An inertial sensor module includes: a first inertial sensor having a first axis as a detection axis; and a second inertial sensor having the first axis, a second axis, and a third axis as detection axes, in which the first inertial sensor and the second inertial sensor are separated from each other, and detection accuracy of the first inertial sensor is higher than detection accuracy of the second inertial sensor.

An angular acceleration detection device includes a rotating weight, a fixed portion, a support beam, and a detection portion. The rotating weight is rotatable about a Z-axis with respect to the fixed portion by action of an inertial force generated by an angular acceleration about the Z-axis. The fixed portion is disposed at a position spaced from the rotating weight. The support beam is disposed in an X-Y plane between the fixed portion and the rotating weight, the support beam elastically supporting the rotating weight with respect to the fixed portion. The detection portion outputs a detection signal corresponding to stress generated in the support beam. A gravity center position of the rotating weight is aligned with the support beam when viewed in a Z-axis direction.

An accelerometer arrangement and method are described for determining accelerations of an inground tool. First and second triaxial accelerometers are supported such that a normal sensing axis of the first triaxial accelerometer is at least generally orthogonal to the normal sensing axis of the second triaxial accelerometer for determining the accelerations along the three orthogonal axes based on a combination of sensing axis outputs from one or both of the triaxial accelerometers. A weaker sensing axis of one triaxial accelerometer can be supported at least approximately normal to a weaker sensing axis of another triaxial accelerometer such that the weaker axes are not used. The triaxial accelerometers can be supported such that one axis of one accelerometer can be redundant with respect to another axis of another accelerometer. One triaxial accelerometer can be mounted on a tilted plane with respect to another triaxial accelerometer.

A sensor module includes an X-axis angular velocity sensor device that outputs digital X-axis angular velocity data, a Y-axis angular velocity sensor device that outputs digital Y-axis angular velocity data, a Z-axis angular velocity sensor device that outputs digital Z-axis angular velocity data, an acceleration sensor device that outputs digital X-axis, Y-axis, and Z-axis acceleration data, a microcontroller, a first digital interface bus that electrically connects the X-axis angular velocity sensor device, the Y-axis angular velocity sensor device, and the Z-axis angular velocity sensor device to a first digital interface, and a second digital interface bus that electrically connects the acceleration sensor device to a second digital interface.

A micromechanical inertial sensor. The inertial sensor includes a first sensor element for measuring an inertial variable in a first frequency band, and a second sensor element for measuring a periodic acceleration in a second frequency band. The second frequency band is at least partially above the first frequency band.

Sensing devices are described. A sensing device includes an inertial sensor, a read-out circuit configured to determine first data indicative of an acceleration of the structure using an output of the inertial sensor, an energy harvester configured to capture energy, and a power management unit. The power management unit comprises a plurality of energy storage components coupled to the energy harvester and a plurality of switches coupled to respective energy storage components of the plurality of energy storage components. The power management unit monitors energy levels stored in the energy storage components, selectively charges the plurality of energy storage components by selectively activating the plurality of switches, and provides power to one or more of the inertial sensor and the read-out circuit based on the monitored energy levels.

An angular acceleration sensor includes a stationary portion, a weight portion, a beam including a flat plate portion, one end portion of the flat plate portion in a lengthwise direction thereof being connected to the stationary portion and the other end portion thereof being connected to the weight portion, a central projection that projects in a thickness direction of the flat plate portion, and that is disposed at a center of the flat plate portion in a widthwise direction thereof, and end-side projections that are disposed at opposite ends of the flat plate portion in the widthwise direction, respectively, and that project in the thickness direction of the flat plate portion, and detection elements that are disposed on the flat plate portion at positions different from a center of the flat plate portion in the lengthwise direction, and that detect stress generated in the beam.

A hybrid MEMS microfluidic gyroscope is disclosed. The hybrid MEMS microfluidic gyroscope may include a micro-machined base enclosure having a top fluid enclosure, a fluid sensing enclosure and a bottom fluid enclosure. The hybrid MEMS microfluidic gyroscope may include a plurality of cantilevers disposed within the bottom semi-circular portion of the micro-machined base enclosure or a single membrane disposed within the bottom semi-circular portion of the micro-machined base enclosure.

A physical quantity sensor includes a detection circuit that outputs a detection value indicating a physical quantity applied to a detecting element and a correction processor that corrects the detection value to output a corrected value. The correction processor causes the corrected value to be substantially 0 (zero) if all of conditions that an absolute value of a time-differentiated value of the detection value is not larger than a predetermined differential threshold and that an absolute value of the corrected value is not larger than a predetermined output threshold are satisfied. This physical quantity sensor prevents the output signal from changing due a temperature change in spite of a small number of components.

A method for analyzing sensor data from baseball swings (or swings in similar sports) that transforms data into a reference frame defined by the bat orientation and velocity at impact. The trajectory of the sweet spot of the bat is tracked through the swing, and is analyzed to generate metrics describing the swing. A two-lever model of the swing may be used to model the effects of body rotation and wrist rotation. Data may be analyzed to identify relevant events during the swing such as start of downswing, commit (wrist release), on-plane, peak bat speed, and impact. Illustrative swing metrics derived from the sweet spot trajectory, the swing plane reference frame, and the two-lever model include: forward bat speed, on-plane rotation, hinge angle at commit, hinge angle at impact, body rotation ratio, body tilt angle, and swing plane tilt angle.