7 research outputs found
A sampled-data formulation for boundary control of a longitudinal elastic bar
The sampled-data boundary control problem for a longitudinal flexible bat is formulated as a linens discrete-time control problem in an infinite-dimensional state space. With zero-order-hold applied to the control channel, the system is lifted into an infinite sequence of constant control problems, The finite-dimensional approximation of the discrete-time system is controllable-observable if the sampling period satisfies some in-equality constraints, which are related to the associated eigenvalues
An O(T-2) boundary layer in sliding mode for sampled-data systems
The use of a discontinuous control law (typically, sign functions) in a sampled-data system will bring about chattering phenomenon in the vicinity of the;sliding manifold, leading to a boundary layer with thickness O(T), where T is the sampling period. However, by proper consideration of the sampling phenomenon in the discrete-time sliding mode control design, the thickness of the boundary layer can be reduced to O(T-2). In contrast to discontinuous control for continuous-time VSS, the discrete-time sliding mode control need not be of switching type
Discrete-time sliding mode control on a flexible truss structure
Implementation of discrete-time sliding mode control on a sampled-data system leads to sliding motion in an O(T-2) boundary layer of the discontinuity surface, where T is the sampling period. A truss panel structure vibration control experiment is conducted to demonstrate the effectiveness of the proposed method. This paper utilizes a truncated model to characterize the models of interest and treats all the high frequency modes as disturbances. The experiment includes system identification, state observer design, and discrete-time sliding mode control