Shape memory alloy tube actuators inherently enable internal fluidic cooling for a robotic finger under force control

Küçük Resim Yok

Tarih

2020

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

IOP Publishing Ltd

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

This paper presents the design, control and evaluation of a novel robotic finger actuated by shape memory alloy (SMA) tubes which intrinsically afford an internal conduit for fluidic cooling. The SMA tubes are thermomechanically programmed to flex the robotic finger when Joule heated. A superelastic SMA plate provides a spring return motion to extend the finger when cooling liquid is pumped through the internal channel of the SMA tube actuators. The mechanical design and nonlinear force controller are presented for this unique robotic finger. Sinusoidal and step response experiments demonstrate excellent error minimization when operated below the bandwidth which was empirically determined to be 6 rad s-1. Disturbance rejection experiments are also performed to demonstrate the potential to minimize externally applied forces. This method of internal liquid cooling of Joule heated SMA tubes simultaneously increases the system bandwidth and expands the potential uses of SMA actuators for robotic applications. The results show that this novel robotic finger is capable of precise force control and has a high strength to weight ratio. The finger can apply a force of 4.35 N and has a mass of 30 g. Implementing this design into wearable prosthetic devices could enable lightweight, high strength applications previously not achievable. © 2020 IOP Publishing Ltd.

Açıklama

Anahtar Kelimeler

Distributed parameter systems, Nonlinear control, Robotic finger, Shape memory alloy, Actuators, Bandwidth, Cooling, Disturbance rejection, Force control, Robotic arms, Robotics, Tubes (components), Error minimization, Internal liquids, Mechanical design, Prosthetic devices, Robotic applications, Shape memory alloy tube, Shape memory alloys(SMA), Step response experiment, Shape-memory alloy

Kaynak

Smart Materials and Structures

WoS Q Değeri

Scopus Q Değeri

Q1

Cilt

29

Sayı

11

Künye