Terminal Sliding Mode-Based Consensus Tracking Control for Networked Uncertain Mechanical Systems on Digraphs

Abstract

This brief investigates the finite-time consensus tracking control problem for networked uncertain mechanical systems on digraphs. A new terminal sliding-mode-based cooperative control scheme is developed to guarantee that the tracking errors converge to an arbitrarily small bound around zero in finite time. All the networked systems can have different dynamics and all the dynamics are unknown. A neural network is used at each node to approximate the local unknown dynamics. The control schemes are implemented in a fully distributed manner. The proposed control method eliminates some limitations in the existing terminal sliding-mode-based consensus control methods and extends the existing analysis methods to the case of directed graphs. Simulation results on networked robot manipulators are provided to show the effectiveness of the proposed control algorithms.

Robust Continuous Control for a Class of Mechanical Systems Based on Nonsingular Terminal Sliding Mode

“…The proposed controller (2), (5), (7), (13), and filter (24) is implemented in a real-time data acquisition board dSPACE using a sample time of T s = 0.0001 seconds and the Euler fixed-step solver. The only output of the system is given by the cylinder's position, in order to have access to velocity is used a differentiator based on the model proposed in [25], [50].…”

“…The design of trajectory tracking controllers has important usages in mechanical systems with electrical, pneumatic, or hydraulic actuators [1]- [4]. In the past decades, several robust control techniques have been established for the tracking control of uncertain mechanical systems such as sliding mode control [5]- [7], fuzzy control [8]- [10], adaptive control [11], [12], PID control [13]- [16], among others. Each controller design has its advantages, and disadvantages such as discontinuous controllers under certain conditions are robust against uncertainties and perturbations.…”

Adaptive fuzzy finite‐time consensus tracking for multiple Euler‐Lagrange systems with unknown control directions

“…In practical applications, the consensus control for ELSs usually requires a finite-time convergence rate, so it is of great importance to consider the finite-time consensus for multi-agent systems (MASs), 28 especially for multiple ELSs. [29][30][31][32][33][34][35] For example, 28 studied the observer-based adaptive finite-time containment control for nonlinear MASs; 32 investigated the finite-time consensus of multiple ELSs with sensor saturations; 33 considered the containment control of multispacecraft systems under finite-time convergence; 34 investigated the terminal sliding mode consensus tracking problem of multiple ELSs. Based on traditional backstepping technique, 35 proposed the finite-time consensus tracking control of networked ELSs, but the calculation complexity problem cannot be avoided.…”

“…Compared with the traditional backstepping control and DSC for single ELS or multiple ELSs in References 14‐17,20‐24, we propose a CFBC scheme for multiple ELSs to avoid the differential of virtual signal by using FTCF and compensate the filtering error by using error compensation signals, which can further simplify the control algorithm and improve the control quality. Compared with CFBC scheme for nonlinear systems and nonlinear MASs in Reference 25‐27, the fractional power based virtual signal is designed, which can guarantee the closed‐loop system is finite‐time convergence. Moreover, the system uncertainties and external disturbances are considered simultaneously and the unknown dynamics are approximated by FLS, which can guarantee the proposed algorithm is more adopted to complex environment. Compared with the finite‐time control schemes for multiple ELSs in References 33‐36, the UCDs problem is further studied through the Nussbaum function‐based controller design. Although Reference 48 considered the finite‐time CFBC for nonlinear MASs with UCDs, but the sign function based error compensation signals are designed, which may appear the chattering problem.…”

“…Compared with the finite‐time control schemes for multiple ELSs in References 33‐36, the UCDs problem is further studied through the Nussbaum function‐based controller design. Although Reference 48 considered the finite‐time CFBC for nonlinear MASs with UCDs, but the sign function based error compensation signals are designed, which may appear the chattering problem.…”