Introducing micro-positioning experimental setup in mechanical engineering curriculum

The objective of this paper is to introduce an experimental setup to control vibration for educational purposes in undergraduate mechanical engineering program. The experimental set up presented in this paper is designed to allow the instructors to tailor and customize the experiments per the requirements of various mechanical courses. This vibration control is structured to study and control the vibration of a piezoelectric tube actuator, which is controlled by applying voltage difference across x and y axis. The piezoelectric tube was selected to be at the center of the experimental setup due to its importance in micro-positioning systems such as the Atomic Force Microscope (AFM). Due to the negative effect of high vibrations on the performance of AFM and other micro-positioning systems, vibration reduction of piezoelectric actuators is a very active research topic. Therefore, the introduction of piezoelectric actuators vibrations control experiment offers an excellent opportunity for students to learn more about the engineering problems and challenges associated with micro-positioning systems, which are not typically covered in classic mechanical engineering curriculum. The experimental setup introduced in this paper was used in a project in advanced dynamic systems and controls course. In this project, the students applied input shaping feedforward techniques to control the vibrations of piezoelectric tube when subjected to input step excitation. The success of the vibration reduction controllers was verified using the data acquired from two fiber optic displacement sensors. In addition, the experiment exposed the students to essential experimental principles such as calibration, data acquisition and sensor limitations.