Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States.
Nano Lett. 2012 Dec 12;12(12):6302-8. doi: 10.1021/nl303405g. Epub 2012 Nov 26.
Various mechanisms are currently exploited to transduce a wide range of stimulating sources into mechanical motion. At the microscale, simultaneously high amplitude, high work output, and high speed in actuation are hindered by limitations of these actuation mechanisms. Here we demonstrate a set of microactuators fabricated by a simple microfabrication process, showing simultaneously high performance by these metrics, operated on the structural phase transition in vanadium dioxide responding to diverse stimuli of heat, electric current, and light. In both ambient and aqueous conditions, the actuators bend with exceedingly high displacement-to-length ratios up to 1 in the sub-100 μm length scale, work densities over 0.63 J/cm(3), and at frequencies up to 6 kHz. The functionalities of actuation can be further enriched with integrated designs of planar as well as three-dimensional geometries. Combining the superior performance, high durability, diversity in responsive stimuli, versatile working environments, and microscale manufacturability, these actuators offer potential applications in microelectromechanical systems, microfluidics, robotics, drug delivery, and artificial muscles.
目前有多种机制可将各种激励源转换为机械运动。在微观尺度上，由于这些致动机制的限制，同时实现高振幅、高输出功和高速致动是困难的。在这里，我们展示了一组通过简单的微制造工艺制造的微致动器，这些微致动器通过二氧化钒的结构相变来响应热、电流和光等各种刺激，在这些指标上均表现出了非常高的性能。在环境和水条件下，致动器在亚 100μm 长度范围内以极高的位移-长度比（高达 1）、超过 0.63J/cm3 的功密度和高达 6kHz 的频率弯曲，其致动功能可以通过平面和三维几何形状的集成设计进一步丰富。这些致动器结合了优越的性能、高耐用性、响应刺激的多样性、多种工作环境和微尺度制造能力，在微机电系统、微流控、机器人技术、药物输送和人造肌肉等领域具有潜在的应用前景。
