Topology Optimization Design Of The Wafer Handling Robot Arm

Wafer handing robot is one of the key equipments in the IC manufacturing process, which is used to transfer wafers form one position to another position between different working procedures, and it also has the function of localization. The working property of the wafer handing robot has direct effect on the productive efficiency and manufacture quality. The arm, as the vital part of the wafer handing robot, makes a great impact on the position accuracy of wafer handing robot. According to the demand of the high stability and high reliability during transferring wafer, it is important to propose an optimization design of arm for reducing undesirable vibration which will lead to an accident such as it drops the wafer during the transfer motion.Firstly, the current research and development of the wafer handing robot and structural topology optimization design are introduced at home and abroad in the paper, the designing thought by letting the topology optimization theory be applied to the arm structural design of the wafer handing robot is put forward. Based on the basic principle of the topology optimization theory, the methods for topology optimization design of continuum structures and solving algorithms are discussed, also the numerical instabilities in topology optimization are explained, the solving methods for the numerical instabilities are studied, and the formulas of the filtering method are mainly deduced.Then, based on the configuration and design principle of the wafer handing robot, the model of the wafer handing robot arm is established. The radial linear concertina motion of the wafer handing robot is analyzed, a type of mechanism that can implement the function is proposed, furthermore, the kinematics of the mechanism is analyzed. The structure of the wafer handing robot arm is designed, after that, finite element model of the arm is established, and also dynamic characteristic of the arm is analysed. Modal natural frequencies and modes of the wafer handing robot arm are obtained.Thirdly, aiming at the vibration of the wafer handing robot arm which caused in fast motion, a topology optimization method is proposed, and also the model of the arm is founded by the finite element method. The topology optimization design of the wafer handing robot arm is conducted in the software of ANSYS. The topology optimization result indicates that the structural flexibility of the arm is decreased, that is the structural stiffness is increased. At last, the novel structure of the wafer handing robot arm is modeled based on the topology optimization picture, and also dynamic characteristic of the arm is analyzed. The result shows that the low ordered natural frequencies of the arm are increased, while the vibration characteristics are improved. The research confirms the validity and correctness of structural topology optimization method in the design of wafer handing robot arm.