In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are limited.Our study introduces an advanced control algorithm based on hierarchical reinforcement l...In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are limited.Our study introduces an advanced control algorithm based on hierarchical reinforcement learning to enhance these capabilities for critical missions like target search,positioning,and relay guidance.Structured on a dual-layer model,the algorithm’s lower layer manages basic aircraft maneuvers for optimal flight,while the upper layer processes battlefield dynamics,issuing precise navigational commands.This approach enables accurate navigation and effective reconnaissance for lead aircraft.Notably,our Hierarchical Prior-augmented Proximal Policy Optimization(HPE-PPO)algorithm employs a prior-based training,prior-free execution method,accelerating target positioning training and ensuring robust target reacquisition.This paper also improves missile relay guidance and promotes the effective guidance.By integrating this system with a human-piloted lead aircraft,this paper proposes a potent solution for cooperative aerial warfare.Rigorous experiments demonstrate enhanced survivability and efficiency of loyal wingmen,marking a significant contribution to Unmanned Aerial Vehicles(UAV)formation control research.This advancement is poised to drive substantial interest and progress in the related technological fields.展开更多
In electronics packaging the time-pressure dispensing system is widely usedto squeeze the adhesive fluid in a syringe onto boards or substrates with the pressurized air.However, complexity of the process, which includ...In electronics packaging the time-pressure dispensing system is widely usedto squeeze the adhesive fluid in a syringe onto boards or substrates with the pressurized air.However, complexity of the process, which includes the air-fluid coupling and the nonlinearuncertainties, makes it difficult to have a consistent process performance. An integrated dispensingprocess model is first introduced and then its input-output regression relationship is used todesign a run to run control methodology for this process. The controller takes EWMA scheme and itsstability region is given. Experimental results verify the effectiveness of the proposed run to runcontrol method for dispensing process.展开更多
Due to the paramagnetic property of liquid oxygen,the Kelvin force can be induced in liquid oxygen under non-uniform magnetic field.Based on the volume of fluid(VOF)model,the positioning effect of the force in liquid ...Due to the paramagnetic property of liquid oxygen,the Kelvin force can be induced in liquid oxygen under non-uniform magnetic field.Based on the volume of fluid(VOF)model,the positioning effect of the force in liquid oxygen tanks is analyzed under various Bond numbers(Bo)and magnetic Bond numbers(Bom).The results show that the magnetic field has the effect of repositioning the liquid oxygen in the tank when the gravity field is not enough or absent.Additionally,the gas-liquid interface has a periodic fluctuation during the process due to the inhomogeneous Kelvin force distribution,and more effective suppression of fluctuation can be achieved under the condition of a larger Bom.The new method of controlling gas-liquid interface of liquid oxygen tank under micro gravity condition is hoped to be developed in the future.展开更多
The fast and accurate collision detection and distance calculation between geometric models is fundamen-tal in robotics, manufacturing and computer-simulated en-vironments. This paper surveys the state of the art in t...The fast and accurate collision detection and distance calculation between geometric models is fundamen-tal in robotics, manufacturing and computer-simulated en-vironments. This paper surveys the state of the art in the theory and algorithms of distance and pseudo distance func-tions between convex sets. An overview on the existing results, including fast algorithms for distance calculation, definitions and properties of various pseudo distance functions (the J-function, the growth distance, and the pseudo minimum translational distance), is presented. The distance and pseudo distance functions are versatile in a wide range of areas. Their applications in robot motion planning, grasp analy-sis/synthesis, form error evaluation, and engineering optimi-zation is demonstrated.展开更多
基金This study was co-supported by the Natural Science Basic Research Program of Shaanxi,China(No.2022JQ-593)the Key R&D Program of Shaanxi Provincial Department of Science and Technology,China(No.2022GY-089)the Aeronautical Science Foundation of China(No.20220013053005).
文摘In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are limited.Our study introduces an advanced control algorithm based on hierarchical reinforcement learning to enhance these capabilities for critical missions like target search,positioning,and relay guidance.Structured on a dual-layer model,the algorithm’s lower layer manages basic aircraft maneuvers for optimal flight,while the upper layer processes battlefield dynamics,issuing precise navigational commands.This approach enables accurate navigation and effective reconnaissance for lead aircraft.Notably,our Hierarchical Prior-augmented Proximal Policy Optimization(HPE-PPO)algorithm employs a prior-based training,prior-free execution method,accelerating target positioning training and ensuring robust target reacquisition.This paper also improves missile relay guidance and promotes the effective guidance.By integrating this system with a human-piloted lead aircraft,this paper proposes a potent solution for cooperative aerial warfare.Rigorous experiments demonstrate enhanced survivability and efficiency of loyal wingmen,marking a significant contribution to Unmanned Aerial Vehicles(UAV)formation control research.This advancement is poised to drive substantial interest and progress in the related technological fields.
基金This project is supported by National Natural Science Foundation of China (No.50390063, 50390064), Research Grant Council of HK SAR (CityU1086/01E)and City University of HK Applied R&D Project(No.9620002).
文摘In electronics packaging the time-pressure dispensing system is widely usedto squeeze the adhesive fluid in a syringe onto boards or substrates with the pressurized air.However, complexity of the process, which includes the air-fluid coupling and the nonlinearuncertainties, makes it difficult to have a consistent process performance. An integrated dispensingprocess model is first introduced and then its input-output regression relationship is used todesign a run to run control methodology for this process. The controller takes EWMA scheme and itsstability region is given. Experimental results verify the effectiveness of the proposed run to runcontrol method for dispensing process.
基金supported by the Natural Science Foundation of China(No.51706190)the State Scholarship Fund of China Scholarship Council。
文摘Due to the paramagnetic property of liquid oxygen,the Kelvin force can be induced in liquid oxygen under non-uniform magnetic field.Based on the volume of fluid(VOF)model,the positioning effect of the force in liquid oxygen tanks is analyzed under various Bond numbers(Bo)and magnetic Bond numbers(Bom).The results show that the magnetic field has the effect of repositioning the liquid oxygen in the tank when the gravity field is not enough or absent.Additionally,the gas-liquid interface has a periodic fluctuation during the process due to the inhomogeneous Kelvin force distribution,and more effective suppression of fluctuation can be achieved under the condition of a larger Bom.The new method of controlling gas-liquid interface of liquid oxygen tank under micro gravity condition is hoped to be developed in the future.
基金supported by the National Natural Science Foundation of China(Grant Nos.50175014,50390063 and 59990470).
文摘The fast and accurate collision detection and distance calculation between geometric models is fundamen-tal in robotics, manufacturing and computer-simulated en-vironments. This paper surveys the state of the art in the theory and algorithms of distance and pseudo distance func-tions between convex sets. An overview on the existing results, including fast algorithms for distance calculation, definitions and properties of various pseudo distance functions (the J-function, the growth distance, and the pseudo minimum translational distance), is presented. The distance and pseudo distance functions are versatile in a wide range of areas. Their applications in robot motion planning, grasp analy-sis/synthesis, form error evaluation, and engineering optimi-zation is demonstrated.
