The present invention comprises apparatuses and methods of detecting impacts to the head. Accelerometers attached to a user's head and neck or body is used to measure the differential acceleration of the head with respect to the neck or body. A differential acceleration exceeding a certain threshold may be indicative of the user suffering a traumatic brain injury.

The present invention comprises apparatuses and methods of detecting impacts to the head. Accelerometers attached to a user's head and neck or body is used to measure the differential acceleration of the head with respect to the neck or body. A differential acceleration exceeding a certain threshold may be indicative of the user suffering a traumatic brain injury.

The invention relates to an accelerometer comprising a plurality of proof-masses (M1-M4) moveable along a measurement axis (AB); a respective spring (K1-K4) rigidly attached to each proof-mass, configured to exert an elastic recall on the proof-mass in the measurement axis; a fixed stop (S1-S4) associated with each proof-mass, arranged to intercept the proof-mass when the acceleration in the measurement axis increases by a step; and an electrical contact associated with each stop, configured to be closed when the associated proof-mass reaches the stop. The proof-masses are suspended in series with respect to one another by springs in the measurement axis, the stops being arranged to successively intercept the respective proof-masses for increasing thresholds of acceleration.

The invention relates to an accelerometer comprising a plurality of proof-masses (M1-M4) moveable along a measurement axis (AB); a respective spring (K1-K4) rigidly attached to each proof-mass, configured to exert an elastic recall on the proof-mass in the measurement axis; a fixed stop (S1-S4) associated with each proof-mass, arranged to intercept the proof-mass when the acceleration in the measurement axis increases by a step; and an electrical contact associated with each stop, configured to be closed when the associated proof-mass reaches the stop. The proof-masses are suspended in series with respect to one another by springs in the measurement axis, the stops being arranged to successively intercept the respective proof-masses for increasing thresholds of acceleration.

An acceleration change sensor includes a flexible member comprising extensions extending from a central portion. Piezoelectric capacitors are provided on respective extensions. A proof mass is coupled to the flexible member and offset from each extension of the plurality of extensions.

An acceleration change sensor includes a flexible member comprising extensions extending from a central portion. Piezoelectric capacitors are provided on respective extensions. A proof mass is coupled to the flexible member and offset from each extension of the plurality of extensions.

A MEMS device includes: a substrate as a base including a support portion and a detection electrode as a fixed electrode; a movable body supported to the support portion with a major surface of the movable body facing the fixed electrode; and an abutment portion facing at least a portion of an outer edge of the movable body and restricting rotational displacement in an in-plane direction of the major surface. The abutment portion includes an abutment surface including an abutment position at which the movable body abuts against the abutment portion due to the rotational displacement of the movable body, and a hollow portion provided opposing the abutment surface.

A MEMS device includes: a substrate as a base including a support portion and a detection electrode as a fixed electrode; a movable body supported to the support portion with a major surface of the movable body facing the fixed electrode; and an abutment portion facing at least a portion of an outer edge of the movable body and restricting rotational displacement in an in-plane direction of the major surface. The abutment portion includes an abutment surface including an abutment position at which the movable body abuts against the abutment portion due to the rotational displacement of the movable body, and a hollow portion provided opposing the abutment surface.

A method includes depositing a silicon layer over a first oxide layer that overlays a first silicon substrate. The method further includes depositing a second oxide layer over the silicon layer to form a composite substrate. The composite substrate is bonded to a second silicon substrate to form a micro-electro-mechanical system (MEMS) substrate. Holes within the second silicon substrate are formed by reaching the second oxide layer of the composite substrate. The method further includes removing a portion of the second oxide layer through the holes to release MEMS features. The MEMS substrate may be bonded to a CMOS substrate.

A method includes depositing a silicon layer over a first oxide layer that overlays a first silicon substrate. The method further includes depositing a second oxide layer over the silicon layer to form a composite substrate. The composite substrate is bonded to a second silicon substrate to form a micro-electro-mechanical system (MEMS) substrate. Holes within the second silicon substrate are formed by reaching the second oxide layer of the composite substrate. The method further includes removing a portion of the second oxide layer through the holes to release MEMS features. The MEMS substrate may be bonded to a CMOS substrate.