Article
Engineering, Aerospace
Xun Wang, Yanyan Li, Xueyang Zhang, Rui Zhang, Daoning Yang
Summary: This study investigates model predictive control (MPC) for spacecraft close-proximity maneuvering. It presents a method to improve the performance and computational efficiency of MPC for rendezvous and docking with both nonrotating and rotating client spacecraft. The proposed method utilizes an ellipsoid and linearization technique to handle collision avoidance constraints and derives an adaptive convex programming algorithm suitable for real-time implementation.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Automation & Control Systems
Juan Deng, Lin Wang, Zhixin Liu
Summary: This paper discusses the combination of attitude synchronization and rigid formation problem of multiple moving rigid bodies. By utilizing finite-time control and potential function techniques in the design of distributed control laws, the theoretical results on attitude synchronization, rigidity maintenance, and collision avoidance are simultaneously established. Moreover, the local asymptotic stability of rigid formations is shown to be achievable by transforming the stability of rigid formations into the stability of parameterized systems.
Article
Computer Science, Theory & Methods
LeSheng Jin
Summary: This work discusses two layers of meanings about uncertain information and introduces uncertain probability information as a generalization of other uncertain information. Two decision making models, relative opinion and selected opinions, are presented. Uncertain probability matrix, regular probability interval, and BUI of probability vector are introduced to model their high dimensional counterparts. The concept of relative proximity for probability vector is technically defined, enabling the definition of a unimodal function on the space of probability vectors. Properties of relative proximity in relation to BUI of probability vector are analyzed. This work is suitable for practitioners and theorists dedicated to uncertain models.
FUZZY SETS AND SYSTEMS
(2023)
Article
Engineering, Multidisciplinary
Imane Arrouch, Nur Syazreen Ahmad, Patrick Goh, Junita Mohamad-Saleh
Summary: The fusion of X-band Doppler radar and infrared sensors offers advantages in autonomous robot navigation for close proximity time-to-collision (TTC) prediction. The article discusses the challenges of poor ranging performance from infrared sensors and uncertainty in radar radiation pattern. To address these issues, an exponential Gaussian Process Regression (E-GPR) prediction model is proposed and validated through experiments, showing significant error reduction compared to other machine-learning models.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Engineering, Aerospace
Qingyu Qu, Kexin Liu, Wei Wang, Jinhu Lu
Summary: This article focuses on the relative position tracking problem of autonomous spacecraft rendezvous with collision avoidance requirement. It proposes an exploration-adaptive deep deterministic policy gradient (DDPG) algorithm for training a definite control strategy. By introducing adaptive noise and a metalearning-based idea, it reduces energy consumption and adapts to other similar scenarios effectively.
IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS
(2022)
Article
Automation & Control Systems
Antony Thomas, Fulvio Mastrogiovanni, Marco Baglietto
Summary: This paper presents a robot motion planning approach that considers landmark uncertainty in the environment and computes an exact expression for collision probability under Gaussian distribution assumptions, which is computable in real-time. Experimental and simulation results demonstrate that this approach is more effective compared to other methods.
ROBOTICS AND AUTONOMOUS SYSTEMS
(2022)
Article
Automation & Control Systems
Bin-Bin Hu, Hai-Tao Zhang, Jun Wang
Summary: This article proposes an equal-distance surrounding control method for second-order nonlinear multiagent systems, which uses a distributed estimator and adaptive distributed control law to achieve collaborative surrounding of multiple moving targets while meeting stability conditions. Experimental results with unmanned surface vessels confirm the effectiveness of the proposed method.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Engineering, Aerospace
Alexis Petit, Alessandro Rossi, Elisa Maria Alessi
Summary: This paper investigates the challenges brought by proposed constellations for communication purposes, analyzes the collision probability for each constellation, and finds that satellites of certain constellations are more likely to collide, with the decommissioning phase contributing significantly to the final collision probability.
ADVANCES IN SPACE RESEARCH
(2021)
Article
Remote Sensing
Yan Zhang, Bin Li, Hongkang Liu, Jizhang Sang
Summary: This study focuses on the short-term effects of LEO mega constellations on the space operation environment and finds that the deployment of constellations leads to a significant increase in close approaches and overall collision probability, requiring frequent orbital maneuvers to avoid collisions.
GEO-SPATIAL INFORMATION SCIENCE
(2022)
Article
Chemistry, Inorganic & Nuclear
Inga-Alexandra Bischoff, Bernd Morgenstern, Michael Zimmer, Aylin Koldemir, Rainer Poettgen, Andre Schafer
Summary: The synthesis and structure of two bis(germanocenes) and a bis(stannocene) are reported. DFT calculations show that the formation of these bis(tetrelocenes) is energetically favored over the formation of the corresponding [1]tetrelocenophanes. In the crystal structure, the tetrel(ii) centers are forced into close proximity, resulting in weak donor-acceptor interactions.
DALTON TRANSACTIONS
(2023)
Article
Automation & Control Systems
Zhixian Liu, Xiaofang Yuan, Zhe Li
Summary: This paper proposes a 3-D path planning system (3DPPS-CRPL) that considers the roll angle and path length, aiming to achieve safer and more efficient path planning by inhibiting the roll angle of the vehicle and optimizing the path length.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2022)
Article
Mechanics
Zhiwei Song, Lin Lu, Liang Cheng, Yong Liu, Guoqiang Tang, Xiaofan Lou
Summary: This study numerically investigates two-dimensional wave-induced fluid oscillations in two narrow gaps, focusing on the initial transient and final quasi-steady states. The amplitude and phase analyses reveal the characteristics of the transient and quasi-steady responses, and the roles of radiation damping and time-dependent period-averaged phase adjustment in establishing dynamic equilibrium. Simplified formulas are derived based on the intrinsic synchronization modes of quasi-steady oscillations to predict resonant and anti-resonant frequencies of the two-gaps system. The effects of incident wave amplitudes on the fluid responses and higher-order harmonics are highly dependent on frequency bands. Fourier transformations analysis explains the contributions of higher-order harmonics on overall responses.
Article
Engineering, Mechanical
Wenjia Wang, Chuanjiang Li, Yanning Guo
Summary: This paper focuses on the problem of relative position coordinated control for spacecraft formation flying with a leader spacecraft under obstacle environment. A Null-Space-Based behavioral control architecture is built to avoid obstacle/collision and maintain formation configuration, and distributed estimators are presented for each follower spacecraft. An adaptive coordinated tracking control algorithm is designed based on desired velocity and barrier Lyapunov function to ensure states satisfy time-varying constraints despite uncertainties and unknown disturbances.
NONLINEAR DYNAMICS
(2021)
Article
Engineering, Marine
Evelin Engler, Pawel Banys, Hans-Georg Engler, Michael Baldauf, Frank Sill Torres
Summary: This study focuses on the impact of inaccuracies in position, navigation, and timing data on collision avoidance reliability. The analysis of vessel traffic data from the western Baltic Sea reveals that there is a non-negligible probability of collision risks not being recognized even with position accuracies better than 10 meters.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Electrical & Electronic
Yang Yang, Qidong Liu, Haoran Tan, Zhipeng Shen, Defeng Wu
Summary: This paper addresses the issue of collision-free and connectivity-preserving formation control in a class of nonlinear multi-agent systems with external disturbances. The control objective is divided into two aspects: formation control for collision avoidance and connectivity preservation among a leader and communication-connected followers, and obstacle avoidance between followers and potential obstacles including environmental obstacles and communication-connectionless followers. A tangent-type formation error transformation function is introduced for the first aspect, while an improved continuous differentiable potential function is constructed for the second aspect. A predictor-based neural network disturbance observer (PNNDO) is developed to handle generalized disturbances. The effectiveness of the control strategy is verified through experiments with a group of quadrotors.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
