This paper investigates the prescribed performance attitude tracking control problem of a rigid spacecraft with uncertain dynamics and bounded disturbances. By suitable selection configuration error function, trajectory on SO(3) is transformed into point stabilisation an dynamic system in associated Lie algebra. The predefined transient indexes, which include maximum steady-state overshoot, minimum convergence rate vector, are characterised as inequality constraints. For controller design,...

This paper investigates the prescribed performance fixed-time tracking control problem for a class of second-order nonlinear systems with bounded disturbance and actuator saturation limit. In order to facilitate controller development, we introduce function output error transformation technique transform dynamics inequality constraints an equivalent unconstrained one. Different from existing work on guaranteeing control, incorporate sliding mode surface into design procedure cope...

This paper investigates the optimal spacecraft reorientation issue while adhering to attitude pointing and actuator constraints. To handle second-order nature of constraint in dynamics, a high-order control barrier function (HOCBF) is developed, ensuring forward invariance set via Lyapunov-like conditions. A fixed-time stability (FxTS) Lyapunov introduced achieve using sliding mode techniques. The problem formulated as quadratic programming (QP) optimisation with limits, leveraging slack...

In this paper, we investigate the finite-time attitude tracking control problem for a rigid spacecraft on special orthogonal group ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$SO(3)$</tex-math></inline-formula> ). The exponential coordinates, derived from and logarithmic maps of Lie group, are utilized to describe error almost globally unique except zero measure set which map is double valued. To avoid...

This brief investigates the fixed-time tracking problem for uncertain nonlinear systems with input saturation constraint under event-triggered scheme. An adaptive controller is proposed to drive error a residual set in fixed time, which can eliminate of "explosion complexity". Furthermore, order decrease communication burden between and actuator while maintaining system control performance, we co-design strategy, guarantees that injected into only when predefined event occurs. In addition,...

Abstract This paper investigates the fixed‐time attitude tracking problem for rigid spacecraft in presence of inertial uncertainties, external disturbances, actuator faults, and input saturation constraints. The logarithm map is first utilized to transform on S O (3) into stabilization one its associated Lie algebra ( ). A novel nonsingular fixed‐time‐based sliding mode designed, which not only avoids singularity but also guarantees that convergence time errors along surface independent...

This paper investigates the continuous composite control scheme for tracking of nonlinear system with mismatched disturbances, input saturation and full-state constraints. Based on fixed-time stability theory, a novel disturbance observer is proposed, which switches from uniform second-order sliding mode high-degree term to classical super-twisting observer. Then, command filtered backstepping designed enforce error into small neighbourhood origin in fixed time while constraint are...

&lt;abstract&gt;&lt;p&gt;Global exponential periodicity of nonlinear neural networks with multiple time-varying delays is investigated. Such cannot be written in the vector-matrix form because existence delays. It noted that although network has been investigated by Lyapunov-Krasovskii functional method literature, sufficient conditions linear matrix inequality have not obtained. Two sets are established and to ensure two arbitrary solutions attract each other exponentially. This a key...

This paper addresses the global finite-time attitude stabilisation problem on special orthogonal group (SO(3)) for a rigid spacecraft via homogeneous feedback approach. Considering topological and geometric properties of SO(3), logarithm map is utilised to transform SO(3) into one its associated Lie algebra (so(3)). A model-independent discontinuous state plus dynamics compensation scheme constructed achieve in coordinate-invariant way. In addition, address absence angular velocity...

This paper studies the prescribed performance tracking control problem for a pure-feedback nonlinear system with full-state constraints. By incorporating asymmetric barrier Lyapunov functions into dynamic surface control, we develop an adaptive scheme, which can ensure that all closed-loop signals remain bounded and constraints are not violated. Furthermore, explore event-triggered systems constraints, save limited computing communication resources. The numerical simulations provided to...

This paper investigates the attitude trajectory tracking problem of a rigid spacecraft subject to external disturbances and full-state constraint under event-triggered scheme. By incorporating barrier Lyapunov function (BLF) into dynamic surface technique, we develop coordinate-free integral sliding mode controller which cannot only deal with state but also enforce error converge vicinity origin. To save computation communication resources, modified mode-based robust is proposed, in control...

Abstract This paper addresses appointed‐time attitude coordinated control problem of multiple spacecraft under the directed communication topology in presence input saturation. With only a subset spacecrafts being able to access information reference trajectory, distributed observer is developed for each estimate virtual leader's state fixed time. Subsequently, ensure tracking error can achieve preassigned transient and steady performance, an adaptive backstepping controller synthesized by...

In this paper, the attitude tracking problem for rigid body with model uncertainties and external disturbances is investigated in a coordinate-free way. A continuous adaptive-gain second-order sliding mode controller designed to ensure establishment of real finite time, then predefined nonsingular fast surface further implies finite-time stability error vector angular velocity vector. The key feature proposed that it does not require knowledge boundary disturbance gradient. rigorous...

This paper investigates dynamical behaviors of the stochastic Hopfield neural networks with mixed time delays. The delays under consideration comprise both discrete time-varying and distributed time-delays. By employing theory functional differential equations linear matrix inequality (LMI) approach, some novel criteria on asymptotic stability, ultimate boundedness, weak attractor are derived. Finally, a numerical example is given to illustrate correctness effectiveness our theoretical results.

A new prediction model was presented to predict the drag torque of a disengaged wet clutch in order analyze formation mechanism multi-disk shifting clutch.A radial velocity oil film deduced according Navier-Stokes equation based on laminar flow viscosity hydrodynamics and considering centrifugal effect cooling lubricating clearance.Then analyzed.Results showed that force caused shrinking film.The equivalent outer radius introduced describe phenomenon,and resolved by utilizing surface tension...

This paper proposes a geometric control scheme to stabilize the full-actuated mobile manipulating unmanned aerial system (MM-UAV) desired configuration. For this purpose, we firstly describe kinematics and dynamics of by incorporating standard concepts from Lie group algebra. Then, controller with proportional derivative (PD) linear action nonlinear gravity compensating is designed introducing Morse function. Finally, number example presented demonstrate effectiveness controller.

&lt;abstract&gt;&lt;p&gt;This paper discusses the exponential stability of periodic solutions for stochastic neural networks with multiple time-varying delays. For these networks, sufficient conditions in linear matrix inequality forms are rare literature. We constructed an appropriate Lyapunov-Krasovskii functional to eliminate items delays and establish some forms, ensure solutions. Several examples provided demonstrate that our results effective less conservative than previous...

In this paper, we investigated the formation isolation regulation issue regarding multiple autonomous underwater vehicles (AUVs) characterized by a "leader-follower" framework. Considering cooperative-competitive relationship among follower AUVs and impact of unknown external disturbances, an extended state observer was designed based on backstepping to mitigate these event-triggered control scheme realize two-part consensus within multi-AUV system. Through rigorous theoretical analysis, it...

In this paper, we investigate the formation isolation regulation issue regarding multiple Autonomous Underwater Vehicles (AUVs) characterized by a “leader–follower” framework. Considering cooperative–competitive relationship among follower AUVs and impact of unknown external disturbances, an extended state observer is designed based on backstepping to mitigate these event-triggered control scheme realize two-part consensus within multi-AUV system. Through rigorous theoretical analysis, it...