This paper conducts a series of case studies on a novel Simultaneous Path and Motion Planning (SiPaMoP) approach [1] to multiple autonomous or Automated Guided Vehicle (AGV) motion coordination in bidirectional networ...This paper conducts a series of case studies on a novel Simultaneous Path and Motion Planning (SiPaMoP) approach [1] to multiple autonomous or Automated Guided Vehicle (AGV) motion coordination in bidirectional networks. The SiPaMoP approach plans collision-free paths for vehicles based on the principle of shortest path by dynamically changing the vehicles’ paths,traveling speeds or waiting times,whichever gives the shortest traveling time. It integrates path planning,collision avoidance and motion planning into a comprehensive model and optimizes the vehicles’ path and motion to minimize the completion time of a set of tasks. Five case studies,i.e.,head-on collision avoidance,catching-up collision avoidance,buffer node generation and collision avoidance,prioritybased motion coordination,and safety distance based planning,are presented. The results demonstrated that the method can effectively plan the path and motion for a team of autonomous vehicles or AGVs,and solve the problems of traffic congestion and collision under various conditions.展开更多
It is a striking fact that the path tracking accuracy of autonomous vehicles based on active front wheel steering is poor under high-speed and large-curvature conditions.In this study,an adaptive path tracking control...It is a striking fact that the path tracking accuracy of autonomous vehicles based on active front wheel steering is poor under high-speed and large-curvature conditions.In this study,an adaptive path tracking control strategy that coordinates active front wheel steering and direct yaw moment is proposed based on model predictive control algorithm.The recursive least square method with a forgetting factor is used to identify the rear tire cornering stiffness and update the path tracking system prediction model.To adaptively adjust the priorities of path tracking accuracy and vehicle stability,an adaptive strategy based on fuzzy rules is applied to change the weight coefficients in the cost function.An adaptive control strategy for coordinating active front steering and direct yaw moment is proposed to improve the path tracking accuracy under high-speed and large-curvature conditions.To ensure vehicle stability,the sideslip angle,yaw rate and zero moment methods are used to construct optimization constraints based on the model predictive control frame.It is verified through simulation experiments that the proposed adaptive coordinated control strategy can improve the path tracking accuracy and ensure vehicle stability under high-speed and largecurvature conditions.展开更多
A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous H...A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous Hamiltonian system is multiplied by a set of multiplicative functions, then the general expression of the first integral can be obtained, An example is given to illustrate the application of the results.展开更多
Presents major achievements in researches on coordinated control with multifingered robot hands by first briefing the present status of researches on multifingered robot hands, then discussing the coordinated control ...Presents major achievements in researches on coordinated control with multifingered robot hands by first briefing the present status of researches on multifingered robot hands, then discussing the coordinated control with multifingered robot hands, and finally exploring the way of achieving autonomous grasp, and thoughts on future researches.展开更多
This paper considers the formation control problem of multi-agent systems in a distributed fashion. Two cases of the information propagating topologies among multiple agents, characterized by graphics model, are consi...This paper considers the formation control problem of multi-agent systems in a distributed fashion. Two cases of the information propagating topologies among multiple agents, characterized by graphics model, are considered. One is fixed topology. The other is switching topology which represents the limited and less reliable information exchange. The local formation control strategies established in this paper are based on a simple modification of the existing consensus control strategies. Moreover, some existing convergence conditions are shown to be a special case of our model even in the continuous-time consensus case. Therefore, the results of this paper extend the existing results about the consensus problem.展开更多
This paper elaborates upon the purpose of macro economicroponalization and inter-provincial planning and coordination under thesocialist market system. It descnbes the characteristics and orgarnzationalforms of macro ...This paper elaborates upon the purpose of macro economicroponalization and inter-provincial planning and coordination under thesocialist market system. It descnbes the characteristics and orgarnzationalforms of macro economic regions and the principle of macro economic regionalization. The six macro economic regions-Northeast China, NorthChina, Northwest China, Middle-East China, Southwest China and South China-are divided in the paper. At the end, the paper describes somemajor programs, which requires cooperation among various involvedprovinces.展开更多
【目的】分布式电源发电的随机性和波动性,给有源配电网(active distribution network,ADN)的电压控制带来了严峻的挑战,在此背景下,亟需一种高效的电压控制策略来保证ADN的安全运行。【方法】基于深度强化学习方法,提出了一种双层区域...【目的】分布式电源发电的随机性和波动性,给有源配电网(active distribution network,ADN)的电压控制带来了严峻的挑战,在此背景下,亟需一种高效的电压控制策略来保证ADN的安全运行。【方法】基于深度强化学习方法,提出了一种双层区域配电网电压控制策略。首先,以调压设备的调节特性和可控元素复杂化的特点为前提,针对ADN辐射网架结构,设计了区域协调控制区域和本地自治控制区域,分别构建每个区域的电压控制模型;然后,通过深度Q网络(deep Q-network,DQN)算法和深度确定性策略梯度(deep deterministic policy gradient,DDPG)算法对该模型进行求解,以实现实时跟踪电压变化的目的,有效解决了ADN运行过程中电压控制问题;最后,通过IEEE 33节点仿真算例对该方法进行了验证。【结果】利用DQN算法和DDPG算法分别求解协调控制区域和本地自治区域的控制变量,实现了ADN系统电压调节的实时决策,解决了ADN潮流双向流动、电压复杂多变的问题。【结论】所提控制策略控制电压偏差效果明显,具有很强的准效性和实用性。展开更多
文摘This paper conducts a series of case studies on a novel Simultaneous Path and Motion Planning (SiPaMoP) approach [1] to multiple autonomous or Automated Guided Vehicle (AGV) motion coordination in bidirectional networks. The SiPaMoP approach plans collision-free paths for vehicles based on the principle of shortest path by dynamically changing the vehicles’ paths,traveling speeds or waiting times,whichever gives the shortest traveling time. It integrates path planning,collision avoidance and motion planning into a comprehensive model and optimizes the vehicles’ path and motion to minimize the completion time of a set of tasks. Five case studies,i.e.,head-on collision avoidance,catching-up collision avoidance,buffer node generation and collision avoidance,prioritybased motion coordination,and safety distance based planning,are presented. The results demonstrated that the method can effectively plan the path and motion for a team of autonomous vehicles or AGVs,and solve the problems of traffic congestion and collision under various conditions.
基金Supported by the Foundation of Key Laboratory of Vehicle Advanced ManufacturingMeasuring and Control Technology(Beijing Jiaotong University)+1 种基金Ministry of Education,China(Grant No.014062522006)National Key Research Development Program of China(Grant No.2017YFB0103701)。
文摘It is a striking fact that the path tracking accuracy of autonomous vehicles based on active front wheel steering is poor under high-speed and large-curvature conditions.In this study,an adaptive path tracking control strategy that coordinates active front wheel steering and direct yaw moment is proposed based on model predictive control algorithm.The recursive least square method with a forgetting factor is used to identify the rear tire cornering stiffness and update the path tracking system prediction model.To adaptively adjust the priorities of path tracking accuracy and vehicle stability,an adaptive strategy based on fuzzy rules is applied to change the weight coefficients in the cost function.An adaptive control strategy for coordinating active front steering and direct yaw moment is proposed to improve the path tracking accuracy under high-speed and large-curvature conditions.To ensure vehicle stability,the sideslip angle,yaw rate and zero moment methods are used to construct optimization constraints based on the model predictive control frame.It is verified through simulation experiments that the proposed adaptive coordinated control strategy can improve the path tracking accuracy and ensure vehicle stability under high-speed and largecurvature conditions.
文摘A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous Hamiltonian system is multiplied by a set of multiplicative functions, then the general expression of the first integral can be obtained, An example is given to illustrate the application of the results.
文摘Presents major achievements in researches on coordinated control with multifingered robot hands by first briefing the present status of researches on multifingered robot hands, then discussing the coordinated control with multifingered robot hands, and finally exploring the way of achieving autonomous grasp, and thoughts on future researches.
基金the National Natural Science Foundation of China (No.60674071).
文摘This paper considers the formation control problem of multi-agent systems in a distributed fashion. Two cases of the information propagating topologies among multiple agents, characterized by graphics model, are considered. One is fixed topology. The other is switching topology which represents the limited and less reliable information exchange. The local formation control strategies established in this paper are based on a simple modification of the existing consensus control strategies. Moreover, some existing convergence conditions are shown to be a special case of our model even in the continuous-time consensus case. Therefore, the results of this paper extend the existing results about the consensus problem.
文摘This paper elaborates upon the purpose of macro economicroponalization and inter-provincial planning and coordination under thesocialist market system. It descnbes the characteristics and orgarnzationalforms of macro economic regions and the principle of macro economic regionalization. The six macro economic regions-Northeast China, NorthChina, Northwest China, Middle-East China, Southwest China and South China-are divided in the paper. At the end, the paper describes somemajor programs, which requires cooperation among various involvedprovinces.
