In this paper, a second-order non-singular fast terminal sliding mode controller is proposed for robotic manipulators in the presence of uncertainties and disturbances. Adaptive control is used to obtain robustness to system uncertainties and disturbances. The improved high-gain observer is designed to estimate the speed information, which makes the controller more applicable in practice. Theorem proof and simulations demonstrate the effectiveness of the proposed controller.

In this article, distributed tracking control is studied for multiple Euler-Lagrange systems in the presence of external disturbances and input saturation. Specifically, full-state constraints, input saturation, communication delays, and unmeasured velocities are all considered simultaneously. First, a novel event-triggered scheme is developed to save the communication source and reduce computational load. Second, the anti-saturation compensation algorithm is exploited to compensate for system saturation.Third, an adaptive law is designed to offset external disturbances. Moreover, a high-gain observer is employed to estimate unmeasured velocities.Theorem analysis shows the stability of the closed-loop system, and numerical simulations are provided to verify the effectiveness of the proposed control strategy.

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In this paper, the issue of distributed tracking control is studied for multiple Euler–Lagrange systems in presence of external disturbances and input saturation. Specifically, the full-state constraints, input saturation, communication delay, and unmeasured velocity are also considered simultaneously. Firstly, an adaptive distributed state observer is introduced to obtain the leader's time-varying position information, at the same time, a delay function is employed to compensate the communication delay. Moreover, the event-triggered control scheme is developed to reduce communication source and computation load, and the anti-saturation compensation algorithm is exploited to compensate for the influence of system saturation. Thirdly, an adaptive law is designed to offset external disturbances. What’s more, the high-gain observer is used to estimate the unmeasured velocities. Theorem analysis shows that the system errors can converge to zero. Finally, numerical simulations are present to verify the effectiveness of the proposed control strategy.