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Accelerometer and gyroscope are two kinds of sensors commonly used in vibration monitoring of structures. They all measure changes in vibration or displacement by sensing changes in an object’s acceleration or angular velocity. But there are some differences in how they work and how they are applied. The following will be a detailed introduction to the role and differences between accelerometers and gyroscopes.

The function and principle of accelerometer

The accelerometer is used to measure acceleration. A triaxial accelerometer can be used to measure the motion of a fixed platform relative to the earth’s surface, but once the platform moves, the situation becomes more complex. For example, the ER-3QA-02E is a high-performance three-axis accelerometer with digital output, high precision installation error, temperature compensation, and low power consumption.If the platform is free falling, the accelerometer measured the acceleration value is zero. If the platform is moving in a certain direction, the acceleration values of each axis will contain the acceleration value generated by gravity, so that the true acceleration value cannot be obtained. For example, the triaxial accelerometer mounted on the 60-degree roll Angle plane will measure the vertical acceleration value of 2G, whereas in fact the plane’s surface is about 60 degrees. Therefore, using the accelerometer alone cannot keep the aircraft in a fixed course.

The function and principle of gyroscope

Gyroscope measures the rate of rotation of the body around an axis. When the gyroscope is used to measure the rotation Angle of the aircraft’s body axis, if the plane is rotating, the measured value is non-zero, and the value of the measurement is zero when the plane is not rotating. Therefore, the angular velocity value of the gyroscope measured at the 60-degree roll Angle is zero, and the angular rate is zero when the plane is flying in a straight line. The current roll Angle can be estimated by the time integral of the angular velocity value, provided there is no error accumulation. Gyroscope to measure the value of the drift with time, after a few minutes or a few seconds will be the additional error accumulation, and eventually lead to the current relative horizontal roll Angle to the plane completely wrong cognition. Therefore, the use of gyroscopes alone cannot maintain a particular course of the aircraft.

The difference between accelerometers and gyroscopes

Accelerometers and gyroscopes are both sensors used to sense changes in vibration or displacement of structures, but there are some important differences between them.

1. Different measurement methods

The accelerometer mainly measures the linear acceleration of the object, while the gyroscope mainly measures the angular acceleration and angular velocity of the object. Their measurement methods are different, so they are suitable for different vibration test occasions. The high performance quartz flexible accelerometer represented by ER-QA-03A adopts high quality quartz crystal to achieve high precision acceleration measurement and has extremely high reliability and stability. Its special flexible construction enables it to adapt to high acceleration applications under various environmental conditions, such as high temperature, high pressure and high vibration environments.

1. Different measurement directions

The accelerometer mainly measures the vibration acceleration of the structure in the x, y and z directions, while the gyroscope mainly measures the angular velocity of the object in the x, y and z axes. Therefore, they are suitable for vibration tests that are not coaxial upwards.

1. Different application fields

Accelerometers are mainly used in the field of structural vibration testing, while gyroscopes can be used in a wide range of object motion testing fields, such as drones, aerospace and so on.
In summary, accelerometers and gyroscopes are commonly used sensors for vibration testing of structures and motion testing of objects. They have their own characteristics and application range. Accelerometers are generally more commonly used than gyroscopes in vibration measurement applications, but in the measurement of angular displacement and velocity of objects, gyroscopes are more suitable.

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The acceleration sensor uses gravity acceleration and can be used to detect the tilt angle of the device, but it will be affected by the acceleration of the movement, making the inclination measurement not accurate enough, so it is usually necessary to use a gyroscope and a magnetic sensor to compensate. At the same time, the magnetic sensor also uses the geomagnetic field to measure the azimuth. When the current in the system changes or there is a magnetically conductive material around it, and when the device is tilted, the measured azimuth is not accurate. At this time, an acceleration sensor (tilt sensor) is required. ) and gyroscope.

There are two types of accelerometers: one is an angular accelerometer, which is improved by a gyroscope (angular velocity sensor). The other is a linear accelerometer.

By measuring acceleration due to gravity, you can calculate the tilt angle of the device relative to the horizontal plane. By analyzing dynamic acceleration, you can analyze how the device moves.

The acceleration sensor can detect the AC signal and the vibration of the object. When a person walks, a certain regular vibration will be generated, and the acceleration sensor can detect the zero-crossing point of the vibration, so as to calculate the number of steps taken by a person or by running. Thus, the displacement that a person moves is calculated. And using a certain formula can calculate the calorie consumption.Use the acceleration sensor to detect the vibration / shake amplitude of the handheld device, and lock the camera shutter when the vibration / shake amplitude is too large, so that the captured image is always clear.

In the application of accelerometers, quartz accelerometers are represented. Quartz accelerometers are made of quartz material, which has better performance than metal and high fatigue resistance. Therefore, this kind of accelerometer has higher accuracy, strong anti-disturbance ability, large measurement range and strong overload ability. At present, quartz accelerometers have been widely used in the measurement of various linear acceleration, vibration acceleration, speed, distance, angular velocity, angular displacement and other parameters. The following are the areas where it is commonly used:

Oil logging field

Quartz accelerometer is one of the many accelerometers with relatively simple structure, performance, volume and price advantages. Especially in the high temperature environment of drilling and logging, it is an acceleration sensor that has been tested by a lot of actual downhole work experience, and has high temperature and high reliability product characteristics. For example, ER-QA-03D quartz accelerometer designed for oil mining can work at a high temperature environment of 180℃ and the volume is only 25×21mm, its seismic resistance is 500-1000g 0.5ms, which has the advantage of overcoming complex environmental difficulties, so as to improve the efficiency of logging.

Inertial navigation system field

Inertial navigation system is an auxiliary navigation system that uses accelerometers and gyroscopes to measure the acceleration and angular velocity of objects, and uses computers to continuously estimate the position, attitude and velocity of moving objects. By detecting the acceleration and angular velocity of the system, the inertial navigation system can detect changes in position, speed and attitude. ER-QA-03A is a high-performance quartz accelerometer with zero bias stability of 10-50μg, scale factor of 15-50 PPM, and second-order nonlinearity of 10-30μg/g2, providing accurate data information for the system.

Aerospace field

Quartz accelerometers can achieve high precision acceleration measurement with extremely high reliability and stability. Its special flexible construction enables it to adapt to high acceleration applications under various environmental conditions, such as high temperature, high pressure and high vibration environments. For example, in addition to the zero-bias stability of 10μg, the scale factor and second-order nonlinearity of the ER-QA-01A can also reach 10 PPM and 10μg/g² respectively. It is a good choice in aerospace applications.

If you want to get more details about accelerometer,pls visit https://www.ericcointernational.com/accelerometer/

The role of accelerometer sensors

An accelerometer sensorYour text to link here... is an electronic device capable of measuring acceleration force, also known as an accelerometer. The accelerating force is the force that acts on an object as it accelerates, just like the Earth’s gravity, which is gravity. There are two kinds of accelerometers: one is the angular accelerometer, which is mainly improved by the gyroscope (angular velocity sensor). The other is a linear accelerometer. By measuring the acceleration due to gravity, the tilt Angle of the device relative to the horizontal plane can be calculated. By analyzing the dynamic acceleration, you can analyze the way the device moves. An acceleration sensor measures the acceleration generated by traction.

Classification of accelerometer sensors

There are many kinds of accelerometer sensors according to different ways, among which accelerometers can be divided into three categories of high precision, medium precision and low precision according to measurement accuracy. With the development of market demand and micro-acceleration sensors, MEMS accelerometers will be widely used in the field of medium and low precision, and the mechanical quartz flexible accelerometers are still mainly used in the field of high precision. Quartz flexible accelerometer, as a classic high-precision mechanical pendulum accelerometer, is one of the key components in the field of high-precision applications.

Application of accelerometer sensor

Aerospace field

Quartz accelerometers can achieve high precision acceleration measurement with extremely high reliability and stability. Its special flexible construction enables it to adapt to high acceleration applications under various environmental conditions, such as high temperature, high pressure and high vibration environments. For example, in addition to the bias stability of 10μg, the scale factor repeatability and class II non-linearity repeatability of the ER-QA-01AYour text to link here... can also reach 10 PPM and 10μg/g² respectively. It is a good choice in aerospace applications.
Inertial navigation system field

Inertial navigation system is an auxiliary navigation system that uses accelerometers and gyroscopes to measure the acceleration and angular velocity of objects, and uses computers to continuously estimate the position, attitude and velocity of moving objects. By detecting the acceleration and angular velocity of the system, the inertial navigation system can detect changes in position, speed and attitude. ER-QA-03AYour text to link here... is a high-performance quartz accelerometer with bias stability of 10-50μg, scale factor repeatability of 15-50 PPM, and class II non-linearity repeatability of 10-30μg/g², which can provide accurate data information for the system.

Oil logging field

Formation detection is a process that converts ground vibration into electrical signals. It is most widely used in oil exploration, but also in ground fracture detection, gas formation development, debris flow warning and VSP logging. The core component of the seismometer is the acceleration sensor. By measuring the acceleration in the vertical direction, the information about the frequency and amplitude of the vibration can be obtained. In order to obtain accurate data and overcome the high temperature working environment of oil drilling, the specially designed ER-QA-03D can work in a high temperature environment of 180℃ and the volume is only 25×21mm, its anti-shock is 500-1000g 0.5ms, and its advantages can overcome complex environmental difficulties. Greatly improve the efficiency of logging.
Industrial vibration detection field

With the continuous development of the Internet of Things and artificial intelligence technology, many manufacturing, rail transit, electric power, metallurgy, petrochemical and other industries have introduced intelligent operation and maintenance systems to achieve online monitoring and analysis of equipment, which can send an alarm to the monitoring system and deal with it in time when the state of equipment becomes abnormal. MEMES accelerometers are often used in this field, such as ER-MA-5Your text to link here... with a bias stability of 5μg, a scale factor repeatability of 300ppm, and class II non-linearity repeatability of 10-30μg/g2. The vibration signal is measured by acceleration sensors or vibration detection instruments and analyzed to determine the health status of the equipment. The use of MEMES accelerometers greatly improves the accuracy and timeliness of predictive maintenance and fault warning, and also avoids unnecessary production downtime and casualties.

Accelerometer is one of the most critical inertial instruments. Together with gyro, it forms the basis and core content of inertial technology. Its performance directly determines the accuracy of inertial system. Quartz flexible accelerometer, as an important instrument of inertial measurement, has the advantages of high precision, high long-term repeatability and suitable for micro acceleration measurement. It has been widely used in many fields such as aerospace, aviation, navigation, mining and drilling.

So How do the parameters affect the performance of the quartz accelerometer? We will take ER-QA-01A as an example to introduce important parameters of the quartz accelerometer.
Range and Resolution: The unit of the range is usually “g”. Ericco quartz accelerometer range is 20g, 50g, 80g, and so on. The range is inversely proportional to resolution. The wider the range, the smaller the resolution; Conversely, the narrower the range, the greater the resolution. The bigger the range, the better. You should choose the one that suits you best.

Bias repeatability: The typical tactical level accelerometer is 1.4 mg. The zero-bias repeatability of ER-QA-01A can reach 10μg, equivalent to 10^-3 of the tactical level, which can be used in Aerospace.

Scale factor: It refers to the value of electromagnetic torque current corresponding to unit gravitational acceleration. In theory, the scale factor is linear, but it is not so in practice and application. It has non-linear degree and positive and negative asymmetry. Therefore, important parameters, namely “scale factor repeatability” and “scale factor temperature coefficient”, are introduced into the performance index of accelerometer parameters. Its value directly reflects the application effect and navigation accuracy of the accelerometer, and is an important reference index of the performance of the accelerometer.

Scale factor repeatability: under the same conditions and within a specified interval, the consistency between the scale factors of the quartz accelerometer is repeatedly measured. Expressed as the ratio of the standard deviation of the scale factor obtained by each test to its mean value in ppm. ER-QA-01A has a scale factor repeatability of up to 10ppm, representing the advanced level of quartz accelerometers for civilian use.

Vibration: The larger the value, the better. The larger the value, the stronger the vibration. ER-QA-01 has a seismic capability of 8grms at 20-2000Hz.

Shock: ER-QA-01 is also great for shock resistance, reaching 120g, 4.5ms, 1/2 sin.

Operating temperature: The wider the temperature range, the more suitable for harsh environments. The temperature range of ER-QA-01A is -45-80℃. Ericco also has special quartz accelerometers resistant to high temperature: ER-QA-03D and ER-QA-03F, which are suitable for the lowest temperature can reach -55℃, and the highest can reach 180℃.

Size: Ericco’s three hot sale quartz accelerometers, with diameters of 25.430mm and 18.223mm, you can choose the right size according to your needs.

The accelerometer industry will be steadily driven by the growth of drones, intelligent robots, automatic navigation, smart cars, mobile phones, smart watches, etc. With the new technological update of the accelerometer product, the price of the accelerometer is also reduced, which further expands its market share and greatly improves the visibility of consumers. In the next few years, with the development of social science and technology, the accelerometer industry will usher in unprecedented prosperity. With the continuous progress of science and technology, the accelerometer industry is expected to achieve breakthrough progress and rapid development in the next few years.

If you still have questions about the parameters or would like more information about the Ericco quartz accelerometer, please feel free to contact us: [email protected]

1.Accelerometer

Accelerometer (Accelerometer, G-Sensor), also called gravity sensor, can actually sense the acceleration in any direction (the acceleration of gravity is only the acceleration in the vertical direction of the surface), and the accelerometer measures the force of the component in a certain axis. To get the result, the form is the acceleration magnitude and direction (XYZ) of the axial direction, which is similar to the gyroscope, but the gyroscope pays more attention to its own rotation (in situ motion), and the accelerometer is mainly a measurement device The force situation of , that is, the three-axis motion situation, although the accelerometer may also convert the angular velocity in a small range, but the design principle seems to be more suitable for spatial motion judgment.

2.Gyroscope

The gyroscope (Gyroscope, GYRO-Sensor) is also called the ground sensor. The traditional structure is that there is a gyroscope inside, as shown in the figure below (three-axis gyroscope). The angle between the vertical axis and the device is calculated, and the angular velocity is calculated, and the motion state of the object in the three-dimensional space is judged by the angle and angular velocity. The three-axis gyroscope can simultaneously measure 6 directions including up, down, left, right, front and rear (the composite direction can also be decomposed into three-axis coordinates), and finally the movement trajectory and acceleration of the device can be determined. That is to say, the gyroscope judges the current motion state of the device by measuring its own rotation state, whether it is forward, backward, up, down, left or right, whether it is accelerating (angular velocity) or decelerating (angular velocity), All can be achieved, but to determine the orientation of the device (east, west, north and south), there is no way for the gyroscope to do so.

The traditional gyroscope is mechanical. With the development of technology, there are also vibrating gyroscopes, laser gyroscopes, micro-electromechanical mechanical gyroscopes, etc., both in terms of volume miniaturization, measurement accuracy and ease of use. improve.

3.Magnetometer

Magnetometer (Magnetic, M-Sensor) is also called geomagnetism and magnetic sensor. It can be used to test the strength and direction of the magnetic field, and to locate the orientation of the device. The principle of the magnetometer is similar to that of the compass. upper angle. So, the gyroscope knows “we turned around”, the accelerometer knows “we went a few more meters forward”, and the magnetometer knows “we are heading west”.

Therefore, in practical applications, due to the needs of application, error correction, and error compensation, the above sensors are often used in combination to make full use of the characteristics of each sensor to make the final calculation result more accurate. For example, in Android, the magnetometer and The accelerometer is used to calculate the Orientation, and the calculated orientation information needs to be obtained by combining the magnetic field direction and directional movement at the same time.

Distinguish and compare

1.Conceptual comparison

A gyroscope is a gyroscope inside, and its axis is always parallel to the initial direction due to the gyroscopic effect, so that the actual direction can be calculated by the deviation from the initial direction. The gyroscope in a mobile phone is actually a very sophisticated chip that contains an ultra-tiny gyroscope inside.

The accelerometer is used to detect the magnitude and direction of the acceleration received by the mobile phone. When the mobile phone is stationary, it is only subjected to the acceleration of gravity. Therefore, many people call the accelerometer function the gravity sensing function.

A magnetometer measures the strength and direction of the magnetic field

2.Principle comparison

Gyroscope measurements are referenced to a gyroscope that rotates in a direction perpendicular to the ground in the center of the interior. The result is obtained by the angle between the device and the gyro.

Accelerometers derive results by internally measuring the force in all directions of the component.

The principle of the magnetometer is the compass involved in high school physics

3.Application comparison

A gyroscope’s strength lies in measuring the rotational motion of the device itself. Better at the movement of the device itself. But the orientation of the device cannot be determined.

The strength of the accelerometer is in measuring the force on the device. Better at the movement of the device relative to an external reference (eg, the ground). However, when it is used to measure the position of the equipment relative to the ground, the accuracy is not high.

The magnetometer’s strength lies in locating the device’s orientation. The angle between the current device and the four directions of the south, east, north and west can be measured.

Combination suits

Triaxial sensor

① Three-axis accelerometer

The three-axis accelerometer works based on the basic principle of acceleration. Acceleration is a space vector. On the one hand, to accurately understand the motion state of an object, the components on its three coordinate axes must be measured; When the direction of movement of the object is known, only the three-axis acceleration sensor is used to detect the acceleration signal.

Since the three-axis accelerometer is also based on the principle of gravity, the three-axis accelerometer can achieve a double-axis plus and minus 90 degrees or a double-axis 0-360 degree inclination. After correction, the accuracy is higher than that of the double-axis accelerometer. Greater than the measurement angle is 60 degrees.

Advantages: The advantage of the three-axis acceleration sensor is that only the three-dimensional acceleration sensor is used to detect the acceleration signal when the direction of movement of the object is not known in advance. The three-dimensional acceleration sensor has the characteristics of small size and light weight, can measure the acceleration in space, and can fully and accurately reflect the motion properties of the object.

② Three-axis gyroscope

Three-axis gyroscope: Simultaneously measure the position, movement trajectory and acceleration in 6 directions. A single-axis can only measure quantities in two directions, that is, a system requires three gyroscopes, and one of the three-axis can replace three single-axis.

Advantages: The three-axis gyroscope is small in size, light in weight, simple in structure, good in reliability, more sensitive and more accurate.

③ Three-axis magnetometer

Three-axis geomagnetometer, also known as electronic compass, is widely popularized and applied in drones, smart watches, and navigation equipment.

In response to the need to detect changes in the movement of objects, the three-axis magnetic sensor carries a crucial absolute pointing function, escorting various functions such as stable flight and auxiliary navigation. As such, the reliability of the three-axis magnetic sensor is the cornerstone of the stable operation of these devices.
Six-axis sensor

Six-axis sensor usually refers to three-axis gyroscope + three-axis accelerometer. Nine-axis sensor

Nine-axis sensor usually refers to three-axis gyroscope + three-axis accelerometer + three-axis geomagnetometer, there are also six-axis accelerometer + three-axis gyroscope, and there are also six-axis gyroscope + three-axis accelerometer.

As an integrated sensor module, the nine-axis sensor reduces the circuit board and overall space, and is more suitable for use in lightweight and portable electronic devices and wearable products. In addition to the accuracy of the device itself, the data accuracy of the integrated sensor also involves correction after welding and assembly, as well as matching algorithms for different applications. Appropriate algorithms can fuse data from multiple sensors, making up for the insufficiency of a single sensor in calculating accurate position and orientation, enabling high-precision motion detection.

The accurate and real-time measurement of attitude parameters is a prerequisite for the realization of steering control of drilling tools. However, when the guide shaft is in rotation and vibration environment, the output of the inertial sensor measuring the attitude of the guide tool will be affected by the rotational centrifugal acceleration and vibration acceleration, which will distort the measurement signal, increase the Angle measurement error, and lead to the Angle uncertainty.It is very difficult to maintain the long-term use of the inclination probe in the actual working vibration environment of well logging. ERICOO’s high-temperature accelerometers currently are all quartz flexible accelerometers, which have strong anti-interference ability, good dynamic performance and measurement accuracy. High features, while enhancing stability and service life.

Quartz flexible accelerometer is a single-axis gravity accelerometer, which is characterized by simple structure, small volume, high precision and sensitivity, and high reliability.

The working principle of the quartz flexible accelerometer is that when the inertial mass is subjected to external acceleration, the relative position is slightly shifted, causing the change of the distance between the differential capacitor plates and the change of the differential capacitance. The servo amplifier detects this change and outputs the corresponding current, which is sent to the coil located inside the magnetic field to generate a feedback torque that is balanced with the input acceleration torque, and the inertial mass returns to the equilibrium position again. By measuring this current signal, the input acceleration can be calculated.

The quartz flexible accelerometer consists of a meter head and a servo circuit. The quartz flexible accelerometer used in the inclinometer probe is innovatively optimized for the meter head and the servo circuit.

The meter head includes proof mass assembly, upper torquer assembly and upper torquer assembly. Among them, the main problem that affects the high temperature working life is the connection between the terminal and the gold-plated film of the quartz pendulum. Generally, the method adopted by the manufacturer is to connect by soldering. Because of the problem of tin corrosion of the gold film, the high temperature working life and anti-vibration ability will be affected. Influence. The difference from ordinary quartz watch heads is that gold wire bonding is used to connect the IC chip to the package pins to enhance reliability and life.

The servo circuit consists of a differential capacitance detector, an integrator, and a compensation amplifier. ERICCO’s high-temperature quartz accelerometer ER-QA-03D improves the performance for long-term reliability in a 175° high temperature working environment. Compared with ordinary plastic packaging process chips, the multi-chip module thick-film hybrid integrated circuit process is used to solve the problem of not being able to work for a long time in a high temperature environment of 175°. In addition, the accelerometer uses a temperature sensor, which the operator can use to compensate Bias and Scale factor parameters to reduce the influence of temperature factors.

Accelerometer sensors are mainly used in drilling inclinometer system and continuous inclinometer system of oil drilling to measure the slope of drilling. When observing with a clinometer, the probe moves from the bottom of the clinometer tube to the top, pauses and measures the tilt at a distance of half a meter. The tilt of the probe is measured by two balanced servo accelerometers. An accelerometer measures the longitudinal position of the groove of the inclinometer tube, that is, the inclination of the plane on which the inclinometer probe is located. The other accelerometer measures the inclination perpendicular to the plane of the wheel. The inclination can be converted into lateral displacement. Comparing the current and initial observational data, it is possible to determine the amount of lateral migration change and show the movement displacement occurring in the formation. Plotting the change in the offset gives a high resolution displacement profile. This profile helps determine the magnitude, depth, direction, and rate of ground motion displacement.

As industrial equipment is generally digitalized and interconnected, Industry 4.0 has been realized and is helping to transform production tools. It is like a game-changer, making the production chain more flexible, supporting the manufacturing of customized products, while maintaining profitability. In addition, digital and industrial Internet of Things connections are also of great benefit to maintenance. After using sensors, especially quartz accelerometers, you can analyze the running state of the machine, instead of replacing worn parts at regular intervals. In the framework of predictive maintenance, operators need to intervene only when some early warning symptoms occur. This analysis of machine health is called condition-based monitoring (CbM), which can control the maintenance cost compared with the systematic maintenance system based on the usually very conservative fixed schedule. In addition to the more flexible maintenance operation plan, it can also detect problems at the early stage, so that operators can arrange the downtime of the machine accordingly. This is obviously much better than the downtime outside the production line.

Vibration analysis: the importance of sensors

The manufacturer uses a variety of parameters to determine the time to start the maintenance operation, including vibration, noise, temperature measurement, etc. Among the measurable physical quantities, vibration spectrum measurement can provide the most information for the root causes of problems in rotating machines (engines, generators, etc.). Abnormal vibration may be caused by ball bearing failure, shaft deviation, imbalance, excessive looseness, etc. Each problem has its own unique symptoms, such as the vibration source of rotating machines.

Vibration measurement with accelerometer

Vibration measurement can be carried out using an accelerometer placed near the monitored element. This kind of sensor can be piezoelectric or MEMS type. The latter has more advantages. It can not only provide better response at low frequency, but also has small size.ER-MA-5 High Accuracy MEMS Accelerometer is an inertial sensor, which can measure the linear acceleration due to gravity. MEMS accelerometer has the characteristics of small volume, light weight and low energy consumption that can be widely used in vibration detection, attitude control, security alarm, consumer applications, motion recognition and status recording. Accelerometers are combined with gyroscopes and magnetometers to create IMU (inertial measurement units).

When the ball bearing breaks down, every time the ball touches the crack, or touches the defect position of the inner or outer ring, it will hit, cause vibration, and even cause the rotating shaft to shift slightly. The frequency of impact is determined by the rotation speed and the number and diameter of the ball.

But this is not all! Once the fault occurs, the impact mentioned above will sometimes produce audible sound, namely shock wave, which is characterized by low energy spectral component and relatively high frequency, usually greater than 5 kHz, and always far more than the basic rotation frequency. Only low-noise and high-bandwidth accelerometers can measure the spectrum line corresponding to the first fault signal. These accelerometers can provide some valuable information for problems that cannot be detected by products with low frequency response or high noise. As the problem worsens, the low energy spectral components continue to increase. At the later stage, the entry-level accelerometer can detect the vibration, but at this time, it will become urgent to solve the fault, and the maintenance team needs to respond in a short time. In order to avoid being caught off guard, it is very important to use low-noise, high-bandwidth accelerometers to detect when the initial abnormality occurs.

ER-QA-03A High Performance Quartz Accelerometer bandwidth is 800~2500Hz, the volume of 25.4X30 mm, weight 80G，with high reliability is mainly used in inertial measurement and test systems in the aerospace and aviation fields. It can carry out static test and dynamic test, which is a standard vibration sensor.

Ericco is a manufacturer of quartz accelerometers, providing various acceleration solutions. The products can be customized. If you want more technical data and quotations, please feel free to contact us.
Web: Choosing a Good Quartz Accelerometer is Easier to Maintain-Ericco China [ericcointernational.com]

Strapdown inertial navigation system has the advantages of complete autonomy, no interference, real-time output of carrier attitude, position, speed and other navigation information, which has been widely valued by various countries in the military and civilian fields, especially in the military field, and is widely used in various missile and satellite launches. Therefore, its accuracy is one of the important symbols to measure the inertial navigation system. There are many factors that affect the accuracy of the strapdown inertial navigation system, such as the measurement accuracy of the inertial device, the algorithm of attitude solving and the speed of signal processing. Under the condition of the same algorithm selection and hardware implementation speed, the error compensation of gyroscope and accelerometer of inertial devices is particularly important. Among many factors affecting the output accuracy of inertial devices, temperature is the most significant and common factor.Compared to other accelerometers, the ER-QA-03D quartz accelerometer can withstand the operating ambient temperature of -55~180 ° C, and the bias repeatability is <50μg, and the nominal repeatability is <80 ppm.

The working principle of quartz flexible accelerometer

Quartz flexible accelerometer is a kind of force balance accelerometer, which is composed of two parts: the meter head and the servo circuit. The flexible pendulum plate and torque coil constitute a mass block sensitive to acceleration. When the acceleration input, the flexible pendulum plate deviates from the equilibrium position, at this time, the moving plate connected with the flexible pendulum plate also deviates from the original position, this deviation is detected by the differential capacitance sensor and converted into a current signal output, and then fed back to the torque part of the constant magnetic field, thus generating a balance force. Forcing the flexible pendulum to deflect to the original equilibrium position, the magnitude of the current is proportional to the magnitude of the acceleration, and the magnitude of the acceleration can be detected by detecting the magnitude of the current. The bias repeatability of ER-QA-01A produced by this principle is less than 10μg, the standard factor repeatability is less than 10 ppm, and the second-order nonlinear repeatability is 10μg/g², which makes it the best choice for high-precision inertial navigation systems.

Temperature drift analysis of quartz flexible accelerometer

Inertial devices, including gyroscopes and accelerometers, are affected by temperature in practical applications, mainly in two aspects: one is the sensitivity of the inertial device itself to temperature, and the other is the influence of the temperature field around the device, that is, the temperature gradient and the thermal gradient around the shell will cause errors. The thermal expansion and cold contraction of the material will cause the deformation of the instrument structure parts and the change of the physical parameters of various materials inside, which directly affects the output stability.

In order to reduce and compensate the influence of temperature on the accuracy of the quartz accelerometer and its system, the methods often used are:
1. Development of temperature-insensitive inertial devices. Starting from the thermal design of the inertial device, the layout of the device, the material and the structural shape of the parts meet the requirements of temperature insensitive.

1. Materials and components with negative temperature coefficient are added to the structure to offset the changes in other related material physical parameters caused by temperature changes and compensate the influence of temperature on the accuracy of the inertial device.
   This is just an article sharing link, if you want to get more content, please click here：What Effect Does Temperature Have on Quartz Flexible Accelerometer? - Ericco Inertial System [ericcointernational.com]

The working principle of high performance quartz accelerometer

High performance accelerometer is one of the devices for measuring linear acceleration of objects based on Newton’s second law in inertial system. In the acceleration process of the sensor, the acceleration value is calculated by measuring the inertial force of the mass block, and the linear velocity can be obtained by integrating the time with the known initial velocity, and the linear displacement can be calculated by integrating again. The product structure of the accelerometer is to use the sensitive structure to convert the change of linear acceleration into the change of capacitance, and finally read the change of capacitance value through the application-specific integrated circuit, so as to measure the acceleration value of the movement of the object.

Classification of high performance quartz accelerometers

According to performance, quartz acceleration can be scored into consumer level, tactical level and navigation level. ER-QA-03A, as one of the representative products of high-performance quartz accelerometers, has a zero bias stability of 10-50μg, a measurement range of ±50g and a scale factor repeatability of 15-50 PPM. Whether it is from zero bias stability or measurement range, it has high applicability. In addition, the performance indicators of this product are high measurement accuracy, good repeatability, high reliability, small size, light weight, wide voltage power supply, low power consumption. High-performance quartz accelerometers can measure the well trajectory and the actual position of the bit in the field of resource exploration drilling and production, so as to ensure that the well depth reaches the predetermined position. In particular, the oil exploration industry has higher requirements for slope and orientation measurement, and ER-QA-03A can also accurately complete the data measurement task.
Structure of high performance quartz accelerometer

The quartz accelerometer is composed of yoke iron and soft magnetic material with low temperature coefficient and good magnetic permeability, and the magnetic steel is processed by grinding machine with permanent magnet material with good magnetic permeability. The material of the flexible sheet is quartz glass with excellent temperature performance, and the shape is made of ultrasonic processing. The processing of the flexible element is generally carried out by chemical corrosion method, and the whole flexible sheet can also be processed by reactive ion etching process.

Application of high performance quartz accelerometer

With the development of science and technology, inertial navigation system has increasingly higher requirements for accelerometer performance, requiring accelerometers with small size, low cost, high precision and high reliability. Quartz accelerometers obviously meet these requirements, so it has a broad application prospect in the field of inertial navigation. In the field of aerospace, quartz flexible accelerometers can be used in aerospace high-precision navigation systems, attitude control and flight attitude control. With the improvement of the performance requirements of different motion systems, accelerometer is an important tool to study the flutter and fatigue life of various aircraft in flight tests. Therefore, the linear accelerometer can be installed in the moving object to directly measure its acceleration, and then get the speed and position, the measurement accuracy is high, the dynamic performance is good, far better than the air speedometer, odometer.

In safety applications, the fast response of accelerometers is very important. Acceleration sensors can be used in safety performance such as automotive airbags and anti-traction control systems. When the airbag should be deployed needs to be determined quickly, so the accelerometer must respond in a split second. The response time of the device can be reduced by using a sensor design that can quickly reach a steady state rather than a vibration. Among them, piezoresistive acceleration sensors are developing the fastest due to their wide application in the automotive industry.

In the mechanical field, it can be used for vibration analysis and mechanical fault diagnosis; In earthquake research, it can be used for map construction and earthquake prediction. With the emphasis on safety and predictability, the market demand for quartz flexible accelerometers will further increase.
The article is derived from this link：What can you do with an Accelerometer? - Ericco Inertial System [ericcointernational.com]

The working principle of high performance quartz accelerometer

High performance accelerometer is one of the devices for measuring linear acceleration of objects based on Newton’s second law in inertial system. In the acceleration process of the sensor, the acceleration value is calculated by measuring the inertial force of the mass block, and the linear velocity can be obtained by integrating the time with the known initial velocity, and the linear displacement can be calculated by integrating again. The product structure of the accelerometer is to use the sensitive structure to convert the change of linear acceleration into the change of capacitance, and finally read the change of capacitance value through the application-specific integrated circuit, so as to measure the acceleration value of the movement of the object.

Classification of high performance quartz accelerometers

According to performance, quartz acceleration can be scored into consumer level, tactical level and navigation level. ER-QA-03A, as one of the representative products of high-performance quartz accelerometers, has a zero bias stability of 10-50μg, a measurement range of ±50g and a scale factor repeatability of 15-50 PPM. Whether it is from zero bias stability or measurement range, it has high applicability. In addition, the performance indicators of this product are high measurement accuracy, good repeatability, high reliability, small size, light weight, wide voltage power supply, low power consumption. High-performance quartz accelerometers can measure the well trajectory and the actual position of the bit in the field of resource exploration drilling and production, so as to ensure that the well depth reaches the predetermined position. In particular, the oil exploration industry has higher requirements for slope and orientation measurement, and ER-QA-03A can also accurately complete the data measurement task.
Structure of high performance quartz accelerometer

The quartz accelerometer is composed of yoke iron and soft magnetic material with low temperature coefficient and good magnetic permeability, and the magnetic steel is processed by grinding machine with permanent magnet material with good magnetic permeability. The material of the flexible sheet is quartz glass with excellent temperature performance, and the shape is made of ultrasonic processing. The processing of the flexible element is generally carried out by chemical corrosion method, and the whole flexible sheet can also be processed by reactive ion etching process.

Application of high performance quartz accelerometer

With the development of science and technology, inertial navigation system has increasingly higher requirements for accelerometer performance, requiring accelerometers with small size, low cost, high precision and high reliability. Quartz accelerometers obviously meet these requirements, so it has a broad application prospect in the field of inertial navigation. In the field of aerospace, quartz flexible accelerometers can be used in aerospace high-precision navigation systems, attitude control and flight attitude control. With the improvement of the performance requirements of different motion systems, accelerometer is an important tool to study the flutter and fatigue life of various aircraft in flight tests. Therefore, the linear accelerometer can be installed in the moving object to directly measure its acceleration, and then get the speed and position, the measurement accuracy is high, the dynamic performance is good, far better than the air speedometer, odometer.

In safety applications, the fast response of accelerometers is very important. Acceleration sensors can be used in safety performance such as automotive airbags and anti-traction control systems. When the airbag should be deployed needs to be determined quickly, so the accelerometer must respond in a split second. The response time of the device can be reduced by using a sensor design that can quickly reach a steady state rather than a vibration. Among them, piezoresistive acceleration sensors are developing the fastest due to their wide application in the automotive industry.

In the mechanical field, it can be used for vibration analysis and mechanical fault diagnosis; In earthquake research, it can be used for map construction and earthquake prediction. With the emphasis on safety and predictability, the market demand for quartz flexible accelerometers will further increase.
The article is derived from this link：What can you do with an Accelerometer? - Ericco Inertial System [ericcointernational.com]

If you want to learn more about quartz accelerometers, click here：Quartz Accelerometer Manufacturer - ERICCO China [ericcointernational.com]