Flexible Pressure Sensor for Robotic Touch

Robotic touch sensors need to satisfy both accurately sense on the force and precisely position of the force. In this paper, PVDF-TrFE piezoelectric film was fabricated on a flexible circuit board through an in-situ polarization method. The crystallinity of PVDF is improved by a small amount of hydroxyapatite doping, which is beneficial to the conversion of β crystal form, and thus increases the piezoelectric coefficients of PVDF. With the increased piezoelectric coefficient, the electrical response precision of PVDF to force is improved, and makes the PVDF-based pressure sensing device more sensible. The flexible PVDF piezoelectric sensor is fabricated by using a flexible PCB, which can not only realize three-dimensional sensing of the force level, but also locate the position of the force, so that it can be applied to the tactile sensing of the robot.