In this article, a finite-time control scheme is proposed for quadrotor unmanned aerial vehicle (UAV) with external disturbance. First, disturbance observer designed to cope Then, nonsingular terminal sliding-mode developed, which avoids singularity problem of conventional control. By Lyapunov stability theory, it proved that the controller guarantees tracking errors converge zero in finite time. Finally, effectiveness and superiority strategy verified by compared simulation.

Due to a lack of medical resources or oral health awareness, diseases are often left unexamined and untreated, affecting large population worldwide. With the advent low-cost, sensor-equipped smartphones, mobile apps offer promising possibility for promoting health. However, best our knowledge, no (mHealth) solutions can directly support user self-examine their condition. This paper presents OralCam, first interactive app that enables end-users' self-examination five common conditions...

This study presents a new controller that is integrating sliding mode control method, backstepping technique with disturbance observer (DO) for the flexible air‐breathing hypersonic vehicle (FAHV). A control‐oriented model (COM) firstly established based on engineering background of FAHV, and COM decomposed into velocity subsystem an altitude subsystem, then controllers DO are designed them. The developed surface exponential form can accelerate convergence speed state. Furthermore, time...

For analyzing the problem of frequent wideband oscillations in grid-connected renewable energy generation systems, an analysis method based on small-world networks and fast-slow dynamics is proposed. A direct-driven permanent magnet synchronous generator (DPMSG) was chosen as example to discuss process bursting a single system with both alternating large-amplitude micro-amplitude due multi-timescale coupling effect introduced by disturbance. Meanwhile, complex network consisting multiple...

In this paper, the finite-time control design problem for a class of nonlinear systems with matched and mismatched uncertainty is addressed. The scheme designed by integrating multi power reaching (MPR) law disturbance observer (FTDO) into integral sliding mode control, where novel surface designed, FTDO applied to estimate uncertainty. Then fixed-time reachability MPR analyzed, stability closed-loop system proven in framework Lyapunov theory. Finally, numerical simulation application flight...

AC-DC hybrid spot networks contain strong redundancy. It further enhances the power supply reliability of network systems and is helpful for integration distributed energy resources (DERs). However, there are few stability analysis studies networks. Focusing on network, which adopts a unified control strategy, its problem studied in this article. A mathematical model each unit constructed system. Via linearization spatial state equations, small-signal established under different operation...

The widespread use of electric vehicles (EVs) is becoming an imminent trend. Research has been done on the scheduling EVs from perspective charging characteristic. There a lack systematic studies considering EVs, power grid, utilization large scale wind energy, improvement in safety and economy or traffic jams transport system caused by number driven to stations all together. In this paper, mathematical models are built for both smart Vehicle-to-Grid operation with distribution grid...

Based on screw theory and the principle of one- leg driving by an independent motor, a methodology for structural synthesis fully-decoupled three-rotational one-translational (3R1T) parallel mechanisms is proposed analysing characteristics input-output relationships mechanisms. Firstly, desired forms both direct inverse Jacobian matrices are constructed virtue theory; this in order to satisfy demand that these two should be non-zero diagonal matrices. Secondly, effective screw, actuated...

With the prevalence of renewable energy source in power system, it is necessary to appraise voltage stability integration system by probabilistic methods. The traditional Markov Chain Monte Carlo (MCMC) simulation could show great calculation precision for assessment, but always involved with complicated sampling iterations because Gibbs method currently used MCMC simulation. Instead method, this paper presents application slice assessment source. Firstly, models generation are constructed....

The nonlinear finite element solution procedures for the inclined cable due to both static and timevarying support movements are formulated. results validated by exact catenary profile of cable. in-plane vibrations excited sinusoidal time-varying motions then analyzed with method. Some numerical presented discussed.

There may be complex interaction between the converter control systems of wind power and MMC-HVDC, which will lead to sub-/super-synchronous oscillation threaten safe stable operation system. The relevant events have been reported in Guangdong Nan'ao, Shanghai Nanhui Zhangbei projects. Rudong offshore project is first transmission system China, it still under construction. Therefore, great significance carry out research on risk analysis suppression measures sub-synchronous MMC-HVDC First,...

Bifurcation and chaos for electromechanical coupling torsional vibration in rolling mill system driven by DC motor is studied this paper. Considering the devices under unsaturated magnetic circuit, dynamical equation of drive deduced using dissipation Lagrange equation. The equivalent low-dimensional bifurcation equation, which can reveal influence parameters on nonlinear dynamic characteristics, obtained reducing dimensionality method Lyapunov-Schmidt reduction, static characteristic...

Inspired by dual-arm-like manipulation, a novel 6-DOF parallel manipulator with two spherical-universal-revolute limbs is proposed. Compared general manipulators six limbs, this new actuated spherical motion generators has only which brings advantages such as fewer active for avoiding interference, larger reachable and orientational workspace complex operating, more actuators integrated in modules decreasing installation errors increasing compactness. In paper, the kinematics of solved...

Abstract Considering the dynamic behavior of doubly‐fed induction generators (DFIGs) under influence random factors, this paper not only analyzes phenomenon stochastic instability and bifurcation a DFIG variable in its space when they are affected by environmental noise, but also proposes method based on Tkagi–Sugneo (T–S) fuzzy control strategy to bifurcation. First, four‐dimensional model is established using multiplicative white noise simulate electrical variables, central manifold theory...

Summary The unstable operation of a direct‐drive permanent magnet synchronous generator (DPMSG) is exacerbated by periodic oscillation, having significant impact on the safe and stable functioning wind energy generation systems. This paper proposes an approximate solution method for analyzing oscillation Hopf bifurcation suppressing its through H ∞ robust control. Firstly, three‐dimensional nonlinear dynamic model DPMSG constructed. Secondly, system with changes in internal parameters solved...

Summary To address the problem of bursting oscillations in doubly fed induction generator (DFIG) systems under external disturbances, an analysis method based on fast‐slow dynamics and a control strategy adaptive high‐order differential feedback controller (AHODFC) is proposed. The was adopted to reveal formation mechanism from DFIG system owing multi‐timescale coupling effect perturbation, that is, oscillation form with alternating large‐amplitude micro‐amplitude oscillation. A AHODFC...

Summary To address the grid stability problem caused by random changes in cable impedance when an offshore wind power generation system is sent out via a cable, this study proposes stochastic analysis method for doubly‐fed considering frequency variation of parameters based on polynomial approximation theory, which can be analyzed equating change public coupling point as deterministic problem. First, dynamics model farm established variation. Second, using containing approximated equivalent...

Abstract Wind power has become the focus of new energy generation by its abundant resources and clean environmentally friendly features. However, as proportion wind connected to grid rises, there is a risk causing sub-synchronous oscillation. For problem oscillation, an additional damping control strategy taking into account rotor side converter turbine was proposed. This paper establishes connection model, including turbine, MMC, transmission line, analyzes mechanism oscillation using...

The WTO system has largely achieved procedural fairness, yet substantial challenges persist in addressing the equity of legal remedies and enforcement, particularly amid significant disparities economic power among member states. Such imbalances necessitate a nuanced consideration design to ensure that fairness transcends aspects reflects substantive outcomes. In context, Intellectual Property (IP) retaliation emerges as an innovative temporary method address these imbalances, offering...