A Flexible Tactile Sensor for Three-dimensional Force Detection Based on Piezoelectric Sensing

A flexible tactile sensor was proposed to measure the three-dimensional forces. The sensor consisted of a bump structure, top and bottom electrodes, a piezoelectric sensitive layer and a substrate layer. The top and the bottom electrodes were prepared by lift-off process. When a three-dimensional force was applied, the bottom four electrodes under the bump structure would collect different charge signals, which can be detected by the different electric current variations. In the experiments, when the forces range from 0 to 10N with different angles were applied to the bump structure, the sensor can measure forces with a best non-linearity of 1.89%. This proposed tactile sensor could be used in the intelligent robotics to measure multi-dimensional force.