11.1 Introduction11.2 Problem Statement11.2.1 Sensitivity Function11.2.2 Sensitivity Measures11.2.3 Insensitive H∞ Control with Controller Coefficient Variations11.3 Insensitive H∞ Controller Design11.3.1 Step 1: General Conditions for the Existence of Insensitive H∞ Controllers11.3.2 Step 2: Non-Fragile H∞ Controller Design with Interval-Bounded Controller Coefficient Variations