In order to research the dynamic characteristic of the scissor linear array deployable structure under the coupling action of clearance joints, the kinematic model of the deployable structure with clearance is established according to the principle of the motion between joint elements.The normal and tangential contact forces between joint elements are described using the Gonthier contact force model and LuGre friction model.In the sequel of this process, the contact forces between the bearing and the journal are converted to the mass centers of links connected by this clearance joint, and the converted contact force and additional torque were integrated to the generalized force in motion equations of the deployable structure, and then the effect of joint clearance is introduced to scissor-like-element.The simulation results show that there is no obvious change in the displacement and speed considering two clearance joints, and the acceleration and impact force appear the characteristic of high frequency oscillation;With the increase of the clearance size, the amplitude of acceleration response and constraint reaction force increases, and the collision time is prolonged;With respect to the clearance size, the joint at different position has different sensitivity, and the movement of a joint clearance will affect the movement of the other joint clearance, which shows that clearance joints in deployable structure have a strong dynamic interaction.In order to depict accurately the dynamic behavior of deployable structure, all the joints should be modeled as clearance joints.%为了研究剪式线性阵列可展结构在运动副间隙耦合作用下的动力学特性,通过含间隙转动副元素之间的运动规律建立了可展结构的运动学模型.基于Gonthier接触力模型以及LuGre摩擦模型分别计算了含间隙转动副元素之间的法向与切向接触力.进一步把该接触力转换到间隙运动副所连接杆件的质心处,并将其集成到剪式可展结构动力学模型的广义力中,从而将关节间隙效应引入到剪式机构中.仿真结果表明:考虑2个间隙铰链耦合时,加速度和碰撞力出现了高频振荡的特性;随着间隙尺寸的增加,加速度响应和约束反力的幅值增加,并且碰撞时间被延长;不同位置的铰链相对于间隙尺寸具有不同的敏感度,一个间隙铰链中的运动将影响其他间隙铰链中的运动,表明在可展结构中不同间隙铰链间会产生动力学相互耦合作用.为了更准确地描述可展结构的动力学行为,所有的铰链都应该被模拟为间隙铰链.
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