Figure - available from: IET Control Theory & Applications
This content is subject to copyright. Terms and conditions apply.
Source publication
This paper proposed an adaptive super-twisting (AST)-based fractional-order sliding mode control algorithm under disturbances for redundantly actuated cable driving parallel robots. A novel fractional-order non-singular fast terminal sliding mode surface is constructed, and the fast response convergence and accuracy tracking performance can be obta...
Similar publications
![Fig. 1: Schematic diagram of a Stewart platform [2].](profile/Johann-Reger/publication/359184566/figure/fig1/AS:1132754469167105@1647081119889/Schematic-diagram-of-a-Stewart-platform-2_Q320.jpg)
In this paper, a third-order sliding mode control (SMC) with a super-twisting finite time observer is proposed for the position control of a Stewart platform. The Stewart platform is a parallel robotic manipulator with a fixed base platform connected to a movable top platform with the help of six actuator legs. The proposed control makes the movabl...
Citations
... Simulink environment of MATLAB software with sampling time equal to 0.01 s is utilized for simulation. In this robot, a mass is suspended from two variablelength cables while its end-effector fluctuates out of a vertical plane [27]. By this means, q = [x, y, z] T is the vector of configuration variables. ...
Point‐to‐point control of underactuated mechanical systems is a challenging problem, especially if some of the system's parameters are uncertain. A popular method to stabilize underactuated manipulators is total energy shaping, in which a new Hamiltonian function is assigned to the closed‐loop system while a set of partial differential equations (PDEs) should be solved. In this study, an adaptive total energy shaping controller based on the approach called interconnection and damping assignment passivity‐based control (IDA‐PBC) for some underactuated robots is designed. The proposed method can overcome uncertainties in the dynamical parameters and also the parameters of the input mapping matrix under the satisfaction of the PDEs. The stability of the desired pose is ensured by the Lyapunov approach via suitable design of adaptation laws without the requirement for the persistence of excitation condition or other similar conditions. The results are applied to a 3‐DOF underactuated manipulator and verified by simulations.
... Hence, it is pivotal to analyze and design a noise compensator to make the controller more stable and robust. Regarding CDS, the noise components frequently occur in many ways Hao et al. (2016), Ramírez-Neria et al. (2015), and Zhengsheng et al. (2021) such as unknown variable forces acting on its actuator's vertical system because of the sudden change of body weight, or the dry and viscous friction force, or the parametric uncertainties of the mathematical model, etc. In Hao et al. (2016), a fast friction approximator derived from the Lyapunov design process is proposed to estimate unknown frictions of each electrical cylinder of a 6-DOF parallel manipulator. ...
The paper proposes an adaptive Lyapunov-based nonlinear model predictive control to cope with the problems in nonlinear systems subjecting to system constraints and unknown disturbances of the parallel car driving simulator. Commonly, standard nonlinear controllers could guarantee the overall system stability for the parallel structure. However, the constraints tend to impact the control performance and stability adversely. Therefore, model predictive control (MPC) plays a vital role in the proposed technique to explicitly consider all the practical constraints and simultaneously enhance the system's robustness. Nevertheless, the accuracy of the modeling process has a significant effect on the MPC performance, and thus, the convergence cannot be guaranteed in the presence of the model uncertainties. To overcome this problem, by the merit of the fuzzy adaptive law, the control system takes the disturbances and unmodelled parameters into account. Moreover, the feasibility and stability of the approach, which is the fundamental problem of MPC, are ensured according to the Lyapunov-based nonlinear controller, Backstepping aggregated with Sliding Mode Control (SMC), and hence inherit advantages of these controls. Simulation results show the efficiency and superior constituted controllers of the proposed method.
