Abstract: An apparatus as provided for measuring acceleration of a person's head or other object. The apparatus comprises a sensor for sensing acceleration and a controller for controlling recording of data resulting from the sensed acceleration due to an explosive force. The controller is adapted to determine whether or not to enable recording of the data based on the sensed acceleration. A data receiver is provided to receive the sensed acceleration data from the sensing means, and requires electrical power to enable data to be received thereby. The controller controls electrical power to the receiver so that if the sensed acceleration reaches or exceeds a predetermined value, electrical power to the data receiver is enabled. The recorded acceleration data may be used for injury analysis.

Abstract: A method of calibrating a data recording unit for measuring head acceleration, including the steps of providing a data recording unit mounted to a head protector, mounting the head protector on a support, subjecting the head protector and support to a force or pressure, measuring acceleration of the head protector resulting from the force or pressure, measuring acceleration of the support resulting from the force or pressure, and determining a relationship between the measured acceleration of the head protector and of the support.

Abstract: An apparatus for recording data indicative of acceleration of a part of a person's body or other object, including first memory means for receiving acceleration data from an acceleration sensor, second memory means operatively coupled to the first memory means for receiving data from the first memory means, and a data transfer controller for controlling the transfer of data from the first memory means to the second memory means based on the acceleration data.

Abstract: An apparatus as provided for measuring acceleration of a person's head or other object. The apparatus comprises a sensor for sensing acceleration and a controller for controlling recording of data resulting from the sensed acceleration due to an explosive force. The controller is adapted to determine whether or not to enable recording of the data based on the sensed acceleration. A data receiver is provided to receive the sensed acceleration data from the sensing means, and requires electrical power to enable data to be received thereby. The controller controls electrical power to the receiver so that if the sensed acceleration reaches or exceeds a predetermined value, electrical power to the data receiver is enabled. The recorded acceleration data may be used for injury analysis.

Abstract: A tri-axial vibration isolation device having: a passive isolation assembly including a first frame, a plurality of passive lateral isolators supporting the support frame on the base, and a plurality of passive vertical isolators; and an actuator assembly including a second frame, a vertical actuator arranged between the load and the second frame, and a plurality of lateral actuators arranged between the second frame and the passive vertical isolators. The actuators can be piezoelectric elements that change their thickness in response to an electrical signal. The lateral actuators are arranged in oppositely poled pairs. An accelerometer or other sensor provides information to a controller that controls the actuators.

Abstract: A thin, lightweight electroacoustic actuator device covering a large surface area providing a high piston-like output over the frequency range of from at least 30 to in excess of 500 Hz comprising a stiff, lightweight face plate; a backing structure disposed below the face plate; at least one driver structure disposed between the face plate and the backing structure; and flexible structure flexibly connecting the at least one driver to the face plate.

Abstract: A thin, lightweight electroacoustic actuator device covering a large surface area providing a high piston-like output over the frequency range of from at least 30 to in excess of 500 Hz comprising a stiff, lightweight face plate; a backing structure disposed below the face plate; at least one driver structure disposed between the face plate and the backing structure; and flexible structure flexibly connecting the at least one driver to the face plate.