新型SMA纤维驱动器的结构、建模与仿真

摘要

Shape memory alloy are a class of materials capable of producing a significant force or displacement in response to a thermal control input. Being simple, light, and powerful, shape memory alloy actuators hold much promise for the future of lightweight robotics and miniaturization. As classic obstacles such as further miniaturization, speed of operation and limited strain are overcome, their widespread application may become a reality, and the field of robotics will benefit from a truly novel actuator.rn　　In this paper, a novel shape memory alloy (SMA) actuator consisting of a number of thin NiTi fibers woven in a counter rotating helical pattern around supporting disks was first described. The actuator overcame the main mechanical drawback of shape memory alloys——limited strain. At the same time, a simulator was developed to predict characteristics of the given actuator, or to define its geometry under specifications such as force, speed, stroke and size. Finally, experimental and simulation results in the time domain were discussed.%介绍了一种新型的形状记忆合金（SMA）纤维驱动器，这一驱动器由预压缩弹簧连接的若干圆盘构成,圆盘周围对称编织多根SMA纤维。依靠SMA纤维的相变回复力与压缩弹簧的弹力完成驱动器的往复动作。这一结构有效地克服了SMA的主要缺点：形变较小，使驱动器的力与位移之间的转换更加高效。还给出了一种仿真模型，可以评价一给定驱动器的特性，同时也可在给定驱动器的力、位移、速度等条件下决定该驱动器的几何结构。最后，对单个驱动器与差动排列的驱动器对的实验和仿真结果进行了分析。