Conventional electromechanical systems have some difficulty to adapt to the precise system, so there are many researches about smart actuators, which have great advantages in nano-position system and efficiency. However, they exhibit hysteresis nonlinearities that could affect to the precise control of actuators. So mathematical modeling of hysteresis is essential to apply smart materials to actuators. Hysteresis can be modeled mathematically for precise position control of smart actuator. Hysteresis is an analog phenomenon between input and output, and in classical Preisach model, hysteresis is presented by a summation of infinite sets of Preisach operator. The Preisach plane in actual system is expressed as a matrix. In other words, the Preisach model should be represented by a summation of finite sets of Preisach operator. All time-continuous characteristics of hysteresis phenomenon cannot be stored as data and used to model mathematically, therefore the mathematical model cannot avoid having error. By modification of Preisach model, the error can be reduced effectively.
