制御工学ブログ / Control Engineering Blog

制御工学の基礎から専門まで、動画・MATLABコード付きで解説。20年以上の研究経験をもつ大学教員が運営。Control engineering tutorials, research articles, and MATLAB code by a university researcher. Topics: LMIs, state estimation, model error compensator, multirate systems, observer design.

Welcome to the Control Engineering Blog / 制御工学ブログへようこそ

Guide to all articles: Control engineering, Control theory, Research, MATLAB code, and Video lectures. 制御工学ブログの全記事ガイドです:制御工学の記事へのリンク,論文執筆・プレゼン記事もあります。

制御教育インタラクティブ教材

制御教育のためのインタラクティブ教材を作成しました。アダプティブクルーズコントロールや倒立振子のアニメーションを実行できます。スライドバーを動かして実行すれば、状況ごとの応答を確認できます。

SCI 2026 の参加報告

SCI 2026 が名古屋で開催され参加しています。 5/23に熊本→小牧(名古屋)に移動しました。FDAに初めて乗りました。 金色の飛行機? pic.twitter.com/7uP31GNnDA— Hiroshi Okajima (@control_eng_ch) 2026年5月23日 久々に名古屋に来たので、とりあえず、前…

From Noise to Knowledge: System Identification with Systematic Polytope Construction via Cyclic Reformulation

A system identification framework that turns measurement noise into a structured uncertainty description. Cyclic reformulation with period N is applied to LTI systems to construct polytopes from a single experiment, then used for robust H∞…

LMI Optimization Based Multirate Steady-State Kalman Filter Design

An LMI-based design framework for multirate steady-state Kalman filters using cyclic reformulation. Addresses the semidefinite measurement noise covariance in systems with sensors at different sampling rates (e.g., GPS at 1 Hz + wheel spee…

Kernel-Based System Identification: Regularized Impulse Response Estimation with Stable Spline Kernels

A tutorial on kernel-based regularized system identification. Explains stable spline, tuned-correlated, and diagonal-correlated kernels, hyperparameter tuning via empirical Bayes, and MATLAB implementation with impulseest.

Model-Based Compensation Methods in Control Engineering: IMC, DOB, 2-DOF, and MEC

Compare IMC, Smith Predictor, Disturbance Observer, 2-DOF control, and Model Error Compensator (MEC). Structural comparison, selection guidelines, and connections to robust control engineering.

State Feedback Control and State-Space Design: A Comprehensive Guide

A comprehensive tutorial on state feedback control and state-space design for control systems. Covers pole placement, LQR optimal regulators, integral-type servo systems, LMI-based design, observer-based feedback with the separation princi…

Two-Degree-of-Freedom Control and the Model Error Compensator: Origin and Extensions

The 2-DOF conditional feedback structure is the structural origin of MEC. Setting T = P_M yields MEC, which is equivalent to 2-DOF control for linear systems with feedforward input. MEC extends further to non-minimum-phase and nonlinear sy…

Internal Model Control (IMC) and MEC: Structural Comparison of Model-Based Compensation Methods

Structural comparison of Internal Model Control (IMC) and Model Error Compensator (MEC). Both use the plant-model output difference, but IMC designs the controller while MEC adds robustness to existing systems.

MEC Research by Other Groups

A survey of Model Error Compensator (MEC) research by independent groups worldwide. Covers applications to quadcopters, teleoperation, underwater robots, power electronics, data-driven tuning with FRIT and Smart MBD, and theoretical analys…

MEC for Nonlinear Systems: Robust Feedback Linearization via Output Feedback

Apply the Model Error Compensator (MEC) to nonlinear systems for robust feedback linearization. Unlike standard feedback linearization, MEC does not require exact model knowledge or full state measurement. The output-feedback structure ach…

MEC for Non-Minimum Phase Systems: Parallel Feedforward Compensator Approach

How to apply the Model Error Compensator (MEC) to non-minimum phase systems using a parallel feedforward compensator. Non-minimum phase plants have unstable zeros that prevent standard high-gain compensation. The PFC approach resolves this…

MEC + PID Control: Adding Robustness to the Most Widely Used Controller

Learn how to add robustness to existing PID control systems using the Model Error Compensator (MEC). MEC is a simple add-on compensator that suppresses the effect of model uncertainty and parameter variations without modifying the PID cont…

Classical Parametric System Identification: ARX, ARMAX, and the Prediction Error Method

A tutorial on classical parametric system identification. Explains ARX, ARMAX, Output-Error, and Box-Jenkins model structures, the prediction error method (PEM) for parameter estimation, model order selection, and MATLAB implementation. In…