半轮型柔性铰链的结构设计和分析

Structural Design and Analysis of Half-cartwheel Flexure Hinge

柔性铰链由于具有无间隙、无摩擦和易于一体化设计等诸多优点,而被广泛应用于精密操作、机器人、微纳定位等需要超精密高速运动的领域。面向高速高加速度双侧驱动系统,针对运动系统的整体高刚度和局部相对低刚度特性,设计了一种具有平动高刚度和扭转低刚度的半轮型柔性铰链。基于旋量变换理论,以半轮型柔性铰链中柔性单元的尺寸和位置角度作为设计几何参数,推导了铰链的六自由度刚度矩阵模型,并综合分析了各项设计几何参数对铰链的各向刚度、相对刚度以及转动误差的影响,并以整体平动高刚度和扭转低刚度为设计约束条件,讨论铰链结构参数的选取。结果表明:该设计方法更为简洁、快捷,从而为柔性铰链的设计和应用提供一定的依据。

Flexure hinges are widely used in fields that require ultra-precision high-speed motion,such as precision operations,robots,and micro-nano positioning,due to their many advantages,such as no gap,no friction,and easy integration.In order to solve the problem that the simultaneous consideration of high translation stiffness and low twist stiffness in the H-drive,a half-cartwheel flexure hinge was designed according to the required stiffness requirements.Based on the screw theory,the six-degree-of-freedom stiffness matrix model of the flexure hinge was deduced with the size and position angle of the flexible element in the half-wheel flexure hinge as the design geometric parameters.The effects of various design geometric parameters on the stiffness,off-axis/axis stiffness ratio of the flexure hinge and motion precision were comprehensively analyzed.Finally,taking the simultaneous consideration of high translation stiffness and low twist stiffness as the design constraints,the selection of hinge structure parameters was discussed.The results show that the design method proposed is simpler and faster,thus providing a certain basis for the design and application of flexure hinges.