The formation maintenance of multiple unmanned aerial vehicles(UAVs)based on proximity behavior is explored in this study.Individual decision-making is conducted according to the expected UAV formation structure and t...The formation maintenance of multiple unmanned aerial vehicles(UAVs)based on proximity behavior is explored in this study.Individual decision-making is conducted according to the expected UAV formation structure and the position,velocity,and attitude information of other UAVs in the azimuth area.This resolves problems wherein nodes are necessarily strongly connected and communication is strictly consistent under the traditional distributed formation control method.An adaptive distributed formation flight strategy is established for multiple UAVs by exploiting proximity behavior observations,which remedies the poor flexibility in distributed formation.This technique ensures consistent position and attitude among UAVs.In the proposed method,the azimuth area relative to the UAV itself is established to capture the state information of proximal UAVs.The dependency degree factor is introduced to state update equation based on proximity behavior.Finally,the formation position,speed,and attitude errors are used to form an adaptive dynamic adjustment strategy.Simulations are conducted to demonstrate the effectiveness and robustness of the theoretical results,thus validating the effectiveness of the proposed method.展开更多
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat...In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs.展开更多
This paper investigates an analytical optimal pose tracking control problem for chaser spacecraft during the close-range proximity operations with a non-cooperative space target subject to attitude tumbling and unknow...This paper investigates an analytical optimal pose tracking control problem for chaser spacecraft during the close-range proximity operations with a non-cooperative space target subject to attitude tumbling and unknown orbital maneuvering.Firstly,the relative translational motion between the orbital target and the chaser spacecraft is described in the Line-of-Sight(LOS)coordinate frame along with attitude quaternion dynamics.Then,based on the coupled 6-Degree of Freedom(DOF)pose dynamic model,an analytical optimal control action consisting of constrained optimal control value,application time and its duration are proposed via exploring the iterative sequential action control algorithm.Meanwhile,the global closed-loop asymptotic stability of the proposed predictive control action is presented and discussed.Compared with traditional proximity control schemes,the highlighting advantages are that the application time and duration of the devised controller is applied discretely in light of the influence of the instantaneous pose configuration on the pose tracking performance with less energy consumptions rather than at each sample time.Finally,three groups of illustrative examples are organized to validate the effectiveness of the proposed analytical optimal pose tracking control scheme.展开更多
The significant characteristics of space non-cooperative targets include the uncertainties of dynamic parameters and behaviors.Herein,a hybrid proximity control strategy adapted to the behavior uncertainty of a non-co...The significant characteristics of space non-cooperative targets include the uncertainties of dynamic parameters and behaviors.Herein,a hybrid proximity control strategy adapted to the behavior uncertainty of a non-cooperative target is presented.First,the relative motion dynamics between the chaser and target is established in the geocentric inertial coordinate system and transcribed based on the chaser spacecraft body coordinate system.Subsequently,to facilitate proximity control under uncertain conditions,an extended state observer is designed to estimate and compensate for the total uncertainty in the relative motion dynamics.Finally,an event-triggered sliding mode control law is designed to track the target with behavior uncertainty and realize synchronization.Numerical simulations demonstrate the effectiveness of the proposed proximity control strategy for both tumbling and maneuvering targets.展开更多
This paper proposes a system for stable ladder climbing of the human-sized four-limbed robot“WAREC-1”,including the following 3 components:(a)Whole-body motion planning;(b)Rung recognition system and(c)Reaction forc...This paper proposes a system for stable ladder climbing of the human-sized four-limbed robot“WAREC-1”,including the following 3 components:(a)Whole-body motion planning;(b)Rung recognition system and(c)Reaction force adjustment.These 3 components guarantee appropriate ladder climbing motion,successful rung grub and proper reaction force distribution at contact points throughout the climbing motion,respectively.With this system,(1)Stable ladder climbing in 2-point contact gait by a human-sized robot and(2)Successful and stable climbing of an irregular ladder(with a higher or inclined rung)in both 3-point and 2-point contact gait with the capability of recognizing the target rung and the corresponding motion planning are realized,which have rarely been realized by former studies.Finally,experiment results and data of the robot ladder climbing are also presented to evaluate the proposed system.展开更多
文摘The formation maintenance of multiple unmanned aerial vehicles(UAVs)based on proximity behavior is explored in this study.Individual decision-making is conducted according to the expected UAV formation structure and the position,velocity,and attitude information of other UAVs in the azimuth area.This resolves problems wherein nodes are necessarily strongly connected and communication is strictly consistent under the traditional distributed formation control method.An adaptive distributed formation flight strategy is established for multiple UAVs by exploiting proximity behavior observations,which remedies the poor flexibility in distributed formation.This technique ensures consistent position and attitude among UAVs.In the proposed method,the azimuth area relative to the UAV itself is established to capture the state information of proximal UAVs.The dependency degree factor is introduced to state update equation based on proximity behavior.Finally,the formation position,speed,and attitude errors are used to form an adaptive dynamic adjustment strategy.Simulations are conducted to demonstrate the effectiveness and robustness of the theoretical results,thus validating the effectiveness of the proposed method.
文摘In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs.
基金This study was co-supported by the National Natural Science Foundation of China(Nos.62003371,62373379,62103446,61273351,62073343)the Outstanding Youth Fund of Hunan Provincial Natural Science,China(No.2022JJ20081)the Innovation Driven Project of Central South University,China(No.2023CXQD066).
文摘This paper investigates an analytical optimal pose tracking control problem for chaser spacecraft during the close-range proximity operations with a non-cooperative space target subject to attitude tumbling and unknown orbital maneuvering.Firstly,the relative translational motion between the orbital target and the chaser spacecraft is described in the Line-of-Sight(LOS)coordinate frame along with attitude quaternion dynamics.Then,based on the coupled 6-Degree of Freedom(DOF)pose dynamic model,an analytical optimal control action consisting of constrained optimal control value,application time and its duration are proposed via exploring the iterative sequential action control algorithm.Meanwhile,the global closed-loop asymptotic stability of the proposed predictive control action is presented and discussed.Compared with traditional proximity control schemes,the highlighting advantages are that the application time and duration of the devised controller is applied discretely in light of the influence of the instantaneous pose configuration on the pose tracking performance with less energy consumptions rather than at each sample time.Finally,three groups of illustrative examples are organized to validate the effectiveness of the proposed analytical optimal pose tracking control scheme.
基金This study was supported by the Qian Xuesen Laboratory of Space Technology,CAST(Grant No.GZZKFJJ2020001)the Open Funding of the National Defense Science and Technology Key Laboratory of Space Intelligent Control Technology(Grant No.6142208200304)the Postdoctoral Research Foundation of Sichuan University.
文摘The significant characteristics of space non-cooperative targets include the uncertainties of dynamic parameters and behaviors.Herein,a hybrid proximity control strategy adapted to the behavior uncertainty of a non-cooperative target is presented.First,the relative motion dynamics between the chaser and target is established in the geocentric inertial coordinate system and transcribed based on the chaser spacecraft body coordinate system.Subsequently,to facilitate proximity control under uncertain conditions,an extended state observer is designed to estimate and compensate for the total uncertainty in the relative motion dynamics.Finally,an event-triggered sliding mode control law is designed to track the target with behavior uncertainty and realize synchronization.Numerical simulations demonstrate the effectiveness of the proposed proximity control strategy for both tumbling and maneuvering targets.
基金This research was funded by ImPACT TRC Program of Council for Science,Technology and Innovation(Cabinet Office,Government of Japan)This study was conducted with the support of Research Institute for Science and Engineering,Waseda University+3 种基金Future Robotics Organization,Waseda University,and as a part of the humanoid project at the Humanoid Robotics Institute,Waseda UniversityThis research was also partially supported by SolidWorks Japan K.KDYDEN Corporationand KITO Corporation whom we thank for their financial and technical support.
文摘This paper proposes a system for stable ladder climbing of the human-sized four-limbed robot“WAREC-1”,including the following 3 components:(a)Whole-body motion planning;(b)Rung recognition system and(c)Reaction force adjustment.These 3 components guarantee appropriate ladder climbing motion,successful rung grub and proper reaction force distribution at contact points throughout the climbing motion,respectively.With this system,(1)Stable ladder climbing in 2-point contact gait by a human-sized robot and(2)Successful and stable climbing of an irregular ladder(with a higher or inclined rung)in both 3-point and 2-point contact gait with the capability of recognizing the target rung and the corresponding motion planning are realized,which have rarely been realized by former studies.Finally,experiment results and data of the robot ladder climbing are also presented to evaluate the proposed system.
