Abstract: A support for an elongated piezoelectric pressure sensor, which is general cylindrical in shape is mounted on a hollow support member that has a thickness and strength selected to meet desired conditions. The elongated piezoelectric pressure sensor is wound in a helical depression on the exterior of the support member, and the support member in turn is filled with a potting material having a bulk modulus of elasticity selected to provide a sufficient flexibility so that the elongated piezoelectric sensing element generates signals that have a desired sign characteristic and improved acoustic response.

Abstract: A pressure sensing transducer comprises a central region which comprises a potting material and which is surrounded by a helix of piezo electric coaxial cable. The transducer includes a barrier that suppresses transmission of external pressure variations to the central region. In addition, the overall radial stiffness of the potting material and barrier is sufficiently low that the electrical signal generated by the coaxial cable have a d.sub.31 polarity (corresponding to axial stretching and contracting of the cable).

Abstract: An impact sensing arrangement comprises a pair of bodies that are separated from each other and arranged so that an impact on one of the bodies will cause it to move toward the other body, and an elongate piezoelectric pressure sensing element that is positioned between the bodies, the pressure sensing element being mechanically coupled to each of the bodies over at least one quarter and preferably at least two thirds, the width of the sensing element.The arrangement is particularly suitable for use in an ordance projectile in which case the sensing element 10 may extend in a loop around the projectile between the nose 3 and body 2 of the projectile.