Design, modeling and characterization of a novel meso-scale SMA-actuated torsion actuator

作者：Sheng Jun^*; Desai Jaydev P

来源：Smart Materials and Structures, 2015, 24(10): 105005.

DOI：10.1088/0964-1726/24/10/105005

• torsion actuator
• shape memory alloy
• meso-scale actuator

This paper presents our work on design, modeling, and characterization of a novel shape memory alloy (SMA)-actuated torsion actuator for meso-scale robots. Development of a miniature torsion actuator is challenging, but it can enhance the agility and enlarge the workspace of meso-scale robots. This torsion actuator comprises a pair of antagonistic SMA torsion springs, which bi-directionally actuate the actuator by Joule heating and natural cooling. First, the mechanical design of the torsion actuator is presented, followed by the fabrication of SMA torsion springs. Then, we present the constitutive model of the SMA torsion spring with an analysis of its strain change, and derive a quasi-static model with the Coulomb friction torque for this torsion actuator. Finally, a series of characterization experiments are conducted on the SMA torsion spring and the torsion actuator prototype to determine the values of all model parameters. This work shows that the properties of the SMA-actuated torsion actuator can be appropriately characterized by experiments and the actuator is feasible for robotics applications.

• 出版日期2015-10