新型三维平移自由度Delta机构准零刚度隔振平台及特性

为实现空间三维低频隔振,提出一种具有空间三维平移自由度的新型Delta机构,并以此为基础,演绎成为具有负刚度特性的并联机构,然后并联正刚度的竖直弹簧,得到一种新型三自由度并联机构准零刚度隔振平台.通过建立隔振平台的静力学和动力学模型,分析其动平台在不同空间坐标位置时各自由度方向上的刚度特性和固有频率.结果表明:隔振平台...

A Novel 3-DOF Quasi-zero-stiffness Vibration Isolation Platform with Delta Mechanism and Its Characteristics

A novel Delta mechanism with three translational degrees of freedom in space is proposed to realize the spatial three-dimensional low-frequency vibration isolation.A parallel mechanism with negative stiffness is deduced from the Delta mechanism. Then a three-DOF parallel quasi-zero stiffness vibration isolation platform is constructed by connecting the parallel mechanism with a vertical spring with positive stiffness.The statics and dynamics models of the vibration isolation platform are established to analyze the stiffness characteristics and natural frequencies of the vibration isolation platform in different spatial coordinates.The result shows that the static characteristic of the vibration isolation platform is linear in the horizontal direction and is only related to the horizontal displacement. In the vertical direction，it has quasi-zero stiffness characteristic，which can obtain a lower natural frequency，and is only related to the vertical displacement. When the vibration isolation platform deviates from the equilibrium position，the zero-stiffness characteristic is no longer obvious. The vertical natural frequencies of the vibration isolation platform with the parallel mechanisms with and without negative stiffness were test. The test results show that the vibration isolation platform with the parallel mechanism with negative stiffness can greatly reduce the vertical natural frequency of the system.