IC封装等高速精密设备要求高速执行机构的机械结构在满足一定刚度下尽量降低惯性。基于等效静态载荷方法的优化方法是近来发展起来的柔性多体动力学优化设计的有效方法。针对高速机构的特点,对该优化方法做了一些改造。为了模拟运动关节影响,采用含有运动学自由度的准静态方法,对离散结构响应方程进行求解。为了考虑单元修改对惯性载荷的影响,将单元应变能与动能的比值作为单元修改的灵敏度。提出量纲一单元测度,能够综合反应该单元在所有离散点的重要性。所提方法应用于微电子封装摆杆式焊头摆臂的优化设计中,并将三种方法进行了比较,结果表明,含有运动学自由度的准静态分析能够反映机构运动副的影响,当速度非常高时,惯性比刚度对振动的影响更大。数值结果表明本文方法对高速机构的优化设计是有效的。
IC packaging device and other high-speed and high precision equipment require the mechanical structures of the high-speed actuator to minimize inertia under certain stiffness constraints.Optimization approach using equivalent static loads method is recently developed effective for optimal design of flexible multi-body dynamics.The optimization approach is modified according to the dynamic behavior characteristics of high-speed mechanism.The quasi-static analysis with kinetic degrees of freedom is used to solve equations of the discrete structure dynamiss with motion joints;The strain energy element sensitivity is changed by divided element kinetic energy,such that the changes of elements influent stiffness as well as inertial force of the structure;A non-dimensional measurement of elements is proposed to judge the important of an element at any situation The proposed method is used for optimal design of a die bonder of microelectronic packaging device,and three methods are compared,the results show that the quasi-static analysis with kinematic degrees of freedom is important for structures with motion joints.When the speed is very high,the inertia has greater impact of the vibration than the stiffness.Numerical results show that the optimal method of optimal structure design of high-speed mechanism to be effective.