A device for detecting a sudden pressure variation in a fluid, including a housing open at one of its ends, a wall closing the housing to create a chamber, the wall being configured such that, when the external pressure outside the chamber is substantially stable or varies slowly, the internal pressure of the chamber is close to the external pressure, and the wall having mechanical characteristics such that it breaks when subjected to a predetermined difference between the external pressure and the internal pressure.

A device for detecting a sudden pressure variation in a fluid, including a housing open at one of its ends, a wall closing the housing to create a chamber, the wall being configured such that, when the external pressure outside the chamber is substantially stable or varies slowly, the internal pressure of the chamber is close to the external pressure, and the wall having mechanical characteristics such that it breaks when subjected to a predetermined difference between the external pressure and the internal pressure.

Disclosed is a method and device suitable for detection of and warning against tsunamis. The device is located in the water at sea. The device includes a vessel, a sensor for measuring a physical quantity of the surrounding water, a control unit inside the vessel and operatively connected to the sensor, and a communication element including a transmitter for communicating with an external receiver that the predetermined condition relating to the physical quantity is fulfilled. The device further includes a ballast tank inside the vessel. The interior of the ballast tank is connected to the outside of the vessel. A pump pumps water from the ballast tank to outside the vessel. The overall density of the device exceeds the density of the surrounding water when the ballast tank is filled, and is less than the density of the surrounding water when the ballast tank is empty of water.

Disclosed is a method and device suitable for detection of and warning against tsunamis. The device is located in the water at sea. The device includes a vessel, a sensor for measuring a physical quantity of the surrounding water, a control unit inside the vessel and operatively connected to the sensor, and a communication element including a transmitter for communicating with an external receiver that the predetermined condition relating to the physical quantity is fulfilled. The device further includes a ballast tank inside the vessel. The interior of the ballast tank is connected to the outside of the vessel. A pump pumps water from the ballast tank to outside the vessel. The overall density of the device exceeds the density of the surrounding water when the ballast tank is filled, and is less than the density of the surrounding water when the ballast tank is empty of water.

An apparatus for testing a pressure change rate of a component in an electro-pneumatic braking system of a commercial vehicle includes a pressure change rate test bench, a pneumatic loop configured to implement on-off control of air and detection on a pressure change rate of a tested component in an electro-pneumatic braking system of a commercial vehicle, a signal processing unit configured to acquire a pressure signal and a differential pressure signal and perform analog-digital conversion on the signals to provide signals recognizable by an upper controller and a lower execution component, and a control unit configured to communicate with the pneumatic loop and drive the components in the pneumatic loop to act by setting a control parameter to obtain test data of the tested component in the electro-pneumatic braking system of the commercial vehicle in the pneumatic loop.

An apparatus for testing a pressure change rate of a component in an electro-pneumatic braking system of a commercial vehicle includes a pressure change rate test bench, a pneumatic loop configured to implement on-off control of air and detection on a pressure change rate of a tested component in an electro-pneumatic braking system of a commercial vehicle, a signal processing unit configured to acquire a pressure signal and a differential pressure signal and perform analog-digital conversion on the signals to provide signals recognizable by an upper controller and a lower execution component, and a control unit configured to communicate with the pneumatic loop and drive the components in the pneumatic loop to act by setting a control parameter to obtain test data of the tested component in the electro-pneumatic braking system of the commercial vehicle in the pneumatic loop.

Disclosed is a method and an apparatus for measuring the pressure of fresh concrete and similar liquid materials during placement, in which a movable component is displaced under the pressure of concrete or other liquids and is used as an indicator of the pressure exerted by the concrete or liquid material on the device. Mechanical resistance of the movable component is achieved using a calibrated spring or similar mechanical resistance element. The movable part consists of a pressure plate attached to a scaled cylindrical core, calibrated to provide measurements of the external concrete or liquid pressure. The movable component and mechanical resistance element are installed in a casing with flanges to attach the apparatus to the formwork or vessel.

Systems and methods for pressure measurement are provided. A ludion with a trapped gas bubble floats between two liquids. Pressure acting upon the liquids causes the bubble to expand or contract, resulting in movement of the ludion which can be measured and correlated with pressure change. Pressure measuring device can measure pressures from 0.05 inHg to 110 inHg with a four-to-one Test Accuracy Ratio (TAR) without using mercury.

A seat assembly with an adjustable head restraint assembly capable of being adjusted based on an approximate stature or spatial location of an occupant in the seat assembly. A seat assembly may include a sensor in the seat to detect if an occupant is present. The sensor may include a plurality of bladders and pressure sensors, a radar system, or a neuro-monitoring sensor. The sensor may send a signal to a controller indicating the presence of an occupant. The controller may approximate the size and/or spatial location of the occupant and send an adjustment signal to the head restraint adjustment mechanism to adjust the head restraint assembly to an in-use position. The controller may determine that an occupant is not present and send an adjustment signal to the head restraint adjustment mechanism to adjust the head restraint assembly to a non-use position.

A seat assembly with an adjustable head restraint assembly capable of being adjusted based on an approximate stature or spatial location of an occupant in the seat assembly. A seat assembly may include a sensor in the seat to detect if an occupant is present. The sensor may include a plurality of bladders and pressure sensors, a radar system, or a neuro-monitoring sensor. The sensor may send a signal to a controller indicating the presence of an occupant. The controller may approximate the size and/or spatial location of the occupant and send an adjustment signal to the head restraint adjustment mechanism to adjust the head restraint assembly to an in-use position. The controller may determine that an occupant is not present and send an adjustment signal to the head restraint adjustment mechanism to adjust the head restraint assembly to a non-use position.