How Does a Piezoelectric Pressure Sensor Work?

Piezoelectric pressure sensors work based on the piezoelectric effect. They use electrical components and other mechanical devices to convert the pressure to be measured into electrical quantity, and then perform related measurements. Piezoelectric sensors are mainly used in dynamic measurements, and their sensitive components are made of piezoelectric materials.

The working principle of piezoelectric pressure sensors is based on the piezoelectric effect. When piezoelectric materials are subjected to external forces, electric charges are formed on their surfaces, and the amount of charge is proportional to the external force. These charges are converted into electrical outputs proportional to the external force after being amplified by charge amplifiers, measurement circuits, and impedance conversion.

The main piezoelectric materials used in piezoelectric pressure sensors include diammonium phosphate, potassium sodium tartrate, quartz, etc. With the development of technology, the piezoelectric effect has also been applied to polycrystalline materials, such as piezoelectric ceramics (such as magnesium niobate piezoelectric ceramics, niobate piezoelectric ceramics and barium titanate piezoelectric ceramics).

Advantages: light weight, reliable operation, simple structure, high signal-to-noise ratio, high sensitivity and signal bandwidth.
Disadvantages: Some piezoelectric materials are afraid of moisture and need to take moisture-proof measures; the output current response is poor, and charge amplifiers or high input impedance circuits are often used to compensate.

Piezoelectric pressure sensors are suitable for dynamic pressure measurement scenarios, such as sound and vibration measurements. Due to the characteristics of the piezoelectric effect, it is not suitable for static force measurement.

Standard equipment is required to calibrate piezoelectric pressure sensors, such as high-precision standard pressure sources, digital oscilloscopes and multimeters. The calibration steps include connecting the equipment, setting calibration parameters, performing zero calibration and full-scale calibration, and linear calibration. After calibration, multiple tests should be performed to ensure accuracy, and the calibration results should be recorded.

Problems that may occur during the use of piezoelectric pressure sensors include unstable pressure indication, large pressure indication deviation, no output or abnormal output signal. These problems may be caused by loose wiring, internal circuit failure, electromagnetic interference, zero offset, wrong range setting or sensor damage.

For problems that occur during the use of piezoelectric pressure sensors, the following measures can be taken to solve them: check the wiring to ensure firmness, repair or replace sensors suspected of internal circuit failure, take shielding and grounding measures to reduce electromagnetic interference, perform zero calibration and reset the range of the sensor, check and replace aging sensors, etc.

The stability of a piezoelectric pressure sensor refers to the ability of the sensor to maintain its function unchanged after a period of use.

The main factors affecting the stability of a piezoelectric pressure sensor include the sensor’s range, operating environment, etc. Improper range selection or environmental interference may affect the stability of the sensor.

When selecting a piezoelectric pressure sensor, the maximum pressure measurement value of the system equipment should be determined first. Generally, a pressure sensor that is 1.5 times larger than the maximum value of the medium should be selected to take into account irregular fluctuations above the peak value.

A piezoelectric pressure sensor with poor stability may lead to inaccurate measurement data, affect the normal operation of the equipment and the credibility of the monitoring system, and in severe cases may even lead to equipment failure or safety accidents.

Methods to improve the stability of a piezoelectric pressure sensor include selecting a suitable range, optimizing the operating environment, taking shielding and grounding measures to reduce electromagnetic interference, and regular calibration and calibration.

To ensure the stable performance of the sensor, it is recommended to calibrate the piezoelectric pressure sensor once a year.

Possible causes of failure include unstable pressure source itself, loose sensor wiring or poor contact, internal circuit failure of the sensor, and external electromagnetic interference.

Methods to solve the abnormal output signal of piezoelectric pressure sensor include checking whether the output signal exceeds the range, adjusting the range setting of the sensor, recalibrating the sensor, and taking shielding and grounding measures to reduce interference.

The accuracy of piezoelectric pressure sensor refers to the closeness of the measured value reported by the sensor to the actual pressure, usually expressed as a percentage of the full scale (FS) of the sensor.

Factors affecting the accuracy of piezoelectric pressure sensor include nonlinearity, hysteresis, temperature effect, zero output change, and the manufacturing and calibration accuracy of the sensor itself.

Nonlinearity is the deviation of the sensor output from a specified best fit straight line over the full scale range. Nonlinearity errors cause a difference between the sensor’s measured value and the actual value, affecting accuracy.

Hysteresis refers to the consistency of the sensor’s output signal when it is loaded in the forward and reverse directions. Hysteresis causes the sensor to produce different output values ​​at the same pressure, affecting accuracy.

Methods to improve the accuracy of piezoelectric pressure sensors include selecting high-precision sensors, performing temperature compensation, regular calibration and inspection, optimizing the structural design of sensors, and using digital signal processing technology.

Temperature affects the performance of piezoelectric materials, resulting in changes in the output signal of the sensor. Therefore, when using piezoelectric pressure sensors in high or low temperature environments, temperature compensation issues need to be considered to improve accuracy.

The calibration cycle of piezoelectric pressure sensors depends on the use environment and frequency. It is generally recommended to calibrate the sensor regularly (such as every year or every six months) according to the use environment and changes in the performance of the sensor.

The accuracy of piezoelectric pressure sensors can be evaluated by comparing the difference between the measured values ​​and the actual values ​​of the sensor at different pressures. In addition, the accuracy specifications and calibration certificates provided by the sensor manufacturer can be referred to to evaluate its accuracy.

If the accuracy of the piezoelectric pressure sensor does not meet the standard, it may cause inaccurate measurement data, which in turn affects the normal operation of the equipment and the credibility of the monitoring system. In severe cases, it may even cause equipment failure or safety accidents.

Piezoelectric pressure sensors are widely used in the military industry to measure the changes in chamber pressure when gun bullets are fired in the chamber, the shock wave pressure at the muzzle, etc., as well as for pressure monitoring and control systems of aircraft such as missiles and rockets.

Piezoelectric pressure sensors have the advantages of high precision, high sensitivity, fast response and good stability, which are very suitable for occasions in the military industry where pressure measurement accuracy and reliability are extremely high.

In missile guidance systems, piezoelectric pressure sensors are used to measure the aerodynamic pressure of missiles during flight and provide key data for the missile’s control system to ensure that the missile can accurately hit the target.

In armored vehicles such as tanks, piezoelectric pressure sensors can be used to monitor the air pressure of tires or tracks, as well as the combustion pressure inside the engine, providing important information for vehicle maintenance and safe operation.

When selecting piezoelectric pressure sensors in the military industry, factors such as the sensor’s range, accuracy, sensitivity, stability, response time, and working environment need to be considered to ensure that the sensor can meet the actual application requirements.

In the military industry, the calibration and maintenance of piezoelectric pressure sensors are crucial. Regular calibration is required to ensure the accuracy of the sensor, and attention should be paid to the storage environment and protective measures of the sensor to avoid damage or contamination of the sensor.

Although piezoelectric pressure sensors are mainly used for pressure measurement, in military communications, they may be used as part of a pressure-triggered switch or pressure sensor device to detect signal transmission or trigger communication actions under specific pressure conditions. However, this is not its main application, but more of an auxiliary role in a specific system or device.

With the continuous development of military technology, the requirements for piezoelectric pressure sensors will become higher and higher. In the future, piezoelectric pressure sensors will develop in the direction of higher precision, higher sensitivity, smaller size and better stability to meet the higher demand for pressure measurement in the military industry.

Piezoelectric pressure sensors are widely used in industrial automation to monitor and control pressure changes in the production process, such as hydraulic systems, gas transportation and storage, mechanical engineering, aerospace, environmental monitoring and other fields.

In hydraulic system, piezoelectric pressure sensor can monitor the pressure of hydraulic oil in real time to ensure that the system operates within the normal range, and adjust the working state of the pump in time through feedback control to improve production efficiency and safety.

In gas transportation and storage, piezoelectric pressure sensor can prevent equipment damage or safety accidents caused by excessive pressure and ensure the safe operation of the system.

In mechanical engineering, piezoelectric pressure sensors are widely used in the monitoring and maintenance of mechanical equipment, such as monitoring the fuel pressure of the engine, monitoring the air pressure in the fermentation tank, etc., to help engineers perform fault analysis and predictive maintenance.

In the aerospace field, the application of piezoelectric pressure sensors is particularly important. It can be used to monitor the pressure difference between the inside and outside of the cabin to ensure the safety and comfort of passengers, while monitoring the pressure of fuel and oxidizer in real time to ensure the normal operation of the propulsion system.

In industrial automation, piezoelectric pressure sensors may face challenges in harsh environmental conditions such as high temperature, high pressure, and strong electromagnetic interference, and need to have high stability and reliability.

Improving the accuracy and stability of piezoelectric pressure sensors in industrial automation can be achieved by optimizing sensor design, selecting appropriate ranges and accuracy levels, taking shielding and grounding measures to reduce electromagnetic interference, and regular calibration and maintenance.

With the continuous development of industrial automation technology, piezoelectric pressure sensors are developing towards higher accuracy, higher sensitivity, smaller size, lower power consumption and better stability.

Compared with other types of pressure sensors, piezoelectric pressure sensors have the advantages of fast response speed, wide measurement range and high measurement accuracy, which are particularly suitable for industrial automation occasions that require fast response and high-precision measurement.

When selecting a piezoelectric pressure sensor for industrial automation applications, it is necessary to consider factors such as measurement range, accuracy, stability, response time, working environment, and select according to specific application scenarios.

Piezoelectric pressure sensors are mainly used to measure seawater pressure in marine engineering, providing basic data for marine dynamics research, marine engineering safety monitoring, underwater navigation and positioning, etc.

Piezoelectric pressure sensors use the piezoelectric effect to convert the pressure exerted by seawater on its diaphragm into an electrical signal, thereby realizing the quantitative measurement of pressure. This sensor has the characteristics of high precision, high sensitivity and fast response.

The measurement range of piezoelectric pressure sensors depends on their design and manufacturing specifications. In marine engineering, it is usually necessary to select the appropriate sensor model and range according to the actual measurement needs to ensure the accuracy and reliability of the measurement results.

In marine engineering, piezoelectric pressure sensors may face challenges from harsh environmental conditions such as high pressure, strong corrosion, and low temperature. In addition, the complexity of the marine environment may also cause the sensor to be disturbed by shock, vibration, etc., affecting its measurement accuracy and stability.

Improving the stability and reliability of piezoelectric pressure sensors in marine engineering can be achieved by optimizing sensor design, using high-performance materials, strengthening packaging protection, and regular calibration and maintenance. In addition, sensor models with characteristics such as corrosion resistance and high pressure resistance can also be selected to meet the special requirements of the marine environment.

The accuracy of piezoelectric pressure sensors depends on their manufacturing and calibration process. In marine engineering, to ensure the accuracy of the sensor, a sensor model with high accuracy and stability should be selected, and calibration and verification should be performed regularly. At the same time, during use, care should be taken to avoid interference factors such as excessive impact and vibration on the sensor.

Piezoelectric pressure sensors play an important role in marine scientific research. It can monitor the pressure changes in the ocean in real time and provide reliable data support for marine meteorological forecasts, marine disaster warnings, marine resource exploration and other fields. In addition, piezoelectric pressure sensors can also be used to study the pressure distribution and changes in marine ecosystems, providing a scientific basis for marine ecological protection.

With the continuous development of marine engineering technology, the application prospects of piezoelectric pressure sensors in marine engineering are becoming more and more broad. In the future, piezoelectric pressure sensors will develop in the direction of higher accuracy, higher sensitivity, smaller size, lower power consumption and better stability to meet the higher demand for pressure measurement in marine engineering. At the same time, with the popularization and application of technologies such as the Internet of Things and big data, piezoelectric pressure sensors will also be interconnected with other sensors and equipment to provide more comprehensive support for the intelligence and automation of marine engineering.

Piezoelectric pressure sensors are mainly used in biomedicine to monitor physiological parameters, such as heart rate, pulse, blood pressure, respiratory rate, etc. In addition, they are also used for disease prevention and control and detection of biomarkers, such as the detection of epidemic viruses such as new coronary pneumonia.

The working principle of piezoelectric biosensors is based on the piezoelectric effect. When a piezoelectric material is subjected to an external force, the positive and negative charge centers inside it will be relatively displaced, thereby generating an electric potential difference, namely the piezoelectric effect. In biomedical applications, this effect is used to convert pressure changes in the body into electrical signals, thereby realizing the monitoring of physiological parameters and the detection of diseases.

Piezoelectric materials commonly used in piezoelectric biosensors include inorganic piezoelectric materials (such as quartz crystals, lead zirconate titanate piezoelectric ceramics, zinc oxide, etc.), organic piezoelectric materials (such as polyvinylidene fluoride, etc.) and biological piezoelectric materials (such as DNA membranes, DNA chains and peptides, etc.).

In heart rate and pulse monitoring, piezoelectric biosensors are usually fixed to key parts of the body (such as wrists, chest, etc.). When the heart beats or the pulse beats, the pressure changes will act on the piezoelectric material on the sensor, causing the piezoelectric material to generate electrical signals. After processing and analysis, these electrical signals can accurately reflect the values ​​of heart rate and pulse.

In blood pressure monitoring, piezoelectric biosensors can accurately record blood pressure and pulse waveforms by detecting electrical signals generated by arterial walls. This type of sensor is often used in surgery and critical care to provide doctors with accurate blood pressure data.

The application of piezoelectric biosensors in disease prevention and control is mainly reflected in the detection of biomarkers and epidemic viruses. By modifying the bioactive molecules (such as antibodies, DNA, etc.) fixed on the surface of the piezoelectric material, the sensor can specifically identify and bind to the object to be tested, thereby causing a change in the oscillation frequency. This change can be converted into an electrical signal and analyzed, thereby achieving early warning and diagnosis of the disease.

Compared with other biosensors, piezoelectric biosensors have excellent characteristics of good stability, fast detection speed, high accuracy and simple operation. In addition, they also have high sensitivity and selectivity, and can accurately identify and detect target molecules in complex biological environments.

With the continuous development of biomedical technology, the application prospects of piezoelectric biosensors in biomedicine are becoming more and more broad. In the future, piezoelectric biosensors will develop in the direction of higher sensitivity, higher stability, smaller size and lower power consumption. At the same time, with the continuous emergence of new materials and new technologies, the performance of piezoelectric biosensors will continue to improve, providing more accurate and reliable detection methods for the biomedical field.

Piezoelectric pressure sensors are mainly used in traffic systems for vehicle speed measurement, load bearing, vehicle model identification, and red light running photography.

Piezoelectric pressure sensors measure the pressure changes generated when the tire passes through the sensor and convert them into electrical signals. When the vehicle tire passes through multiple sensors in sequence, the speed of the vehicle can be calculated based on the time difference between the tire passing each sensor and the distance between the sensors.

Piezoelectric pressure sensors can measure the pressure of the vehicle tire on the ground, thereby inferring the weight of the vehicle. This is of great significance for traffic management, road maintenance, and overload detection.

Piezoelectric pressure sensors can identify the number of axles, wheelbase and other parameters of the vehicle by measuring the pressure distribution and changes generated when the vehicle passes, and then infer the type of vehicle. This is very useful for traffic flow analysis, road planning, and vehicle management.

In red light camera systems, piezoelectric pressure sensors can be used as triggers. When the front wheel of the vehicle passes the sensor, the sensor will send a signal to start the camera to take pictures. This helps to record red light violations and improve the efficiency of traffic management.

Piezoelectric pressure sensors have the advantages of high precision, high sensitivity, fast response and good stability. They can accurately measure pressure changes in complex traffic environments and convert them into reliable electrical signals. In addition, piezoelectric pressure sensors are small in size, light in weight, easy to install and maintain, and are very suitable for use in traffic systems.

With the continuous development of intelligent transportation systems, the application prospects of piezoelectric pressure sensors in traffic systems are becoming more and more broad. They can be used for traffic flow monitoring, road condition assessment, vehicle management, and traffic law enforcement, providing more accurate and reliable data support for traffic management and planning. At the same time, with the continuous advancement of technology and the reduction of costs, the application of piezoelectric pressure sensors in traffic systems will be more extensive and in-depth.