Flexible shape memory alloy actuators for soft robotics: Modelling and control

Dorin-Sabin Copaci,Dolores Blanco,Luis Moreno,Alejandro Martin-Clemente

doi:10.1177/1729881419886747

Dorin-Sabin Copaci, Dolores Blanco + Show 2 more

Open Access

https://doi.org/10.1177/1729881419886747

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Abstract

One of the limitations in the development of really soft robotic devices is the development of soft actuators. In recent years, our research group has developed a new flexible shape memory alloy actuator that provides more freedom of movements and a better integration in wearable robots, especially in soft wearable robots. Shape memory alloy wires present characteristics such as force/weight ratio, low weight, and noiseless actuation, which make them an ideal choice in these types of applications. However, the control strategy must take into account its complex dynamics due to thermal phase transformation. Different control approaches based on complex non-linear models and other model-free control methods have been tested on real systems. Some exoskeleton prototypes have been developed, which demonstrate the utility of this actuator and the advantages offered by these flexible actuators to improve the comfort and adaptability of exoskeletons.

Highlights

The use of the so-called smart materials in various areas of engineering has experienced great growth in recent years
We summarise the research carried out from the last few years in our research group relative to the modelling and control of shape memory alloys (SMAs)-based actuators
To use actuators based on SMAs in robotic applications, it is necessary to improve the mechanical design of the actuators and the controller systems

Summary

Introduction

The use of the so-called smart materials in various areas of engineering has experienced great growth in recent years. Keywords SMA materials, flexible actuator, modelling, control, soft robotics, wearable robots To extend the use of these materials as soft actuators, it is essential to develop an appropriate mechanical design and suitable control strategies to improve operational frequency, bandwidth and the durability and reliability of SMA actuators.

Results

Conclusion