For over thirty years, the country has issued hundreds of regulations related to machinery, impact, and handling The standards for state monitoring include:

GB 2298-80 Terminology for Mechanical Vibration and Shock

GB/T 2298-91 Terminology for Mechanical Vibration and Shock

GB/T 2298-2010 Vocabulary for Mechanical Vibration, Shock and Condition Monitoring

QJ 30-81 Sensor Terminology (Ministry of Aerospace Industry Standard)

Extracted information related to "Piezoelectric Accelerators" and supplemented it in this lecture The commonly used noun terms are described below (arranged by English names).

A

A. 1 Absolute calibration

The method of calibrating sensors using fundamental quantities such as amplitude, frequency, etc Methods such as reciprocity, laser interferometry, etc.

A. 2 Acceleration

The rate of change in velocity (vibration and impact).

A. 3 accelerometers

Convert the input acceleration into an output proportional to it (usually Sensors for electrical parameters.

A. 4 Acoustic Sensitivity

The output generated by non acoustic sensors in a specific sound field.

A. 5 amplitude distortion

The ratio of the output of a sensor at a given frequency to its input varies with the input amplitude And the distortion presented by the changes.

B

B. 1. Back to back comparison method

Install the calibrated accelerometer back-to-back with the reference standard accelerometer Install and compare the two

Obtain the sensitivity and frequency of the output under the same vibration Calibration method for response.

B. 2 Base strain sensitivity

Accelerometer generated by specific bending strain on the sensor mounting surface The output.

B. 3 Bell Bell

The base of the logarithm isA unit at 10 o'clock level.

B. 4 bias voltage

Integrated circuit piezoelectric accelerometer in static state (without vibration) The static output presented by the lower output end

State DC voltage. It is determined and provided by the manufacturer, and is subject to acceptance The recording device has an impact and is decoupled using high-value capacitors connected in series.

B. 5 Explosion Wave Blast

The pressure formed by explosions or rapid changes in atmospheric or water pressure Pulse of force and the resulting motion of the medium.

C

C. 1 Charge amplifier

A preamplifier suitable for high resistance and pressure resistant accelerometers, consisting of Composed of operational amplifiers with feedback capacitors, whose output voltage is proportional to the output voltage generated by the sensor The incoming charge is proportional and independent of the cable capacitance.

C. 2. Charge sensitivity

Under the action of unit acceleration or force, high resistance and compression resistance accelerometers The amount of charge generated.

C. 3 Compensation

Adopting measures such as special structures, additional devices, circuits, or special materials Apply cancellation or reduction of sensor errors.

C. 4 Compliance voltage

Integrated circuit piezoelectric accelerometer obtains direct current from a constant current source Voltage. Due to the voltage drop of a constant current source, it is usually lower than the power supply voltage.

C. 5 crest factor

The ratio of peak value to root mean square value, and the crest factor of a sine wave are.

C. 6 Critical damping

Return a single degree of freedom system that deviates from its equilibrium position to its initial state without oscillation The minimum viscous damping at the starting position.

C. 7 Cross talk Interference

Observing within a signal channel due to interference from other channel signals The signal of arrival.

C. 8 cycles (noun)

The state or number of a periodic phenomenon or function before its repeated occurrence The entire range that the value has experienced.

D

D. 1. Damping natural frequency

The free vibration frequency of a damped linear vibration system.

D. 2 Damping

The dissipation of energy over time or distance.

D. 3 damping ratio

The ratio of actual damping coefficient to critical damping coefficient.

D. 4 decibels decibel

dB

One tenth of Bell's.

D. 5 degrees of freedom

The independence required to determine the position of a mechanical system at any given time The generalized coordinate number.

D. 6 discharge time constant

The discharge time constant of the sensor depends on the circuit designThe RC time constant defines the time required for the initial signal to drop to 37%.

D. 7 Displacement

relative displacementrelative displacement

(Vibration and impact) characterize the position of a point on an object relative to a reference frame Set the time variable for changes.

D. 8 duration of shock pulse

The impulse pulse rises (or falls) from the reference value to the maximum value The time required to return to the baseline value (small value). For the measured pulse, the reference value is taken value1/10, set to 0 for ideal pulses.

D. 9 Dynamic Range

The signal and minimum signal that sensors can measure without distortion The ratio is generally usedDecibel "represents.

E

E. 1 Effective bandwidth

When a certain bandpass filter and another ideal bandpass filter with a flat response in the passband input the same white noise, if the energy transmitted by both filters is the same, the bandwidth of the latter is called the effective bandwidth of the bandpass filter.

E. 2 effective responses

The response of a sensor in the direction of its sensitive axis caused by input mechanical vibration or impact. This response is expected to be obtained by using sensors correctly for measurement and obtaining reliable data.

E. 3 Electrical isolation

The output and ground terminals of the sensor are electrically insulated from its mounting surface.

E. 4 Electromagnetic Sensitivity

The output value generated by an accelerometer in a specified electromagnetic field.

E. 5 incentive excitation

An external force or other input that acts on the system and causes it to produce a certain response.

F

F. 1 Ferroelectric material

A branch of piezoelectric materials with high dielectric constant, such as lead zirconate titanate（PZT）。

F. 2 Force Transducers

A sensor that converts input force into an output proportional to it.

F. 3 Forced vibration

A system vibration excited by an external force related to time, also known asForced vibration.

F. 4. Free vibration

The vibration that occurs in the system after the removal of incentives or constraints.

F. 5 frequencies

The reciprocal of the cycle.

F. 6 Frequency distortion

Within a given frequency range, for a given excitation, the amplitude sensitivity of the sensor is not

Distortion caused by constants.

F. 7 frequency response

The characteristic of the amplitude and phase of the sensor output signal changing with the frequency of the input quantity. Also known as amplitude frequency response and phase frequency response, respectively.

G

G. 1 Ground loop

The closed loop formed by the potential difference between the sensor and the measuring instrument grounding point can increase interference.

H

H. Half sine shock pulse

The time history curve is an ideal impulse pulse of a half sine wave.

H. 2-harmonic harmonic

A sine wave with a frequency that is an integer multiple of the fundamental frequency.

H. 3 Hermetically sealed gas seals

A commonly used sealing method and structural form in sensor design, usually using a welded structure, with glass and metal sealed connections at the interface.

I

I. 1 Ideal Shock Pulse

A shock pulse that can be described using a simple time function.

I. 2 collision impact

A single collision between one quality and another quality.

I. 3 Impedance

In a steady linear system, the ratio of the harmonic excitation of the system represented by a complex number to its response.

I. Integrated Electronics Piezoelectric (IEPE)

A piezoelectric accelerometer equipped with a preamplifier that converts high impedance input signals into low impedance voltage output signals. Different manufacturers have named different business names.

I. 5. Integrated mechanical filter accelerometer

filter accelerometer

An accelerometer with a mechanical filter installed in the housing, the conversion characteristics of the entire system are determined, and it is much better than an external mechanical filter.

J

J. 1. Increase acceleration jerk

The vector that characterizes the time derivative of acceleration.

L

L. 1. Linearity (non-linearity)

When the ratio of the sensor output electrical signal to the input mechanical quantity is always constant at any given vibration level, the output of the sensor is called linear. The degree of deviation from a constant is called nonlinearity and is generally expressed as a percentage of the full scale.

L. 2 linear damping

Damping generated by forces that are proportional to speed but opposite in direction.

M

M. 1. Mass loading error

The structural response error caused by adding additional mass to the accelerometer. Generally speaking, the mass of an accelerometer should be less than one tenth of the mass of the object being measured.

M. 2 mass spring type transducer

The sensor is fixed to a moving object, and the motion of the measured moving object is inferred from the motion of the mass block relative to the base in the sensor.

M. 3 Mean time beta failure

（MTBF is a conventional method for calculating/predicting the working life of instruments.

M. 4. Micromachining for Micro Machining

The manufacturing process of using anisotropic etching forming technology to process single silicon wafers into integral sensitive structures.

M. 5. Install resonance frequency mount

The natural frequency of the system when the sensor is installed on a rigid mass.

M. 6-degree-of-freedom system

A system that requires two or more generalized coordinates at any given time to determine its state.

N

N. 1. Natural frequency (of a mechanical system)

The free vibration frequency of an undamped linear vibration system.

N. 2 Noise

Unwanted signals. It usually has random properties and does not contain well-defined frequency components in its spectrum.

N. 3 low-noise cables with noise treated cables

A specialized cable designed for high resistance and compression resistance electric accelerometer systems, which has been specially processed to generate frictional electrical noise.

O

O. 1. Over damping

Damping ratio greater thanDamping of 1.

Underdampedunder damping

Damping ratio less thanDamping of 1.

O. 2 Overload capability

The ability of a sensor to withstand excessive mechanical input beyond its rated full range without causing any damage.

O. 3 overshoot, negative overshoot, and overshoot

Increasing the input of the system to change its output from a steady-state value to a larger steady-state value, the transient response value exceeding the new steady-state value is called overshoot, and the minimum transient response value below the new transient value is called negative overshoot.

P

P. Peak to peak value (of a vibration)

The difference between positive and negative vibration values within a given time interval.

P. 2 peak values

Peak sizepeak magnitude

Positive peak valuepositive peak value

Negative peak valuenegative peak value

Vibration values within a given time interval.

P. 3 cycle period

The minimum time increment in which a periodic function repeats itself.

P. 4 cycles of periodic vibration

Vibration parameter refers to the vibration that can repeatedly occur as an independent variable over time after a certain increment.

P. 5 phase angles

The complex response complex angle that characterizes the time displacement characteristics at a given frequency.

P. 6 Phase difference

Phase angle differencephase angle difference

The difference in phase angle between two harmonic vibrations with the same frequency. If it is a sinusoidal vibration, it is the difference in phase angles measured from the same reference.

P. 7 phase distortion

The distortion exhibited when the phase shift of a sensor is not a linear function of frequency.

P. 8 piezoelectric accelerometer (PE)

A sensor that uses piezoelectric materials as sensitive components and functions as a spring in a mass spring system. The amount of charge generated is proportional to the input acceleration.

P. 9 piezoelectric coefficients

Characterize the amount of charge generated under the action of a unit force, measured in picocoulombs/Newton.

P. 10 polarization voltage

To achieve piezoelectric effect in piezoelectric ceramics, a high direct current voltage is applied.

P. 11 pulse drop off time

The time interval required for the pulse value to decrease from the larger fraction of a set value to the smaller fraction of the set value.

P. 12 pulse rise time

The time interval required for a pulse to rise from a smaller fraction of a set value to a larger fraction of the set value.

P. 13 thermoelectric effect

The phenomenon of charge output generated by piezoelectric accelerometers when subjected to temperature transients.

P. 14 Explosion Impact Pyroshock

The response of structures to high-frequency, high amplitude shock waves generated by explosions.

R

R. 1. Random vibration; stochastic vibration

Vibration with unpredictable instantaneous values.

R. 2 Reference Sensitivity

The sensitivity value of the sensor at a given reference frequency and reference amplitude.

R. 3 Reliability

The probability of the piezoelectric accelerometer working normally under specified time, environmental conditions, maintenance conditions, and usage conditions.

R. 4 repeatability

The consistency of the characteristic curve of a piezoelectric accelerometer when the input acceleration changes continuously in the same direction over the entire measurement range multiple times under the same working conditions.

R. 5 Resolution

The minimum change in input quantity when the output quantity of the piezoelectric accelerometer measurement system can be distinguished.

R. 6 Resonance Frequency

When the system undergoes forced vibration, any small change in excitation frequency will cause a decrease in its response to the vibration state, which is the value of the response, and the frequency at this time is the resonance frequency. When a piezoelectric accelerometer is installed on a rigid structure, the stiffness of the system will increase the resonance frequency. Generally speaking, the installed resonance frequency is higher than the uninstalled resonance frequency (natural frequency).

R. 7 Response

The output of a piezoelectric accelerometer after being subjected to input acceleration.

S

S. 1 Inertial sensor seismic transducer

A sensor that generates an output signal proportional to the motion of the base based on the relative motion between the mass block and the base in a single degree of freedom system.

S. 2 Self generating electricity

In piezoelectric accelerometers, piezoelectric elements are used as sensitive components to generate output electrical signals without the need for an external power source, which is calledSelf generated electricity.

S. 3 sensitive elements

The component used in sensors that can sense the measured physical quantity. In piezoelectric accelerometers, piezoelectric elements are sensitive components.

S. 4 sensitive axes

The nominal axis of a linear sensor with sensitivity.

S. 5 Sensitivity

The ratio of the specified output to the specified input of the sensor.

S. 6 Shear type piezoelectric accelerometer

A piezoelectric accelerometer that generates output electrical signals by utilizing the shear deformation of piezoelectric elements.

S. 7 impact shock

Sudden changes in force, position, velocity, or acceleration that can trigger transient disturbances in the system.

S. 8 Shock Motion

Transient motion generated by impact excitation.

S. 9 shock pulses

A form of impact excitation characterized by sudden increases or decreases in time-varying parameters such as displacement, force, or velocity.

S. 10 Shock Response Spectrum (SRS)

A description of the response (displacement, velocity, or acceleration) of a series of single degree of freedom systems subjected to mechanical impact as a function of the natural frequencies of each system. If not specified, the system is considered to be undamped.

S. 11 Simple harmonic vibration

Sinusoidal vibrationsinusoidal vibration

The vibration parameter is a periodic vibration that can be described by the sine function of the time independent variable.

S. 12 Single degree of freedom system

A system that can determine its state at any time with just one coordinate.

S. 13 Chaotic Response

The response of sensors caused by other physical factors that coexist when measuring mechanical vibrations or impacts. This response interferes with accurate measurements and is not expected.

S. 14 Stability and Stability

The degree to which a piezoelectric accelerometer maintains its original performance under the same conditions for a certain period of time.

S. 15 Durability and Survivability

The ability of piezoelectric accelerometers to withstand external environmental conditions (such as impact, high temperature, etc.) without any changes in performance.

T

T. 1. Temperature response

The variation of the output signal generated by a piezoelectric accelerometer with temperature within a specific temperature range, also known as the temperature coefficient. Generally given as the percentage change in sensitivity with temperature.

T. 2. Thermal transient sensitivity

The output signal generated by a piezoelectric accelerometer when subjected to instantaneous temperature changes.

T. 3 Temperature Zero Drift Thermal Zero Drift

The zero point change caused by the deviation of the operating temperature of a piezoelectric accelerometer from the calibration temperature.

T. 4 Sensor Distortion Transformer Distortion

The unwanted changes in the output waveform of sensors can be divided into amplitude distortion, frequency distortion, and phase distortion.

T. 5-sensor phase shift transducer phase shift

The phase difference between the output and input of the sensor during sinusoidal excitation.

T. 6 Lateral sensitivity

Lateral sensitivity ratiotransverse sensitivity ratio

The sensitivity of a piezoelectric accelerometer when excited in a direction perpendicular to the sensitive axis is referred to as the lateral sensitivity ratio, which is generally expressed as a percentage.

V

V. 1 Speed velocity

relative velocityrelative velocity

The rate of change of displacement (vibration and impact).

V. 2 Vibration

Mechanical oscillation around a certain equilibrium point. This oscillation can be periodic or random.

V. 3 Voltage sensitivity

The rated voltage output generated by a piezoelectric accelerometer when subjected to a specific acceleration. For high impedance piezoelectric accelerometers, it refers to the sensitivity of their open circuit voltage output, while for integrated circuit piezoelectric accelerometers, it refers to the sensitivity of their output voltage.

W

W.1 波形失真 wave distortion

The unwanted changes that occur in vibration and shock waveforms.

Z

Z. 1 Zero measured output

The output value when the measured physical quantity is zero after the sensor is powered on.

Z. 2 Zero Shift

Under strong impact, the displacement of the zero position line output by piezoelectric accelerometers may be due to mechanical, electrical, or temperature reasons. All accelerometers will experience a certain degree of zero position drift under strong impact.