To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm i...To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm is introduced.Firstly,a formation controller based on prescribed performance theory is designed to control the transient and steady formation configuration,as well as the formation forming time,which not only can form the designated formation configuration but also can guarantee collision avoidance and terrain avoidance theoretically.Next,considering the constraints caused by formation controller on trajectory planning such as the safe distance,turn angle and step length,as well as the constraint of formation shape,a leader trajectory planning method based on sparse A^(*)algorithm is proposed.Simulation results show that the UAV formation can arrive at the destination safely with a short trajectory no matter keeping the formation or encountering formation transformation.展开更多
Multiple UAVs are usually deployed to provide robustness through redundancy and to accomplish surveillance,search,attack and rescue missions.Formation reconfiguration was inevitable during the flight when the mission ...Multiple UAVs are usually deployed to provide robustness through redundancy and to accomplish surveillance,search,attack and rescue missions.Formation reconfiguration was inevitable during the flight when the mission was adjusted or the environment varied.Taking the typical formation reconfiguration from a triangular penetrating formation to a circular tracking formation for example,a path planning method based on Dubins trajectory and particle swarm optimization(PSO)algorithm is presented in this paper.The mathematic model of multiple UAVs formation reconfiguration was built firstly.According to the kinematic model of aerial vehicles,a process of dimensionality reduction was carried out to simplify the model based on Dubins trajectory.The PSO algorithm was adopted to resolve the optimization problem of formation reconfiguration path planning.Finally,the simulation and vehicles flight experiment are executed.Results show that the path planning method based on the Dubins trajectory and the PSO algorithm can generate feasible paths for vehicles on time,to guarantee the rapidity and effectiveness of formation reconfigurations.Furthermore,from the simulation results,the method is universal and could be extended easily to the path planning problem for different kinds of formation reconfigurations.展开更多
The paper consists of three topics on control theory and engineering applications, namely bifurcation control, manufacturing planning, and formation control. For each topic, we summarize the control problem to be addr...The paper consists of three topics on control theory and engineering applications, namely bifurcation control, manufacturing planning, and formation control. For each topic, we summarize the control problem to be addressed and some key ideas used in our recent research. Interested readers are referred to related publications for more details. Each of the three topics in this paper is technically independent from the other ones. However, all three parts together reflect the recent research activities of the first author, jointly with other researchers in different fields.展开更多
Path planning and formation structure forming are two of the most important problems for autonomous underwater vehicles(AUVs) to collaborate with each other.In this work,a dynamic formation model was proposed,in which...Path planning and formation structure forming are two of the most important problems for autonomous underwater vehicles(AUVs) to collaborate with each other.In this work,a dynamic formation model was proposed,in which several algorithms were developed for the complex underwater environment.Dimension changeable particle swarm algorithm was used to find an optimized path by dynamically adjusting the number and the distribution of the path nodes.Position relationship based obstacle avoidance algorithm was designed to detour along the edges of obstacles.Virtual potential point based formation-keeping algorithm was employed by incorporating dynamic strategies which were decided by the current states of the formation.The virtual potential point was used to keep the formation structure when the AUV or the formation was deviated.Simulation results show that an optimal path can be dynamically planned with fewer path nodes and smaller fitness,even with a concave obstacle.It has been also proven that different formation-keeping strategies can be adaptively selected and the formation can change its structure in a narrow area and restore back after passing the obstacle.展开更多
Creative regions and their formation in a region depend on several factors. These factors are effective when placed side by side and have a positive impact on the establishment of the physical system of area. In fact,...Creative regions and their formation in a region depend on several factors. These factors are effective when placed side by side and have a positive impact on the establishment of the physical system of area. In fact, continuous and chained activity of these factors will play an important map. The connection between the key factors of creative region is named creative ecosystem that starts from a point, and after a few steps becomes a creative idea. Finding this ecosystem is particularly important in formation of the creative region. With proper understanding, apropos analysis, and timely use of this chain, actual and virtual potentials of region will be stimulated and pleasant result will come out. This paper explores the creative region factors and components that can be involved in the creative ecosystem. These factors are sometimes fundamental and sometimes minor considered compared to the current situation in the region. The used research method is grounded theory and in fundamental extent, it is seeking to achieve an underlying or grounded theory. After investigations and the results of this study, a creative region cycle theory has been reached and is presented as a fundamental theory that is a basis for formation of future researches. In the cycle of creative region, innovation, social capital, creative human capital and living quality are discussed that as the criteria for the formation of a creative region have numerous separated indicators.展开更多
针对多目标突防组网雷达系统场景,为有效提高干扰效果以及突防成功率,编队航迹规划尤为重要。因此,首先构建航迹规划模型,从飞行器自身约束、航迹安全性、机间协调以及任务完成效果4个方面出发,结合多机伴随式编队及其所处环境特点,提...针对多目标突防组网雷达系统场景,为有效提高干扰效果以及突防成功率,编队航迹规划尤为重要。因此,首先构建航迹规划模型,从飞行器自身约束、航迹安全性、机间协调以及任务完成效果4个方面出发,结合多机伴随式编队及其所处环境特点,提出较为完备的航迹规划准则,形成一个新的整体目标函数;其次,为有效描述每架飞机的机动特性以及伴飞干扰机与目标飞机间的联系,提高算法搜索能力,提出基于多球面矢量(multi-spherical vector-based,MS)方法;为进一步提高算法的探索和开发能力,提出多面球矢量逐航迹点学习混合粒子群优化(multi-spherical vector-based hybrid particle swarm optimization with track point by track point learning,TLHPSO)算法,并将两者相结合,形成基于多面球矢量的逐航迹点学习混合粒子群优化(MS-based hybrid particle swarm optimization with track point by track point learning,MS-TLHPSO)航迹规划方法;最后,构建相应仿真场景进行验证。对比结果表明,MS方法以及TLHPSO优化算法在寻优能力上具有明显优势;同时,所提算法在不同初始场景下最优解的平均值均优于其他算法,充分说明所提算法能够在保证稳定性的前提下规划具有更高可信度的编队航迹。展开更多
基金supported by the National Natural Science Foundation of China(11502019).
文摘To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm is introduced.Firstly,a formation controller based on prescribed performance theory is designed to control the transient and steady formation configuration,as well as the formation forming time,which not only can form the designated formation configuration but also can guarantee collision avoidance and terrain avoidance theoretically.Next,considering the constraints caused by formation controller on trajectory planning such as the safe distance,turn angle and step length,as well as the constraint of formation shape,a leader trajectory planning method based on sparse A^(*)algorithm is proposed.Simulation results show that the UAV formation can arrive at the destination safely with a short trajectory no matter keeping the formation or encountering formation transformation.
基金Project (61703414) supported by the National Natural Science Foundation of ChinaProject (3101047) supported by the Defense Science and Technology Foundation of China+1 种基金Project (2017JJ3366) supported by the Natural Science Foundation of Hunan ChinaProject (2015M582881) supported by the China Postdoctoral Science Foundation
文摘Multiple UAVs are usually deployed to provide robustness through redundancy and to accomplish surveillance,search,attack and rescue missions.Formation reconfiguration was inevitable during the flight when the mission was adjusted or the environment varied.Taking the typical formation reconfiguration from a triangular penetrating formation to a circular tracking formation for example,a path planning method based on Dubins trajectory and particle swarm optimization(PSO)algorithm is presented in this paper.The mathematic model of multiple UAVs formation reconfiguration was built firstly.According to the kinematic model of aerial vehicles,a process of dimensionality reduction was carried out to simplify the model based on Dubins trajectory.The PSO algorithm was adopted to resolve the optimization problem of formation reconfiguration path planning.Finally,the simulation and vehicles flight experiment are executed.Results show that the path planning method based on the Dubins trajectory and the PSO algorithm can generate feasible paths for vehicles on time,to guarantee the rapidity and effectiveness of formation reconfigurations.Furthermore,from the simulation results,the method is universal and could be extended easily to the path planning problem for different kinds of formation reconfigurations.
基金Supported in part by Ford Motor Company, U.S. Air Force Research Laboratory, and National Science Foundation
文摘The paper consists of three topics on control theory and engineering applications, namely bifurcation control, manufacturing planning, and formation control. For each topic, we summarize the control problem to be addressed and some key ideas used in our recent research. Interested readers are referred to related publications for more details. Each of the three topics in this paper is technically independent from the other ones. However, all three parts together reflect the recent research activities of the first author, jointly with other researchers in different fields.
基金Project(NS2013091)supported by the Basis Research Fund of Nanjing University of Aeronautics and Astronautics,China
文摘Path planning and formation structure forming are two of the most important problems for autonomous underwater vehicles(AUVs) to collaborate with each other.In this work,a dynamic formation model was proposed,in which several algorithms were developed for the complex underwater environment.Dimension changeable particle swarm algorithm was used to find an optimized path by dynamically adjusting the number and the distribution of the path nodes.Position relationship based obstacle avoidance algorithm was designed to detour along the edges of obstacles.Virtual potential point based formation-keeping algorithm was employed by incorporating dynamic strategies which were decided by the current states of the formation.The virtual potential point was used to keep the formation structure when the AUV or the formation was deviated.Simulation results show that an optimal path can be dynamically planned with fewer path nodes and smaller fitness,even with a concave obstacle.It has been also proven that different formation-keeping strategies can be adaptively selected and the formation can change its structure in a narrow area and restore back after passing the obstacle.
文摘Creative regions and their formation in a region depend on several factors. These factors are effective when placed side by side and have a positive impact on the establishment of the physical system of area. In fact, continuous and chained activity of these factors will play an important map. The connection between the key factors of creative region is named creative ecosystem that starts from a point, and after a few steps becomes a creative idea. Finding this ecosystem is particularly important in formation of the creative region. With proper understanding, apropos analysis, and timely use of this chain, actual and virtual potentials of region will be stimulated and pleasant result will come out. This paper explores the creative region factors and components that can be involved in the creative ecosystem. These factors are sometimes fundamental and sometimes minor considered compared to the current situation in the region. The used research method is grounded theory and in fundamental extent, it is seeking to achieve an underlying or grounded theory. After investigations and the results of this study, a creative region cycle theory has been reached and is presented as a fundamental theory that is a basis for formation of future researches. In the cycle of creative region, innovation, social capital, creative human capital and living quality are discussed that as the criteria for the formation of a creative region have numerous separated indicators.
文摘针对多目标突防组网雷达系统场景,为有效提高干扰效果以及突防成功率,编队航迹规划尤为重要。因此,首先构建航迹规划模型,从飞行器自身约束、航迹安全性、机间协调以及任务完成效果4个方面出发,结合多机伴随式编队及其所处环境特点,提出较为完备的航迹规划准则,形成一个新的整体目标函数;其次,为有效描述每架飞机的机动特性以及伴飞干扰机与目标飞机间的联系,提高算法搜索能力,提出基于多球面矢量(multi-spherical vector-based,MS)方法;为进一步提高算法的探索和开发能力,提出多面球矢量逐航迹点学习混合粒子群优化(multi-spherical vector-based hybrid particle swarm optimization with track point by track point learning,TLHPSO)算法,并将两者相结合,形成基于多面球矢量的逐航迹点学习混合粒子群优化(MS-based hybrid particle swarm optimization with track point by track point learning,MS-TLHPSO)航迹规划方法;最后,构建相应仿真场景进行验证。对比结果表明,MS方法以及TLHPSO优化算法在寻优能力上具有明显优势;同时,所提算法在不同初始场景下最优解的平均值均优于其他算法,充分说明所提算法能够在保证稳定性的前提下规划具有更高可信度的编队航迹。
