path.The experiment results indicated that the presented control strategy worked well and the robot fish can accomplish the obstacle avoidance and direction tracking effectively.展开更多
针对在Virtools Dev 3.5平台下实现漫游地图的各种功能存在实现算法不完善等问题,给出漫游者前进方向实时显示、漫游者位置实时显示、漫游地图的缩放和跳转等功能的实现方法,并制作出3个自成体系的通用模块.在用Virtools制作类似漫游的...针对在Virtools Dev 3.5平台下实现漫游地图的各种功能存在实现算法不完善等问题,给出漫游者前进方向实时显示、漫游者位置实时显示、漫游地图的缩放和跳转等功能的实现方法,并制作出3个自成体系的通用模块.在用Virtools制作类似漫游的应用中,可以使用这3个通用模块快速实现漫游地图的4种功能,提高了开发效率.在漫游者位置实时显示功能算法中使用双重定位策略和地图缩放策略,保证了整个定位显示画面的准确性和流畅性.展开更多
A sequential processing is presented aiming at optimizing the direction of arrival(DOA)tracking performance.Firstly,current positions and Doppler frequency are estimated and a mathematical model is derived in order to...A sequential processing is presented aiming at optimizing the direction of arrival(DOA)tracking performance.Firstly,current positions and Doppler frequency are estimated and a mathematical model is derived in order to clarify the effect of Doppler frequency on the estimation.The Doppler effect is employed within subspace concept in order to refine the estimation of the target position.Secondly,a renewed weight factor that depends on target maneuver is employed in order to realize more accurate association and smoothing processes.Simulation results show that the presented method has high accuracy in DOA tracking.展开更多
Tracking moving wideband sound sources is one of the most challenging issues in the acoustic array signal processing which is based on the direction of arrival(DOA) estimation. Compressive sensing(CS) is a recent theo...Tracking moving wideband sound sources is one of the most challenging issues in the acoustic array signal processing which is based on the direction of arrival(DOA) estimation. Compressive sensing(CS) is a recent theory exploring the signal sparsity representation, which has been proved to be superior for the DOA estimation. However, the spatial aliasing and the offset at endfire are the main obstacles for CS applied in the wideband DOA estimation. We propose a particle filter based compressive sensing method for tracking moving wideband sound sources. First, the initial DOA estimates are obtained by wideband CS algorithms. Then, the real sources are approximated by a set of particles with different weights assigned. The kernel density estimator is used as the likelihood function of particle filter. We present the results for both uniform and random linear array. Simulation results show that the spatial aliasing is disappeared and the offset at endfire is reduced. We show that the proposed method can achieve satisfactory tracking performance regardless of using uniform or random linear array.展开更多
The problem of direction-of-arrival (DOA) estimation in mobile communication systems requires efficient algorithms with a high spatial resolution and a low computational complexity when moving sources are considered. ...The problem of direction-of-arrival (DOA) estimation in mobile communication systems requires efficient algorithms with a high spatial resolution and a low computational complexity when moving sources are considered. MUSIC is known as a high resolution algorithm for DOA estimation but, this method demands high computational complexity to compute the signal subspace of the time-varying data of the correlation matrix. This paper focuses on MUSIC using subspace tracking methods, such as Bi-SVD and PAST, to carry out iterative DOA estimation. Accuracy and the processing time of both methods are evaluated and compared with the results of MUSIC. These results show the potential of Bi-SVD and PAST to reduce the processing time and to improve the accuracy when the number of snapshots and the source angular variation increases, assessing the source location for a dynamic mobile cellular environment.展开更多
基金National Natural Science Foundation of China （60532030） National Science Fund for Distinguished Young Scholars （60625102） Ph.D. Programs Foundation of Ministry of Education of China （200802240）
文摘In the bearings-only target tracking, wireless sensor network （WSN） collects observations of the target direction at various nodes and uses an adaptive filter to combine them for target tracking. An efficient network management is necessary to gain an optimal tradeoffbetween locating accuracy and energy consumption. This article proposes a self-organizing target tracking algorithm to select the most beneficial subset of nodes to track the target at every snapshot. Compared with traditional methods, this scheme avoids the need for keeping global position information of the network as in greedy selection. Each node judges its future usefulness depending on the knowledge of its own position and using simple mathematics computation. Simulations indicate that this scheme has locating accuracy comparable to the global greedy algorithm. Also, it has good robustness against node failure and autonomous adaptability to the change of the network scale. Furthermore, this algorithm consumes limited energy because only a portion of nodes partakes in the selection at every snapshot.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(class A)(Grant No.XDA22040203)the Fundamental Research Funds for the Central Universities(Grant No.2019XX01)+1 种基金GDNRC[2020]031the Natural Science Foundation of Guangdong Province(Grant No.2020A1515010621).
文摘This paper presents a study on bioinspired closed-loop Central Pattern Generator(CPG)based control of a robot fish for obstacle avoidance and direction tracking.The biomimetic robot fish is made of a rigid head with a pair of pectoral fins,a wire-driven active body covered with soft skin,and a compliant tail.The CPG model consists of four input parameters:the flapping amplitude,the flapping angular velocity,the flapping offset,and the time ratio between the beat phase and the restore phase in flapping.The robot fish is equipped with three infrared sensors mounted on the left,front and right of the robot fish,as well as an inertial measurement unit,from which the surrounding obstacles and moving direction can be sensed.Based on these sensor signals,the closed-loop CPG-based control can drive the robot fish to avoid obstacles and to track designated directions.Four sets of experiments are presented,including avoiding a static obstacle,avoiding a moving obstacle,tracking a designated direction and tracking a designated direction with an obstacle in the path.The experiment results indicated that the presented control strategy worked well and the robot fish can accomplish the obstacle avoidance and direction tracking effectively.
文摘针对在Virtools Dev 3.5平台下实现漫游地图的各种功能存在实现算法不完善等问题,给出漫游者前进方向实时显示、漫游者位置实时显示、漫游地图的缩放和跳转等功能的实现方法,并制作出3个自成体系的通用模块.在用Virtools制作类似漫游的应用中,可以使用这3个通用模块快速实现漫游地图的4种功能,提高了开发效率.在漫游者位置实时显示功能算法中使用双重定位策略和地图缩放策略,保证了整个定位显示画面的准确性和流畅性.
文摘A sequential processing is presented aiming at optimizing the direction of arrival(DOA)tracking performance.Firstly,current positions and Doppler frequency are estimated and a mathematical model is derived in order to clarify the effect of Doppler frequency on the estimation.The Doppler effect is employed within subspace concept in order to refine the estimation of the target position.Secondly,a renewed weight factor that depends on target maneuver is employed in order to realize more accurate association and smoothing processes.Simulation results show that the presented method has high accuracy in DOA tracking.
基金supported by the NFSC Grants 51375385 and 51675425Natural Science Basic Research Plan in Shaanxi Province of China Grants 2016JZ013
文摘Tracking moving wideband sound sources is one of the most challenging issues in the acoustic array signal processing which is based on the direction of arrival(DOA) estimation. Compressive sensing(CS) is a recent theory exploring the signal sparsity representation, which has been proved to be superior for the DOA estimation. However, the spatial aliasing and the offset at endfire are the main obstacles for CS applied in the wideband DOA estimation. We propose a particle filter based compressive sensing method for tracking moving wideband sound sources. First, the initial DOA estimates are obtained by wideband CS algorithms. Then, the real sources are approximated by a set of particles with different weights assigned. The kernel density estimator is used as the likelihood function of particle filter. We present the results for both uniform and random linear array. Simulation results show that the spatial aliasing is disappeared and the offset at endfire is reduced. We show that the proposed method can achieve satisfactory tracking performance regardless of using uniform or random linear array.
文摘The problem of direction-of-arrival (DOA) estimation in mobile communication systems requires efficient algorithms with a high spatial resolution and a low computational complexity when moving sources are considered. MUSIC is known as a high resolution algorithm for DOA estimation but, this method demands high computational complexity to compute the signal subspace of the time-varying data of the correlation matrix. This paper focuses on MUSIC using subspace tracking methods, such as Bi-SVD and PAST, to carry out iterative DOA estimation. Accuracy and the processing time of both methods are evaluated and compared with the results of MUSIC. These results show the potential of Bi-SVD and PAST to reduce the processing time and to improve the accuracy when the number of snapshots and the source angular variation increases, assessing the source location for a dynamic mobile cellular environment.
