| The high-speed and high-precision positioning system is one of the key components of integrated chip(IC) wire bonder, and the research on its structure design and control methodology has important academic and application values. To improve the efficiency and quality of IC bonding, this dissertation studies on the structure dynamic design theory, the motion control strategies and prototype manufacturing technology for 2-DOF high-speed and high-precision positioning table, ultrasonic transducer and bond head. The following contributions have been made:The dynamic design methodology of high-speed and high-precision positioning system is proposed based on electromechanical co-simulation method. By use of ANSYS, MSC.ADAMS and MATLAB/SIMULINK software, the rigid-flexible coupled mechanical solid model and the controller model of the positioning system are established, and the characteristics of the mechanical and control system of the XY positioning table are simulated. The influences of the preloaded spring to the characteristics of the positioning system are investigated, and the matching law of the spring stiffness and preload is achieved. Finally, the spring stiffness and preload are determined.Considering the characteristics of the direct drive by voice coil motor(VCM), the control strategy of the 2-DOF high-speed and high-precision positioning table is presented. Firstly, the open-loop models of the control system for X-axis and Y-axis tables are obtained through system identification method. On this basis, Proportion Integration Differentiation(PID) controller, PID controller with friction and feedforward compensators, proportional switching sliding mode controller(SMC), and SMC based on exponential reaching law are designed to control the X-axis table, respectively. Electromechanical co-simulation and experiment results show that the motion overshoot and settling time are reduced using the SMC based on exponential reaching law, and this controller shows strong robustness in the face of disturbances. Thus it is very suitable for the motion control of such kinds of positioning table. The experiment results and simulation results are in good agreement, which confirms the validity and feasibility of the dynamic design methodology for high-speed and high-precision positioning system based on electromechanical co-simulation method. The structure design method for high-frequency ultrasonic transducer used in IC wire bonding is developed on the basis of the electromechanical equivalent theory, finite element analysis(FEA) and modular design concept. With the aid of this method, the modal concentration problems of high-frequency transducers can be solved, meanwhile avoiding the process of repeated modelings and calculations. A 100 kHz ultrasonic transducer has been designed, and the law of ultrasonic energy transmission in spatial domain, time domain, and frequency domain are discussed, respectively. The experiment results by impedance analyzer and laser Doppler vibrometer measurements show that the transducer has good vibration characteristics. The experiment results prove remarkable resemblance with simulation analysis results through FEA.A novel rotary VCM direct-drive bond head mechanism is presented and manufactured. Considering the dynamic characteristics of the bond head, a three closed-loop PID controller with friction compensator and notch filter is designed, and the motion control system is established. The experiment results show that the motion characteristics of the bond head can satisfy the requirements of IC wire bonding.The above research achievements enrich the design theory of precision positioning system used in IC wire bonding, and they have great significances on promoting the development of microelectronics packaging equipments.
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