Some unknown elements always exist in the analysis process for the control systems, such as unmodeled dynamics, parametric uncertainties, change of the operating environment, model reduction and linearization approximations, etc., or external disturbance. So it is significative to study the disturbance process or the uncertain systems. The emergence and the development of the robust control the...

To improve the performance of a robust control, in presence of internal or external disturbance and uncertainties, to make a smooth tracking and elimination of high frequency disturbances especially in accurate systems with minimum power consumption an integration of robust optimal controller considered. Here, derivation and implementation of the proposed controller based on the combination of ...

A disturbance observer based tracking control algorithm is presented in this paper. The key idea of the proposed method is that the plant nonlinearities and parameter variations can be lumped into a disturbance term. The lumped disturbance signal is estimated based on a plant dynamic observer. A state observer then corrects the disturbance estimation in a two-step design. First, a Lyapunov-base...

This paper introduces a human-derived humanoid control concept that allows voluntary movements with automatic posture control. The concept consists of a modular control architecture, where each DOF is served by one control module. The control modules are based on the DEC model (DEC, Disturbance Estimation and Compensation). The DEC model combines sensory-derived disturbance estimates for re-act...

The state-dependent nonlinear external disturbance compensation problem is considered. No prior information about the disturbance is assumed except the periodicity of the disturbance with respect to a state variable, which is termed a ‘state-dependent periodic disturbance.’ The key idea of the proposed new adaptive compensation method is to make use of this known state-dependent periodicity. In...

In this study we present evidence that anthropogenic stressors can reduce the resilience of age-structured populations. Enhancement of disturbance in a model-based Daphnia population lead to a repression of chaotic population dynamics at the same time increasing the degree of synchrony between the population's age classes. Based on the theory of chaos-mediated survival an increased risk of exti...

In this paper, a nonlinear model of the underactuated six degrees of freedom (6 DOF) quadrotor helicopter was derived based on the Newton-Euler formalism. A new nonlinear robust control strategy was proposed to solve the stabilizing and path following problems in presence of external disturbances and parametric uncertainties. The proposed control structure consist of a sliding mode control base...