This disclosure provides systems, methods, and apparatus related to an ultrasonic microphone and an ultrasonic acoustic radio. In one aspect a system includes a transmitter and a receiver. The receiver comprises a membrane. The membrane comprises a single layer or multiple layers of a two-dimensional material. The receiver is operable to receive sound waves in a frequency range, with the frequency range being the ultrasonic frequency range.

It is important to trap and identify mosquitos to ensure the safety of the population where mosquitos gather. The classification of a type of mosquito is typically accomplished by a unique wingbeat signature that is characteristic of different types of mosquitos. One of the goals of the trap is to quickly identify the mosquito and then quickly release the mosquito. This application will allow the user to obtain an approximate population so that the appropriate type and amount of insecticide can be applied to control the population to insure the health of the human and animal population while at the same time minimizing danger to the environment or surrounding ecosystem.

One of the main objects of the present invention is to provide a vibration sensor with improved sensitivity. To achieve the above-mentioned objects, the present invention provides a vibration sensor including a circuit board assembly including an installation slot; a housing fixed to the circuit board assembly for forming an accommodation space cooperatively with the circuit board assembly; and a diaphragm assembly accommodated in the accommodation space and secured to the circuit board assembly. The diaphragm assembly includes a gasket fixed to the circuit board assembly, and a first diaphragm fixed to a side of the gasket away from the circuit board assembly.

One of the main objects of the present invention is to provide a vibration sensor with improved sensitivity. To achieve the above-mentioned objects, the present invention provides a vibration sensor including a circuit board assembly including an installation slot; a housing fixed to the circuit board assembly for forming an accommodation space cooperatively with the circuit board assembly; and a diaphragm assembly accommodated in the accommodation space and secured to the circuit board assembly. The diaphragm assembly includes a gasket fixed to the circuit board assembly, and a first diaphragm fixed to a side of the gasket away from the circuit board assembly.

One of the main objects of the present invention is to provide a vibration sensor with improved sensitivity. To achieve the above-mentioned object, the present invention provides a vibration sensor including a circuit board assembly; a housing fixed to the circuit board assembly for forming an accommodation space cooperatively with the circuit board assembly; and a diaphragm assembly accommodated in the accommodation space and secured to the circuit board assembly. The diaphragm assembly includes a gasket fixed to the circuit board assembly, and a first diaphragm fixed to a side of the gasket away from the circuit board assembly. The sensor further includes a vibration cavity enclosed by the gasket, the first diaphragm, and the circuit board assembly, and a MEMS microphone accommodated in the vibration cavity and electrically connected to the circuit board assembly.

One of the main objects of the present invention is to provide a vibration sensor with improved sensitivity. To achieve the above-mentioned object, the present invention provides a vibration sensor including a circuit board assembly; a housing fixed to the circuit board assembly for forming an accommodation space cooperatively with the circuit board assembly; and a diaphragm assembly accommodated in the accommodation space and secured to the circuit board assembly. The diaphragm assembly includes a gasket fixed to the circuit board assembly, and a first diaphragm fixed to a side of the gasket away from the circuit board assembly. The sensor further includes a vibration cavity enclosed by the gasket, the first diaphragm, and the circuit board assembly, and a MEMS microphone accommodated in the vibration cavity and electrically connected to the circuit board assembly.

An object of the present invention is to provide a method of a practical level for performing sensor fusion of multiple vibration sensors such as a seismometer, and in an example, to extend a dynamic range of a high-sensitivity geophone by sensor fusion of the high-sensitivity geophone and a low-sensitivity acceleration geophone. A state related to the high-sensitivity geophone is estimated by capturing, in a Kalman filter, an acceleration record from the low-sensitivity acceleration geophone and a velocity record, or a displacement record, and an acceleration record of the high-sensitivity geophone, and estimating and calculating them as the linear Kalman filter problem with a control input. The high-sensitivity geophone is an actual device, but the state can be estimated using a sensor value of the low-sensitivity acceleration geophone even when the record is saturated. This extends the dynamic range of the high-sensitivity geophone.

Methods for noninvasive determination of acoustical properties of flowing in pipes having a large ratio (>10) of pipe diameter to wall thickness, and in highly attenuating fluids are described. When vibrations are excited on the outer surface of the wall of a pipe, the resulting vibrations propagate directly through the wall in a normal direction and through the pipe wall as guided waves, appearing on the opposite side of the pipe. This dual path propagation through pipes, where guided waves take the circumferential path in the wall of the pipe and may interfere with the time of-flight measurement obtained from the direct path through the fluid, is at least in part resolved by subtracting the signal from the guided wave from the combined signal, thereby permitting improved observation of the direct path propagation through the fluid.

Methods for noninvasive determination of acoustical properties of flowing in pipes having a large ratio (>10) of pipe diameter to wall thickness, and in highly attenuating fluids are described. When vibrations are excited on the outer surface of the wall of a pipe, the resulting vibrations propagate directly through the wall in a normal direction and through the pipe wall as guided waves, appearing on the opposite side of the pipe. This dual path propagation through pipes, where guided waves take the circumferential path in the wall of the pipe and may interfere with the time of-flight measurement obtained from the direct path through the fluid, is at least in part resolved by subtracting the signal from the guided wave from the combined signal, thereby permitting improved observation of the direct path propagation through the fluid.

The present disclosure relates to a valve assembly including a valve moveable between an open position where hydraulic fluid flow is permitted between first and second ports of the valve and a closed position where hydraulic fluid flow is blocked between the first and second ports. A characteristic vibration is generated by turbulent hydraulic fluid flow within the valve when hydraulic fluid flow is first initiated between the first and second ports as the valve moves from the closed position toward the open position. The valve assembly also includes a controller for providing electrical current to control movement of the valve via a solenoid. The controller includes an accelerometer for sensing the characteristic vibration. The controller identifies an electrical current value of the electrical current at a time when the characteristic vibration is detected.