Abstract
This paper deals with the problem of input-delayed robust state-feedback controller design for a class of semi-active seat suspension systems with parameter uncertainties and actuator time delays. A vertical vibration model of human body is employed and put together with the plant of the seat suspension system. The controller design is cast into a convex multi-objective optimization problem with linear matrix inequality (LMI) constraints by defining a Lyapunov functional and using the delay partitioning method. The usefulness and advantages of the proposed controller design methodology are demonstrated through a design example.