Multi-focus Image Fusion Based on Random Walk

Wang Zhaobin,Wang Ziye,Cui Zijing,Chen Lina,Zhang Yaonan 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.6

An effective multi-focus image fusion algorithm based on random walk is proposed in this paper. Random walk and guided filter have attracted extensive attention in image fusion. Random walk is usually used to solve probability problems and it has a good smoothing effect, and guided filter can preserve the gradient information of the image well. The combination of two algorithms can better retain the edge information of the input image. Six sets of source images and five existing methods are used in the experiment and the experimental results show that the proposed algorithm outperforms the existing methods in both subjective and objective evaluation.

EXISTENCE AND EXPONENTIAL STABILITY OF ALMOST PERIODIC SOLUTION FOR SHUNTING INHIBITORY CELLULAR NEURAL NETWORKS WITH DISTRIBUTED DELAYS AND LARGE IMPULSES

Zuo, Yi,Wang, Yaonan,Huang, Lihong,Li, Chunsheng Korean Mathematical Society 2009 대한수학회지 Vol.46 No.5

This paper considers the problem of existence and exponential stability of almost periodic solution for shunting inhibitory cellular neural networks with distributed delays and large impulses. Based on the contraction principle and Gronwall-Bellman's inequality, some sufficient conditions are obtained. The results of this paper are new and they complement previously known results.

Review of Research Advances in Fruit and Vegetable Harvesting Robots

Xiao Xu,Wang Yaonan,Jiang Yiming 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.1

The idea of applying machine technology for fruit and vegetable harvesting has been around for 50 years. Various prototypes have been developed through the joint eforts of scholars worldwide. However, the existing prototypes of harvesting robots are still in the experimental research stage due to their low harvesting efciency. With the help of information technology, related research has reached a milestone, which is full of opportunities and challenges for harvesting robot researchers. This paper briefy introduces the composition and operation process of harvesting robots, so that readers have a clear understanding of harvesting robots and their harvesting principles. Then the research results of harvesting robots at home and abroad are systematically summarized, and the research progress of harvesting robots is analyzed in detail from three aspects: rapid and accurate identifcation and positioning of target fruits, end-efector of harvesting robots, and application of harvesting path planning in harvesting robots. The results show that improving harvesting efciency is the focus and hot spot of harvesting robot research. With the impetus of information technology, how to achieve fast and accurate recognition of multiple environments and multi-information outcomes, obtain reasonable path planning, and further optimize control strategies are all important research directions.

Circumnavigation of a Moving Target in 3D by Multi-agent Systems with Collision Avoidance: An Orthogonal Vector Fields-based Approach

Hang Zhong,Yaonan Wang,Zhiqiang Miao,Jianhao Tan,Ling Li,Hui Zhang,Rafael Fierro 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.1

The problem of circumnavigating a moving target in a three dimensional setting by a network of agentswhile avoiding inter-agent collisions is addressed in this paper. A distributed control strategy is proposed for themulti-agent system to achieve three objectives: reaching the target plane with predesigned orientation, circulatingaround the target with prescribed radius, and avoiding collisions among agents. After representing the controlobjectives by three potential functions, the gradient fields of which are orthogonal to each other, the control lawthen is developed using the gradient vector field-based approach. The novelty of the proposed controller lies in theorthogonality of the vector fields, which decouples the control objectives and ensures global asymptotic convergenceto the desired motion, subject to some mild initial condition constraints. The stability and convergence analysis arepresented using Lyapunov tools, and the effectiveness of the proposed control strategy is demonstrated throughnumerical simulations.

Existence and exponential stability of almost periodic solution for shunting inhibitory cellular neural networks with distributed delays and large impulses

Yi Zuo,Yaonan Wang,Lihong Huang,Chunsheng Li 대한수학회 2009 대한수학회지 Vol.46 No.5

This paper considers the problem of existence and exponential stability of almost periodic solution for shunting inhibitory cellular neural networks with distributed delays and large impulses. Based on the contraction principle and Gronwall-Bellman's inequality, some sufficient conditions are obtained. The results of this paper are new and they complement previously known results. This paper considers the problem of existence and exponential stability of almost periodic solution for shunting inhibitory cellular neural networks with distributed delays and large impulses. Based on the contraction principle and Gronwall-Bellman's inequality, some sufficient conditions are obtained. The results of this paper are new and they complement previously known results.

Adaptive Tracking Control of Nonholonomic Mobile Manipulators Using Recurrent Neural Networks

Guo Yi,Jianxu Mao,Yaonan Wang,Siyu Guo,Zhiqiang Miao 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.3

The trajectory tracking problem is considered for a class of nonholonomic mobile manipulators in the presence of uncertainties and disturbances. First, under the assumption that the kinematic subsystem of mobile manipulator is capable of being transformed into the chained form and the dynamic subsystem of mobile manipulator is exactly known without considering external disturbances, a model-based controller is designed at the torque level using backstepping design technology. However, the model-based control may be inapplicable for practical applications, as the uncertainties and disturbances do exist in the dynamics of mobile manipulators inevitably. Thus, a Recurrent Neural Network (RNN) based control system is developed without requiring explicit knowledge of the system dynamics. The control system comprises a RNN identifier and a compensation controller, in which the RNN is utilized to identify the unknown dynamics on-line, and the compensation controller is presented to compensate the approximation error and external disturbances. The online adaptive laws of the control system are derived in the Lyapunov sense so that the stability of the system can be guaranteed. Finally, simulation results for a wheeled mobile manipulator are provided to show the good tracking performance and robustness of the proposed control method.

Fully Distributed Formation Tracking for High-order Nonlinear Multi-agent Systems with Heterogeneous Uncertainties

Weilai Jiang,Tingting Xi,Yaonan Wang,Wenqiang Zhang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.12

This article investigates the fully distributed formation tracking issue for high-order nonlinear multiagent systems (MASs) with heterogeneous uncertainties and a directed interaction graph. In order to estimate the nonlinear dynamics for followers, external disturbances as well as the control input of leader, which are all not known, a distributed extended state observer (ESO) is constructed. Depending on ESOs’ estimations, a new fully distributed formation protocol is proposed to achieve the anti-disturbance formation tracking of an unknown input leader. A specified algorithm of the protocol is given and the feasibility condition for realizing the desired formation tracking is derived. It is theoretically demonstrated that the high-order uncertain nonlinear MASs can realize the formation tracking within the proposed protocol provided the feasibility condition is satisfied. The simulations are performed for proving the validity and improvements of theoretical analysis.

An Interval-based Congestion Control Algorithm under Varying Network Conditions

Zhi Liu,Yun Zhang,Yaonan Wang 제어·로봇·시스템학회 2011 International Journal of Control, Automation, and Vol.9 No.1

A new IRED (interval random early detection) congestion control algorithm is proposed for network congestion avoidance and resource management. Different to the traditional AQM (active queue management) algorithms, the control parameters of IRED are not configured statically, and is setting as a parameter interval according to the changes of network environment. By the interval parameter design, the IRED alleviates the tuning difficulty of RED (random early detection) and shows a robust performance than RED under varying network conditions. It is proved that the stability and stability margin of the IRED control system can be guaranteed. A systematic design method for the con-figuration of parameter interval is proposed. Simulation studies show the proposed IRED algorithm achieves a robust control performance in varying network environment, which is superior to the RED and Gentle-RED algorithm.

Switching Polytopic Linear Parameter-varying Control for Hypersonic Vehicles in Full Envelope

Weilai Jiang,Chenghong Zheng,Yaonan Wang,XueJiao Sun 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.3

Gain scheduling control of hypersonic vehicles (HVs) in full envelope is studied utilizing switchingpolytopic linear parameter-varying (LPV) method. Envelope division and a new convex decomposition strategywith optimal gap metric are used to establish the switching polytopic LPV system of HVs. Sufficient conditions forstability assessment and controller synthesis for the switching polytopic LPV system are presented by average dwelltime (ADT) and multiple parameter-dependent Lyapunov functions (MPDLF). To reduce computation burden andsimplify the realization of controller, limited number of linear matrix inequalities (LMIs) are derived to dealing withswitching polytopic LPV controllers by constructing the intermediate controller variables are depend affinely on thescheduling parameter. Furthermore, to make the proposed method have better engineering value, the control matrixof LPV system studied in this paper may not have to be a constant matrix. Simulation results show the effectivenessof the switching polytopic LPV control method for HVs.

Distributed Formation Control of Quadrotor UAVs Based on Rotation Matrices without Linear Velocity Feedback

Yanjie Chen,Jiacheng Liang,Zhiqiang Miao,Yaonan Wang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.10

This paper considers the problem of the formation control for multiple underactuated quadrotor UAVs without linear velocity measurements. The objective of this paper is expected to realize smooth formation performances for a quadrotor group. A distributed formation controller is designed directly using rotation matrices to obviate the singularities associated with the Euler-angles or the ambiguity of quaternions. A two-step procedure isadopted for the control development after transforming the dynamics of each quadrotor into a new form. At first, an intermediary control variable is introduced to achieve the formation control, where some auxiliary systems are designed in the presence of lacking linear velocity measurements. Then, based on the thrust force and reference angular velocity decoded from the intermediary control variable, the torque input of each quadrotor is proposed for angular velocity tracking. The case of formation control with a virtual leader is also investigated, where at least one quadrotor has the information of the leader. The asymptotic stability of the proposed control system is analyzed by Lyapunov-like tools, and the effectiveness of the proposed control method is verified by simulation studies. Thesimulation results show that the proposed method can guide the quadrotor group to form the desired formation smoothly without linear velocity feedback, which has great potentials for the UAV group to execute the challenging mission in hostile environments.