Highly Sensitive Polymer/Multiwalled Carbon Nanotubes Based Pressure and Strain Sensors for Robotic Applications

In the last decades, significant advances have been reached in the robotic field by the development and implementation of novel tactile sensors for robot hand and body attached sensors, in order to achieve high robot performance. Because of the unique and fascinating properties of polymer/carbon nanotubes (CNTs) nanocomposites, they were chosen for the design of highly sensitive and stable tactile sensors to detect pressure and strain. In this chapter we propose two sensor structures for robotic applications. Poly-Dimethylsiloxane/Multiwalled carbon nanotubes (MWCNTs) soft pressure sensors were prepared using solution processing method and molded in different shapes depending on the application requirements. The developed pressure sensors show promising piezocapacitive performance, very high sensitivity of 45%/N at low forces of 0–1 N and a wide pressure sensing a range of 0.5 Pa–570 kPa. These properties are essential for robotic applications like touch sensing, grasping and gait analysis. In the other part, conductive thermoplastic polyurethane (TPU)/MWCNTs filaments strain sensors were firstly made using an extrusion process. The sensors were subjected to strain loads. The results demonstrate excellent piezoresistive responses a gauge factor around 26 and stretchability more than 50% that was suitable for measuring finger bending.