A study of NiTi shape memory alloy springs and its application in a new robotic actuator

Author

Wen, M. ; Tu, G.F. ; Zong, Q.Y. ; Xie, C.X.

Author_Institution

Inst. of Mater. Sci., South China Univ. of Technol., Guangzhou, China

fYear

1994

fDate

5-9 Dec 1994

Firstpage

215

Lastpage

219

Abstract

A new actuator for a robotic hand, composed of two NiTi shape memory alloy (SMA) springs, is studied. First, the properties of NiTi SMA springs, including load-displacement dependences at various temperatures, resistance-temperature dependence, and recovery-temperature dependence are tested and analyzed. It is found that at a shear strain of 1.5% (a value below which NiTi alloy has a long cycling life) the load at 90°C is 8.5 times greater than at 10°, the transformation temperature A_f (austenite-finish temperature) increases with decreasing aging temperature and/or with increasing aging time. Next, a new actuator with two NiTi SMA springs for a robotic hand is studied. It is found that with this new actuation model, the serious limitations of heating and cooling speed which depend on heat transfer processes and make SMA motions slow, are greatly improved

Keywords

intelligent actuators; martensitic transformations; nickel alloys; recovery; robots; shape memory effects; titanium alloys; 10 to 90 C; NiTi; NiTi shape memory alloy springs; aging temperature; aging time; heat transfer processes; load-displacement dependences; recovery-temperature dependence; resistance-temperature dependence; robotic actuator; shear strain; Actuators; Aging; Capacitive sensors; Cooling; Heat transfer; Robots; Shape memory alloys; Springs; Temperature dependence; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Industrial Technology, 1994., Proceedings of the IEEE International Conference on

Conference_Location

Guangzhou

Print_ISBN

0-7803-1978-8

Type

conf

DOI

10.1109/ICIT.1994.467126

Filename

467126