In this research a biologically inspired finger-like mechanism similar to human musculoskeletal system is developed based on Shape Memory Alloys (SMAs). SMA actuators are inspiring the design of a modular finger part with compact and compliant actuation. A three-segmented finger-like mechanism is designed and fabricated. This mechanism is composed of six bending Shape Memory Alloy (SMA) actuators. As a result, our finger mechanism is compact and compliant. The insider three SMA actuators are used for finger flexion while the outsider three SMA actuators are for extension. Each segment of this mechanism can be bent and/or extended independently by actuating a corresponding bending SMA actuator. Furthermore, full bending motion can be achieved by applying coordinated control of the three SMA actuators. Toward this goal a mathematical model of the SMA combined finger has been developed. The developed mathematical model is then used to design a proportional-derivative controller for control compliant actuation of the finger-mechanism. The performance of this mechanism has been experimentally evaluated. Our experimental results verify that the SMA-based finger module can achieve the desired postures similar to a human finger.

在这项研究中，基于形状记忆合金（SMA）开发了一种类似于人体肌肉骨骼系统的受生物启发的手指状机制。SMA促动器启发了紧凑，顺应性促动的模块化手指部件的设计。设计并制造了一种三段式手指状机构。该机构由六个弯曲形状记忆合金（SMA）执行器组成。结果，我们的手指机构紧凑而顺从。内侧三个SMA执行器用于手指屈伸，外侧三个SMA执行器用于伸展。通过致动相应的弯曲SMA致动器，可以独立地弯曲和/或伸展该机构的每个部分。此外，可以通过对三个SMA执行器进行协调控制来实现完全弯曲运动。为了达到这个目标，已经开发了SMA组合手指的数学模型。然后，将开发的数学模型用于设计比例微分控制器，以控制手指机构的顺应性致动。该机制的性能已通过实验评估。我们的实验结果验证了基于SMA的手指模块可以实现与人的手指类似的所需姿势。