A pneumatic actuator having a flexible plate, the flexible plate being made of a rigid flexible material. The pneumatic actuator further includes at least two elongate, flexible but poorly extensible pneumatic pressure ducts that are disposed side by side and are in parts connected to the flexible plate to which they are secured and on which they are arranged in such a manner that, when the pressure ducts are pressurized with compressed gas, tangential forces are generated parallel to the flexible plate causing said flexible plate to bend.