Abstract: A method of processing a raw acceleration signal, measured by an accelerometer-based compression monitor, to produce an accurate and precise estimated actual depth of chest compressions. The raw acceleration signal is filtered during integration and then a moving average of past starting points estimates the actual current starting point. An estimated actual peak of the compression is then determined in a similar fashion. The estimated actual starting point is subtracted from the estimated actual peak to calculate the estimated actual depth of chest compressions. In addition, one or more reference sensors (such as an ECG noise sensor) may be used to help establish the starting points of compressions. The reference sensors may be used, either alone or in combination with other signal processing techniques, to enhance the accuracy and precision of the estimated actual depth of compressions.

Abstract: Accelerometers as disclosed herein include a proof mass assembly and an accelerometer support. In some examples, a combined height and a combined coefficient of thermal expansion (CTE) of the materials of the accelerometer support is configured to substantially match a CTE of material of the non-moving member with a height substantially similar to the combined height of the accelerometer support. In some examples, the accelerometer support is configured to connect to a center raised pad of the proof mass assembly and maintain a capacitance gap between a capacitance plate on a proof mass of the proof mass assembly and a portion of the non-moving member.

Abstract: A micromechanical acceleration sensor is described which includes a substrate and a seismic mass which is movably situated with respect to the substrate in a detection direction. The micromechanical sensor includes at least one damping device for damping motions of the seismic mass perpendicular to the detection direction.

Abstract: An inertial sensor has an interior filled with a relatively low viscosity fill gas. To that end, the inertial sensor has a housing forming the noted interior, and a movable component within the interior. The inertial sensor also has the noted fill gas within the interior. The fill gas has a viscosity that is less than the viscosity of nitrogen under like conditions. For example, when subjected to the same temperatures and pressures, the fill gas has a viscosity that is less than the viscosity of nitrogen.

Abstract: A high-frequency oscillation circuit incorporates a crystal resonator having a natural oscillation frequency in a high-frequency area within a closed circuit including one or more logic elements. Therefore, this circuit copes with an oscillation frequency of 1 MHz to 2 GHz or more in basic oscillation frequency of a crystal resonator and it oscillates with stability at the basic oscillation frequency of the crystal resonator.

Abstract: A damping gyrometer comprised of at least two and preferably four rotating paddles attached to a common central elevated low-friction pivot point via rising radial arms. A stand with a concave glass element provides a low-friction support as a pivot point seat for the pivot point. All elements of the apparatus are non-conductive. Once set into motion, the only force acting on the gyrometer are the pivot point friction and the damping effects of the medium in which it spins. A laser beam and photodetector (or alternatively a laser displacement sensor), along with customized software algorithms are used to measure the rotational rate and, hence, the deceleration rate of the apparatus which can then be used to determine properties of the medium in which it spins, including changes in density, pressure, and temperature. The measurement can also be directly related to the electron density in the case of weakly ionized gases.