直角切口柔性平行四杆机构的输出位移分析

 柔性铰链是目前被广泛用于微动机器人的主要部件之一.为了深入分析精密传动用柔性平行四杆机构的位移性能,利用材料力学弯曲变形理论的挠曲线近似微分方程,建立了计算直角切口柔性平行四杆机构输出位移的数学模型.设计了一个简单的柔性平行四杆机构模型,采用MATLAB 7.0软件对其进行理论计算,并利用商用软件ANSYS 10.0进行有限元分析.采用线切割的方法加工了一个样件,并进行了相关实验.最终结果表明：数学模型的理论值与有限元仿真值很接近,但与实际样件的实验值有一定的误差.通过误差分析,证实了存在这种误差的合理性,从而验证了所建数学模型具有较高的参考价值,可以作为柔性铰链平行四杆机构行程优化设计的指导理论.

Output displacement analysis of parallel four-bar mechanism with right-angle-notch flexure hinges

Flexible hinges are widely used as one of the essential components to micro-motion robotics. To analyze the output displacement performance of compliant parallel four-bar mechanism （CPFBM）, used as a precise transmission element, a mathematical model, which can be used to calculate the output displacement of CPFBM composed of right-angle-notch flexible hinges, was established by the approximate differential equation of the deflection curve based on the bending theory in strength of materials. A simple model of CPFBM was made and the theoretical value of the model was calculated by using the mathematic software MATLAB 7.0. Meanwhile, finite element analysis of the model was carried out by ANSYS 10.0. A sample piece was made by wire cutting for experimental purpose. The value of the sample piece obtained from the calculation of the mathematical model and from the finite element simulation met well, but the value from the experiment was obviously different from the theoretical value. Moreover, the sources of error were traced and existence of error was validated. In summary, the mathematical model proposed above has high value for reference to stroke displacement optimization design of CPFBM．