【作者】 刘延柱；

【Author】 LIU Yanzhu(Shanghai Jiao Tong University,Shanghai 200030,China)

【机构】 上海交通大学工程力学系；

【摘要】 本文建立摆长随位置改变的变长度摆的动力学模型,以模拟荡秋千运动或单杠振浪运动。根据文中给出的摆长控制规律列写动力学方程,并应用平均法和相平面法分析摆幅增大的变化过程。说明此类运动并非通常理解的参数振动,而应归类于自激振动。更多还原

【Abstract】 The problem of a pendulum,the length of which is varied according to the coordinates is discussed as a dynamical model of swing motion.The dynamical equations are established for a given control law of the variation of the length.The averaging method and the phase plane method are applied to analyze the increasing process of the swing amplitude.It is reasonable to classify the swing motion of the pendulum with variable length as the self-excited vibration,but not the parametric vibration.更多还原