An electronic device includes a substrate, a functional element disposed on a principal plane of the substrate, a lid body, the functional element being housed in a space covered by the lid body and the substrate, the lid body including a recess at a side opposed to the functional element, an outer surface at the opposite side of the recess, a first hole section including an inclined surface and a bottom surface on the outer surface, and a second hole section piercing through the lid body between the recess and the bottom surface and having an inner wall surface, a joining section of the inclined surface and the bottom surface in the first hole section being a curved surface, the lid body containing silicon, and a sealing member that seals the first hole section communicating with the space.

A wearable user device includes a first hearing aid configured to be disposed within a first ear of a user comprising a first MEMS accelerometer, a first magnetometer, and a first power source, wherein the first MEMS accelerometer is configured to determine a first plurality of movement data in response to a first head motion of the user, wherein the first magnetometer configured to determine a second plurality of movement data in response to the first head motion of the user; and wherein the first power source is configured to provide operating power to the first hearing aid, the first MEMS accelerometer, and to the first magnetometer, and a processor coupled to the first hearing aid, wherein the processor is configured to determine a first plurality of rotation data associated with the user in response to the first plurality of movement data and the second plurality of movement data.

A sensor device includes an angular velocity sensor element, an acceleration sensor element, an intermediate member, and an elastic body. Both the angular velocity sensor element and the acceleration sensor element are mounted on the intermediate member. The elastic body is connected to the intermediate member and a fixing part located apart from the intermediate member. The intermediate member is configured to vibrate by receiving a vibration applied to the fixing part.

A rotational acceleration sensor having a substrate, a mass movable with respect to the substrate, a suspension means suspending the mass movably relative to the substrate, a detection means for detecting a state of the mass deflected with respect to an idle position, and a detection means encompassing a first detection unit for detecting a deflected state of the mass i.e., a pivoting of the mass around a first axis substantially perpendicular to a principal extension plane of the substrate as a result of a rotational acceleration of the rotational acceleration sensor around the first axis. The detection means also encompassing a second detection unit for detecting a deflected state of the mass, i.e., a pivoting of the mass around a second axis substantially parallel to the principal extension plane of the substrate as a result of a rotational acceleration of the rotational acceleration sensor around the second axis.

Angular accelerometers are described, as are systems employing such accelerometers. The angular accelerometers may include a proof mass and rotational acceleration detection beams directed toward the center of the proof mass. The angular accelerometers may include sensing capabilities for angular acceleration about three orthogonal axes. The sensing regions for angular acceleration about one of the three axes may be positioned radially closer to the center of the proof mass than the sensing regions for angular acceleration about the other two axes. The proof mass may be connected to the substrate though one or more anchors.

Techniques for resolving hemisphere ambiguity are disclosed. One or more magnetic fields are emitted at a handheld controller. The one or more magnetic fields are detected by one or more sensors positioned relative to a headset. Movement data corresponding to the handheld controller or the headset is detected. During a first time interval, a first position and a first orientation of the handheld controller within a first hemisphere are determined based on the detected one or more magnetic fields, and a first discrepancy is calculated based on the first position, the first orientation, and the movement data. During a second time interval, a second position and a second orientation of the handheld controller within a second hemisphere are determined based on the detected one or more magnetic fields, and a second discrepancy is calculated based on the second position, the second orientation, and the movement data.

A system that measures a swing of a bat with one or more sensors and analyzes sensor data to create swing quality metrics. Metrics may include for example rotational acceleration, on-plane efficiency, and body-bat connection. Rotational acceleration measures the centripetal acceleration of the bat along the bat's longitudinal axis at a point early in the rotational part of the swing; it is an indicator of the swing's power. On-plane efficiency measures how much of the bat's angular velocity occurs around the swing plane, the plane spanned by the bat and the bat's sweet spot velocity at impact. Body-bat connection measures the angle between the bat and the body tilt axis, which is estimated from the trajectory of the hand position on the bat through the swing; an ideal bat-body connection is near 90 degrees. These three swing quality metrics provide a simple and useful characterization of the swing mechanics.

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.

A method for determining a vehicle wheel's radial acceleration for a tyre pressure monitoring system, having a central electronic unit. The wheels each including a wheel unit attached to a rim or to a valve or the tyre tread's inner face, and including at least one radial acceleration sensor at a distance from the wheel's rotational axis, to measure the wheel's radial acceleration when it is not saturated, and a microprocessor, including: when the radial acceleration sensor is not saturated, measuring the radial acceleration of the wheel using the radial acceleration sensor; determining the wheel's rotation period; deducing, from the radial acceleration and the period, the distance of the wheel unit; storing the distance in the wheel unit's memory; and when the radial acceleration sensor is saturated, determining the wheel's rotation period, and calculating the radial acceleration from the rotation period and the stored distance.

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.