Roland Longchamp

À propos
Confidentialité
Mentions légales

Graph Chatbot

Publications associées (32)

Gain-Scheduled Controller Design by Linear Programming

Roland Longchamp, Marc Kunze, Alireza Karimi

A linear programming approach is proposed to tune fixed-order linearly parameterized gain-scheduled controllers for stable SISO linear parameter varying (LPV) plants. The method is based on the shaping of the open-loop transfer functions in the Nyquist dia ...

2007

Robust Control of Polytopic Systems by Convex Optimization

Roland Longchamp, Alireza Karimi, Hamid Khatibi

Robust control synthesis of linear time-invariant SISO polytopic systems is investigated using the polynomial approach. A convex set of all stabilizing controllers for a polytopic system is given over an infinite-dimensional space. A finite-dimensional app ...

2007

Robust PID Controller Design by Linear Programming

Roland Longchamp, Marc Kunze, Alireza Karimi

A linear programming approach is proposed to tune fixed-order linearly parameterized controllers for stable LTI plants. The method is based on the shaping of the open-loop transfer function in the Nyquist diagram. A lower bound on the crossover frequency a ...

2006

Friction Modeling of a High-Precision Positioning System

Alain Curnier, Roland Longchamp, Marc Kunze, Alireza Karimi, Sébastien Thiery

Friction modeling of a high-precision positioning system using linear permanent magnet synchronous motors is investigated. The friction force is measured precisely by some specific experiments to eliminate the parasitic ripple force. The experimental data ...

2006

Data-Driven Controller Tuning Using Frequency Domain Specifications

Roland Longchamp, Daniel Garcia, Alireza Karimi

A model-free PID controller tuning approach is presented in this paper. The method can handle different stability and performance indicators in the frequency domain. The phase margin, gain margin, crossover frequency and more advanced indicators which are ...

2006

A Comparison of Iterative Learning Control Algorithms with application to a Linear Motor System

Roland Longchamp, Alireza Karimi, Mark Edward John Butcher

Iterative Learning Control (ILC) is a technique used to improve the tracking performance of systems carrying out repetitive tasks, which are affected by deterministic disturbances. The achievable performance is greatly degraded, however, when non-repeating ...

2006

PID controller design with constraints on sensitivity functions using loop slope adjustment

Roland Longchamp, Daniel Garcia, Alireza Karimi

This paper presents a PID controller design method for stable minimum- phase systems. The approach is similar to the one proposed in the so-called modified Ziegler- Nichols method, where only one point on the frequency response of the plant is measured and ...

2006

Interactive applications in a mandatory control course

Yves Henri Philippe Piguet, Roland Longchamp

This paper describes how a mandatory control course is enhanced with interactive applications. Basic concepts of automatic control, different ways to assess performance and robustness of a controlled system, and limits of closed- loop systems are illustrat ...

2006

PID Controller Design with Specifications on the Infinity-Norm of Sensitivity Functions

Roland Longchamp, Daniel Garcia, Alireza Karimi

A controller design method using a frequency criterion is proposed in this paper. The frequency criterion is defined as the weighted sum of squared errors between the specified and computed values of the design parameters. These are the infinity-norm of th ...

2005

PID Controller Design for Multivariable Systems Using Gershgorin Bands

Roland Longchamp, Daniel Garcia, Alireza Karimi

A method to design decentralized PID controllers for MIMO systems is presented in this paper. Each loop is designed separately, but the Gershgorin bands are considered to take interactions into account. The method uses different design parameters: The infi ...

2005

Model-Free Precompensator and Feedforward Tuning Based on the Correlation Approach

Roland Longchamp, Alireza Karimi, Mark Edward John Butcher

High performance output tracking can be achieved by precompensator or feedforward controllers based on the inverse of the closed-loop system or the plant model. However, it has been shown that these inverse controllers can affect adversely the tracking per ...

2005

Commande sous-optimale adaptative de systèmes non linéaires

Roland Longchamp

EPFL1978

Page 2 sur 2