Second-Order Sliding Mode Control of a Perturbed-Crane

2015 ◽  
Vol 137 (8) ◽  
Author(s):  
Carlos Vázquez ◽  
Leonid Fridman ◽  
Joaquin Collado ◽  
Ismael Castillo
Keyword(s):  
Lyapunov Functions ◽  
Pid Controller ◽  
Degrees Of Freedom ◽  
Sliding Mode ◽  
Second Order ◽  
Convergence Time ◽  
Model Description ◽  
External Perturbations ◽  
Wide Range ◽  
Second Order Sliding Mode

A five degrees-of-freedom overhead crane system affected by external perturbations is the topic of study. Existing methods just handle the unperturbed case or, in addition, the analysis is limited to three or two degrees-of-freedom. A wide range of processes cannot be restricted to these scenarios and this paper goes a step forward proposing a control solution for a five degrees-of-freedom system under the presence of matched and unmatched disturbances. The contribution includes a model description and a second-order sliding mode (SOSM) control design ensuring the precise trajectory tracking for the actuated variables and at the same time the regulation of the unactuated variables. Furthermore, the proposed approach is supported by the design of strong Lyapunov functions providing an estimation of the convergence time. Simulations and experiments, including a comparison with a proportional-integral-derivative (PID) controller, verified the advantages of the methodology.

Novel second-order sliding mode guidance law with an impact angle constraint that considers autopilot lag for intercepting manoeuvering targets

2020 ◽  
Vol 124 (1279) ◽  
pp. 1350-1370 ◽  
Author(s):  
W.J. Zhang ◽  
Q.L. Xia ◽  
W. Li
Keyword(s):  
Finite Time ◽  
Sliding Mode ◽  
Impact Angle ◽  
Second Order ◽  
Convergence Theory ◽  
Sliding Surface ◽  
Guidance Law ◽  
Wide Range ◽  
Impact Angles ◽  
Second Order Sliding Mode

ABSTRACTA novel second-order sliding-mode-based impact angle and autopilot lag guidance law for engaging manoeuvering targets with unknown acceleration is presented in this study. A backstepping technique is applied to the design of the sliding surface. The proposed guidance law is based on a new sliding surface. It exhibits the advantage of ensuring that the sliding surface and its derivative will converge to zero in finite time while guaranteeing that the sliding surface will not cross zero until the ultimate time. The method effectively eliminates the undesired chattering of the sliding surface. To compensate for the uncertainty caused by target manoeuvering, a new observer is developed to estimate target manoeuvering. The convergence of the system is proven through a Lyapunov function and finite time convergence theory. Lastly, mathematical simulations results show that the proposed guidance law can achieve precise interception with a wide range of impact angles, thereby verifying the effectiveness of the guidance law.

Sign in / Sign up

Export Citation Format

Share Document