Modeling of the Piezoelectric-Driven Stick-Slip Actuators
In order to represent the presliding friction, the models reported in literatures, including Dahl model [Olsson, et al., 1998], Reset Integrator model [Haessig and Friedland 1991], LuGre model [Canudas de Wit et al., 1995] and Elastoplastic model [Dupont et al., 2002] were reviewed and examined; and the LuGre model was chosen to be used because of its efficiency and simple formulation. On the other hand, a linear second order dynamic system model was employed to represent the combination of a PEA and its driven mechanism. On the basis of the pre-sliding friction model and the linearized PEA dynamics model, a model representative of the end-effector displacement of the PDSS actuator model was developed.
In order to validate experimentally the developed PDSS model, a displacement measuring and data acquisition experiment system was established and a prototype was developed based on dSPACE and Simulink. On the prototyped actuator, two experiments were designed and conducted to identify the parameters involved in the model. One experiment is for the determination of the parameters of the second order system for the dynamics of the combination of a PEA and its driven mechanism; and other one is for the determination of the parameters of the chosen friction model. The identified parameters were then employed in the developed PDSS model to simulate the displacements and the results were compared with the experimental results that were obtained under the same operating conditions as the simulation. The comparison suggests that the model developed in this study is promising for the end-effector displacement of the PDSS actuator.
Advisor:Daniel Chen; Reza Fotouhi; Chris Zhang
School:University of Saskatchewan
School Location:Canada - Saskatchewan
Source Type:Master's Thesis
Keywords:dynamics modeling stick slip motion presliding friction piezoelectric actuator ultraprecision positioning
Date of Publication:11/23/2007