Abstract: A capacitive pressure-sensitive and displacement-sensitive sensor apparatus and method in which first electrode means comprising a thin resilient conductive inclined or arcuate plastic sheet having a plurality of resilient projections protruding from the inner surface of the sheet and with said projections pressure-deformable by application of pressure thereat from the outer surface of the sheet cooperates with a second relatively flat electrode facing and coextensive with the projections and separated from the same by a thin dielectric layer therebetween, the first electrode extending inclinedly or arcuately over the second electrode such that when force is applied to the resilient first electrode along said outer surface thereof, as by a portion of means such as a keyboard key contacting the same, it approaches the second electrode and dielectric layer through air in a fashion which causes the resilient deformable projections along the inclined or arcuate inner surface thereof to contact said dielectric lay

Abstract: A novel capacitive pressure-sensitive sensing technique and apparatus wherein an elastomeric conductive electrode carrying a two-dimensional array of projections is pressure-deformed against a fixed coextensive cooperative electrode to generate signals, such as tones and sounds in the application to musical instruments, or visual representations, corresponding to the dynamic pressures applied over the two-dimensional surface. A novel drum-like and other musical instruments embodying such novel capacitive sensing techniques and the like are described.