Figure 5
From: Direct-current generators based on conductive polymers for self-powered flexible devices
Strain sensing array based on direct-current generators. (a) Fabrication process of the array of direct-current generators. (b) Photo images of direct-current generator array conformally attached on a tennis ball. (c) Mapping of voltage output of every unit in the array. (d) Mapping of pressure extracted from the measured voltages.
