ABSTRACT
In a feedback control system, it is important to determine where the sensors should be placed in the control system and which state variables can be detected. During closed-loop control, the object is exactly on the right position when its position error in a feedback loop is zero, but the plant dynamics and disturbances are in the control loop. Controlling the ambient conditions such as temperature and active damping systems are commonly used to stabilize or remove the effects since disturbances are the main issue in the design of the system. The importance of modeling has been well-recognized, such as the model-based development approach, but modeling is mainly carried out on the plant or controlled object. To improve the positioning accuracies, much effort has been devoted to applying various control theories in high-performance mechatronic systems. In order to enhance the control performances of mechatronic systems, various approaches other than merely increasing the positioning speeds and accuracies are also important.
