Fig. 3.

Flexible microfluidic sensor that uses capacitance changes between liquid metal-filled microfluidic channels to measure normal force. (a) Device prototype, with conductive channels in top and bottom PDMS layers, separated by a middle layer of enclosed air channels. No solid electronics components are used. (b) Schematic of the top and bottom channel layers, forming a 5×5 array of sensing locations, called taxels, in the middle of the device. Image reproduced from Ref. 15.