Intelligent FMA using flexible displacement sensor with paste injection

Recently, a variety of soft actuators have been developed. However, applicable sensors such as potentiometers and optical encoders generally have high stiffness and when they are used in a soft actuator, the actuator loses its compliance. To solve this problem, a flexible displacement sensor has been developed. This sensor was fabricated by depositing a conductive paste onto a rubber seat. Paste injection was utilized in the fabrication process of the sensor, and precise control of thickness, width and pattern of the conductive film and deposition onto a curved surface was realized by this system. Firstly, an experiment on a flat-type flexible displacement sensor was conducted to evaluate and improve the sensor. The experimental results showed sufficient linearity and detecting range. Then, an intelligent FMA (Flexible Microactuator) was fabricated by depositing the conductive paste onto the surface of an FMA. A servo control system for the intelligent FMA was set up, and high positioning accuracy was confirmed by a servo driving experiment.�