Search results for "Control Engineering"

An LMI approach to vibration control of base-isolated building structures with delayed measurements

2010

In this article, we address a convex optimisation approach to the problem of state-feedback H∞ control design for vibration reduction of base-isolated building structures with delayed measurements, where the delays are time-varying and bounded. An appropriate Lyapunov-Krasovskii functional and some free-weighting matrices are utilised to establish some delay-range-dependent sufficient conditions for the design of desired controllers in terms of linear matrix inequalities. The controller, which guarantees asymptotic stability and an H∞ performance, simultaneously, for the closed-loop system of the structure, is then developed. The performance of the controller is evaluated by means of simula…

daptive Backstepping Control of Nonlinear Hydraulic-Mechanical System Including Valve Dynamics

2010

Published version of an article from the journal: Modeling Identification and Control. Also available from publisher: http://dx.doi.org/10.4173/mic.2010.1.3 The main contribution of the paper is the development of an adaptive backstepping controller for a nonlinear hydraulic-mechanical system considering valve dynamics. The paper also compares the performance of two variants of an adaptive backstepping tracking controller with a simple PI controller. The results show that the backstepping controller considering valve dynamics achieves significantly better tracking performance than the PI controller, while handling uncertain parameters related to internal leakage, friction, the orifice equat…

Kinematic Solutions of a 7 DOF Robotic Arm Using Redundancy Circle and Fuzzy Models

2014

In this paper we have presented a method to solve the inverse kinematics problem of a redundant robotic arm with seven degrees of freedom and a human like workspace based on mathematical equations, Fuzzy Logic implementation and Simulink models. For better visualization of the kinematics simulation a CAD model that mimics the real robotic arm was created into SolidWorks® and then the CAD parts were converted into SimMechanics model.

Heuristic and Backstepping Control Strategies for Semiactive Suspension in Automotive Systems Equipped with MR Dampers

2010

Abstract This paper deals with the problem of semiactive vibration reduction in a class of automotive systems. Most conventional suspensions use passive devices to absorb impacts and vibrations, which is generally difficult to adapt to the uncertain circumstances. Semiactive suspension techniques promise a solution to the above problem with some comparatively better features than active and passive suspension devices. In this work, the semiactive suspension with magnetorheological (MR) dampers is applied for the vibration attenuation. Both backstepping and heuristic control strategies are proposed. In the design of backstepping controller, the Dahl model of the MR damper is used to estimate…

Vibration Control of a Base-Isolated Building using Wavelets

2011

Author's version of a chapter in the book: Proceedings of the 18th IFAC World Congress 2011. Also available from the publisher at: http://dx.doi.org/10.3182/20110828-6-IT-1002.03169

Selecting between CNC turning centers using a combined AHP and fuzzy approach

2019

Abstract CNC turning centers (CNCTC) are designed to perform simple turning operations, for parts having a symmetry axis. However, the flexibility of these machine-tools is increasing rapidly. Supplementary modules, such as Y-axis and driven tools, which allow the user to perform milling operations, are fitted on CNCTC. Selecting the proper CNCTC, out of a great number of commercially available solution has become a very difficult task. A combined approach using Analytic Hierarchy Process (AHP) and fuzzy logic is proposed, to assist the decision-making process of choosing between three variants of CNCTC.

SAVU: A Statistical Approach for Uncertain Data in Dynamics of Axially Moving Materials

2012

In physics and engineering problems, model input is never exact. The effect of small uncertainties on the solution is thus an important question. In this study, a direct statistical-visual approach to approximate the solution set is investigated in the context of axially moving materials. The multidimensional probability distribution for the input uncertainties is assumed known. It is considered as a deterministic object, which is then mapped through the model. The resulting probability density of the model output is visualized. The proposed system consists of three non-trivial parts, which are briefly discussed: a multidimensional sampler, a density estimator, and a high dynamic range (HDR…

Discrete-time static output-feedback H<inf>∞</inf> controller design for vehicle suspensions

2014

This paper provides a direct and practical presentation of a novel methodology for static output-feedback controller design. The proposed design strategy has been successfully applied in the fields of control systems for seismic protection of large buildings and multi-building structures, control of offshore wind turbines, and active control of vehicle suspensions. The positive results obtained in these initial applications clearly indicate that this approach could be an effective tool in a large variety of control problems, for which an LMI formulation of the statefeedback version of the problem is available. The main objective of the paper is to facilitate a brief and friendly presentatio…

DYNAMIC MODELING TOOLS FOR SOLAR POWERED DESALINATION PROCESSES DURING TRANSIENT OPERATIONS

2007

Prosthetic design and prototype development

2020

Abstract In recent years, there has been worldwide interest in improvement of the mobility of people with lower-limb amputations. Despite significant development of new technologies over the last decade, commercial below-knee and above-knee prostheses are still energetically passive devices. However, many locomotive functions, like walking up stairs and slopes, need significant power in the knee and ankle joints. The additional power for carrying out these previously mentioned activities needs to be achieved by means of external energy sources, which should be integral prosthetic components. This chapter presents preliminary investigations and development towards an active robotic prosthesi…