28 research outputs found
Event-based visual servoing with features’ prediction
Event-based visual servoing is a recently presented approach that performs the positioning of a robot using visual information only when it is required. From the basis of the classical image-based visual servoing control law, the scheme proposed in this paper can reduce the processing time at each loop iteration in some specific conditions. The proposed control method enters in action when an event deactivates the classical image-based controller (i.e. when there is no image available to perform the tracking of the visual features). A virtual camera is then moved through a straight line path towards the desired position. The virtual path used to guide the robot improves the behavior of the previous event-based visual servoing proposal.The research leading to these results has received funding from the Spanish Ministry of Education and Science and European FEDER funds, the Valencia Regional Government and the Research and Innovation Vice-president Office of the University of Alicante, through the research projects DPI2012-32390, GV2012/102 and PROMETEO/2013/085, GRE12-17, respectively
On Kalman Active Observers
Abstract The paper introduces the Active Observer (AOB) algorithm in the framework of Kalman filters. The AOB reformulates the Kalman filter to accomplish model-reference adaptive control based on: (1) A desired closed loop system. (2) An extra equation to estimate an equivalent disturbance referred to the system input. An active state is introduced to compensate unmodeled terms, providing a feedforward compensation action. (3) Stochastic design of the Kalman matrices. Stability analysis with model errors is discussed. An example of robot force control with an external and unknown nonlinear disturbance is presented (SISO system). Another example of model-matching control for steer-by-wire (SBW) vehicles with underactuated structure is discussed (MIMO system)
Parametrization of linear controller for bumpless switching in multi-controller schemes
info:eu-repo/semantics/publishe