-- Introduction

posted Mar 15, 2011, 11:45 AM by Javad Taghia   [ updated Apr 24, 2011, 12:34 AM ]
In this introduction I am going to introduce soft actuators briefly. 
Certainly a soft-actuator is an actuator. The definition of actuator in wiki is ( http://en.wikipedia.org/wiki/Actuator) "An actuator is a mechanical device for moving or controlling a mechanism or system. It is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion.[1]". 

The specific characteristic of a soft-actuator is the adaptability. It means our actuator can be adapted in response to the applied potential in shape and dimension. 

In simple word, soft-actuators are similar to muscles. They are widely used in artificial muscles design. There are different technologies for realization of this kind of


There are two main categories for application of soft-actuators in medical application.

The first one is using soft-actuator as a muscle. Different polymers are used to

make artificial muscles. There are different researches and technologies in this regard such as  "Electro-active Polymer Artificial Muscle (EPAM) technology 

The second one is application of soft-actuators for rehabilitation purposes or robot arms or structures that deal with  or interact with human directly. Using pneumatic soft-actuators is considerable application of this type of soft-actuators.
I am going to focus on application and control strategies for rehabilitation applications in this introduction in future. For instance in the following paper manufacturing of a  pneumatic rubber artificial muscle is presented. In the abstract of this paper there is a good definition to this type of actuators.
"In the coming advanced age society, an innovative technology to assist the activities of daily living of elderly and  disabled people and the heavy work in nursing is desired. To develop such a technology, an actuator safe and friendly for human is required. It should be small, lightweight and has to provide a proper softness. We call such an actuator soft actuator. A pneumatic rubber artificial muscle is one of typical soft actuators, which is useful for the human assist 

In the following list I add some good resources about application of pneumatic soft-actuators in rehabilitation or in robotics.

1. Dynamic Pneumatic Actuator Model for a Model-Based Torque Controller.