Actuators: Modeling and Analysis

In robotics, three large families of actuators are mainly used: electric, hydraulic and pneumatic actuators. The conversion of energy into motion is a key point of actuators. It is possible that smart actuators can be achieved with self-calibration, information processing, communications and control systems or servos. Actuators are chosen according to the tasks achieved and required performance. When great precision, important torque performance, significant velocities and acceleration are desirable, people resort to electric actuators or direct current motors. This chapter presents the modeling of the dynamic behavior of rotating DC machines. The dynamic model of the pneumatic system is composed of two stages: a dynamic stage that takes the mechanical aspects into consideration and a second stage corresponding to the pneumatic actuators. The hydraulic actuator modeling is based on the study of the flux stages provided by a fixed pressure.