Globally finite-time stable three-dimensional trajectory-tracking control of underactuated UUVs

Output Feedback Spatial Trajectory Tracking Control of Underactuated Unmanned Undersea Vehicles

“…According to Lemma 1 in [10], the observer errorx 1 can converge to the equilibrium point in finite time, and the convergence time of the observer errorx 1i meet the following conditions respectively:…”

“…In recent years, the control problems of underactuated unmanned undersea vehicles (UUVs) have been the hot topic in the marine engineering [1]- [8]. These attentions originate from huge theoretical challenges arising from highly nonlinear, parameter perturbation, unmeasurable velocities and unknown environmental disturbances [2]- [4], [9], [10], and a wide range of the applications including exploration and exploitation of resources locating at deep oceanic environments, geological sampling, oceanographic observation, search and inspection of underwater structures, intelligence/surveillance/reconnaissance (ISR) and antisubmarine warfare (ASW) [1], [11], [12]. The motion control technique of underactuated UUVs is necessary and prerequisite for successfully and efficiently performing various complex missions.…”

“…Generally speaking, the traditional trajectory tracking control algorithms of marine vehicles (including ship, submarine, USV, UUV, ROV and so on) are developed under the condition that all the motion states are measurable. These full state feedback tracking controllers are proposed based on numerous nonlinear control methods, such as backstepping technique [3], [8], [17], [18], [24], [25], [29], Lyapunov's direct method [3], [17], [18], sliding mode control (SMC) [4], [10], [20], [23]- [26], [31], [32], adaptive control [17]- [19], [26], [27], etc. All the aforementioned control schemes require that all states of marine vehicles are measurable, including the linear and angular velocities in the body-fixed reference frame and the position and attitude in the inertial reference frame.…”

“…After more than half a century of development, the traditional SMC algorithm has evolved into a series of robust nonlinear control methods, including terminal SMC (TSMC), nonsingular terminal SMC (NTSMC), fast terminal SMC (FTSMC), proportional-integral-derivative SMC (PID-SMC) and so on [43]- [46]. In recent decades, SMC-class algorithms have been employed to solve the full-state-feedback motion control problem of underactuated marine vehicles [4], [10], [20], [23]- [26], [42], [47], [48]. For the discussed earlier, however, the full-state feedback control strategies may be inappropriate in many practical applications because not all states of the marine vehicles are measurable.…”

Robust Adaptive Finite-Time Tracking Control for Uncertain Euler-Lagrange Systems With Input Saturation

“…It is well known that Euler-Lagrange systems (ELSs) can describe the motion behaviors of a wide number of physical systems, including robotic manipulators [1]- [2], aircrafts [3], surface ships [4], underwater vehicles [5], etc. In parctice, the uncertainties are frequently encountered in the operations of ELSs due to unmodeled nonlinearities, unknown parameters and external disturbances, which make the tracking control problem challenging.…”