旋转铰链是机械系统中应用最广泛的一种可动连接形式,针对旋转铰中的间隙对机械系统动力学行为的影响。采用非线性等效弹簧阻尼模型建立间隙旋转铰处的接触碰撞模型,并在模型中用非线性弹簧阻尼模型描述两物体的碰撞特性。然后,通过分段线性化处理给出非线性等效弹簧阻尼模型固有频率的解析表达式。结合理论分析和ADAMS动力学仿真,确定了接触模型固有频率的主要影响因素为等效弹簧刚度、间隙和转速,并给出了其影响规律。
The revolute joint is the most widely-used form of movable connection in mechanical systems. The clear- ance in revolute joint has an important affection to dynamic behavior of mechanical systems. In order to study this impact, the contact dynamics model is established in this paper, in which a nonlinear equivalent spring-damp mod- el is used to describe the characteristic of the two objects collide. The equation of nonlinear equivalent spring-damp model's natural frequency can be obtained by using the piecewise linearization method. The stiffness, clearance and rotational speed are the key impact factors of natural frequency. The effects of these impact factors on natural fre- quency are analyzed by using the theoretical analysis and ADAMS's dynamics simulation. Thus this paper provides a direction for the mechanism dynamic optimal design.