Observer-based robust H∞ control for uncertain Markovian jump systems via fuzzy Lyapunov function

This paper investigates the problem of observer-based robust [Formula: see text] control for a class of continuous-time nonlinear Markovian jump systems (MJSs) with uncertainties, external disturbance and unavailable states that can be represented by Takagi-Sugeno (T-S) fuzzy models. Based on a mode-dependent fuzzy Lyapunov function and by introducing slack matrix variables, a sufficient condition for the existence of the state observer and observer-based robust [Formula: see text] controller for such MJSs are derived by constructing an augmented fuzzy system. Further, by means of congruent transformation in matrix and linear matrix inequality (LMI) method, the results are given in the form of LMIs that can be easily solved by using the convex optimization techniques. Moreover, we also give the result obtained via common stochastic Lyapunov function to compare with the proposed approach. Finally, a numerical example is provided to illustrate the effectiveness of the proposed approach.

Compliant behaviour of redundant robot arm - experiments with null-space

This paper presents theoretical and experimental aspects of Jacobian nullspace use in kinematically redundant robots for achieving kinetostatically consistent control of their compliant behavior. When the stiffness of the robot endpoint is dominantly influenced by the compliance of the robot joints, generalized stiffness matrix can be mapped into joint space using appropriate congruent transformation. Actuation stiffness matrix achieved by this transformation is generally nondiagonal. Off-diagonal elements of the actuation matrix can be generated by redundant actuation only (polyarticular actuators), but such kind of actuation is very difficult to realize practically in technical systems. The approach of solving this problem which is proposed in this paper is based on the use of kinematic redundancy and nullspace of the Jacobian matrix. Evaluation of the developed analytical model was done numerically by a minimal redundant robot with one redundant d.o.f. and experimentally by a 7 d.o.f. Yaskawa SIA 10F robot arm.

Testing of the Relative Precision in Local Network with Use of the Trimble Geo XR GNSS Receivers

The paper deal with testing of different GNSS measurement methods in highly accurate network for the objectives of engineering surveying. The test is comprised of a set of measurement acquired by particular GNSS methods with different observation length. For purposes of the test, an appropriate network of five points in local system was created and accurately trigonometrically measured. The result of testing is a comparison of individual methods in position using two dimensional congruent transformation and in height using one dimensional congruent transformation.

On a Simplified Technique for the Determination of the Dynamic Properties of a Linear System with Damping

The experimental methods in current use for the determination of the dynamic properties of an arbitrary finite-freedom system are based on restrictive assumptions which may often be of questionable validity. The most common assumption is that the damping matrix can be reduced to a diagonal form by a congruent transformation using the modal matrix of the undamped system. Further, the damping is normally assumed to be hysteretic, or light if viscous.Bishop and Gladwell give an excellent account of the theoretical background of the present experimental techniques. These can be divided into three groups: 1. The method of Kennedy and Pancu which obtains experimentally the complex receptance of the system and extracts its dynamic properties from vectorial plots.2. The method of Trail-Nash and Asher which is based on the experimental determination of the in-phase response of the system and requires computation to be incorporated with the experimental procedure.