A sensing device for measuring pressure, more particularly, a stretchable bidirectional capacitive pressure sensor 20 is disclosed. The sensor comprises a first elastomeric sheet 22 with a series of conductor lines 221 located on or in the first elastomeric sheet, a second elastomeric sheet 28 with a series of conductor lines 261 located on or in the second elastomeric sheet; and a microstructure comprising a plurality of elastomeric pillars 241 disposed between the elastomeric sheets; wherein the The microstructure is bonded to both the first and second elastomeric sheets to allow the bidirectional sensor to register positive and negative pressure by the movement of the first and second elastomeric sheets. A further aspect of the invention discloses a method of collecting data related to fluid flow over an object by using a two-dimensional capacitive pressure sensor.