Design and modeling of a compliant mechanism

Official URL: http://risc01.sabanciuniv.edu/record=b1169192 (Table of Contents)

Compliant mechanisms are widely used in high precision systems, because they provide high resolution, frictionless, smooth and continuous motion. These kinds of mechanisms are also cheaper than the other types of high precision mechanisms. The main idea of this kind of mechanism is that no additional joints are used for creating the motion, the deflection of the flexible elements are used to create the desired motion. In this thesis, a planar parallel compliant mechanism is designed. The mechanism is actuated from three ends by using piezo mike micromotors to create motion in XY plane. The mathematical model of the mechanism is derived by using Euler Bernoulli dynamic equation for the three beams on the mechanism. The separation of variables technique is used to solve the dynamic equations. Necessary transformations are calculated for defining the center position of the stage in terms of the deflections of the beam. The mathematical model is represented in state space form and it is simulated in MATLAB Simulink. The position results are compared with another simulation called COMET. The mathematical model is reduced to two input and two output system in order to make the XY position control of the mechanism by using PID control. Finally, the mechanism is manufactured by using laser cutting and water jet cutting techniques, open loop experiments of the mechanism are verified by actuating the piezo motors manually and by giving voltage signal.