Linear Control of a Nonlinear Equipment Mounting Link

QFT Control of a Two-Link Rigid-Flexible Manipulator

This paper evaluates a new and simple controller design method based on QFT (quantitative feedback theory) for a two-link manipulator whose first link is rigid and the second is flexible. A piezoelectric patch is attached to the surface of the flexible link for vibration suppression of it. This system is modeled as a nonlinear multi-input multi-output (MIMO) control systems whose inputs are two...

Nonlinear Control of a Linear Motion System

It is well-known that Bode’s gain/phase relation imposes limitations on the performance of a linear system. To circumvent these limitations, two examples from literature on nonlinear controllers, more precisely, a PID with nonlinear gain and a SPAN (split-path nonlinear) filter, are implemented on a motion system in order to improve the step response in comparison with a conventional linear PID...

An Energy Saving Valve for Refrigeration Equipment Mounting Rotary Compressor

Time-Invariant State Feedback Control Laws for a Special Form of Underactuated Nonlinear Systems Using Linear State Bisection

Linear state bisection is introduced as a new method to find time-invariant state feedback control laws for a special form of underactuated nonlinear systems. The specialty of the systems considered is that every unactuated state should be coupled with at least two directly actuated states. The basic idea is based on bisecting actuated states and using linear combinations with adjustable parame...

Potentials of Evolving Linear Models in Tracking Control Design for Nonlinear Variable Structure Systems

Evolving models have found applications in many real world systems. In this paper, potentials of the Evolving Linear Models (ELMs) in tracking control design for nonlinear variable structure systems are introduced. At first, an ELM is introduced as a dynamic single input, single output (SISO) linear model whose parameters as well as dynamic orders of input and output signals can change through ...