What are the Advantages of Tilt Sensor

The tilt sensor is a very accurate measuring tool for small angles. It can measure the inclination of the measured plane relative to the horizontal position, the parallelism and perpendicularity of the two components. It has become an indispensable and important measuring tool in bridge construction, railway laying, civil engineering, oil drilling, aviation and navigation, industrial automation, intelligent platform, mechanical processing and other fields.

1. The principle of tilt sensor

The working principle of the inclination sensor is based on microelectromechanical system (MEMS) technology and accelerometer principle. It is equipped with tiny accelerometers, and by using gravity, inertia and other mechanical principles, to detect the object’s tilt angle relative to the Earth’s horizontal plane.

When the object is at rest, the tilt sensor is subjected to gravity, which causes the accelerometer to align with the vertical direction of the Earth. When the object tilts, the direction of the accelerometer changes accordingly, resulting in an electrical output indicating the angle and direction of the object’s tilt.

2. Advantages of tilt sensor

The main benefits of tilt sensors include:

2.1 High Precision

The tilt sensor adopts MEMS technology, which has the characteristics of high precision, high stability and low noise, and can realize the high precision measurement and control of the tilt angle of the object. ER-TS-12200-Modbus is a high-precision wireless inclination sensor, its accuracy can reach 0.001°, using industrial MCU, three-proof PCB board, imported cables, wide temperature metal shell and other measures, its industrial design has extremely high measurement accuracy and anti-interference ability. It is suitable for remote real-time monitoring and analysis of industrial sites, dilapidated buildings, ancient buildings, civil engineering, tilt deformation of various towers and other needs.

2.2 Compact and Lightweight 

The tilt sensor is small in size, light in weight, easy to install and carry, and is suitable for various occasions and environments. ER-TS-32600-Modbus its volume is 94*74*64mm, weight is only 460g, very easy to install and carry. Is an ultra-low power consumption, small volume, high-performance wireless inclination sensor, it uses lithium battery power, based on the Internet of Things technology Bluetooth and ZigBee(optional) wireless transmission technology, it meets the needs of users in industrial applications without power supply or real-time dynamic measurement of object attitude angle.

2.3 High Reliability

The tilt sensor has high vibration resistance, impact resistance, water and dust resistance, and can run stably in complex environment for a long time. For example, the ER-TS-3160VO, which has a seismic resistance higher than 20000g, is adopted IP67 protection grade, it has the characteristics of strong shock and vibration resistance, especially suitable for a variety of harsh industrial environments.

Summary: With the continuous development of technology, inclination sensors will have wider prospects and advantages.

1. High precision and stability: With the continuous improvement of measurement accuracy and stability requirements in various fields, the future development direction of inclination sensors will be to improve the accuracy and stability of induction components.

2. Multi-functional: the inclination sensor will gradually develop in the direction of multi-functional, such as integrating the functions of gyroscopes, magnetometers and other sensors to achieve the measurement of a variety of parameters.

3. Intelligent: inclination sensor will be combined with artificial intelligence, internet of things and other technologies to achieve intelligent perception and data processing, improve application efficiency and user experience.

4. Miniaturization: In order to meet the application needs of some special scenarios, the volume of the inclination sensor will gradually shrink and develop in the direction of miniaturization.

5. Wide application: With the continuous progress of inclination sensor technology and the expansion of application scenarios, its application in various fields will be more extensive, bringing more convenience to people’s life and work.

How the MEMS Inertial Measurement Unit works？

 The inertial measurement unit is a device that measures the three-axis attitude angle (or angular rate) and acceleration of an object. Generally, an inertial measurement unit contains three single-axis accelerometers and three single-axis gyroscopes. The accelerometer detects the acceleration signals of the object in three independent axes of the carrier coordinate system, while the gyroscope detects the angular velocity signal of the carrier relative to the navigation coordinate system. Measure the angular velocity and acceleration of the object in three-dimensional space, and use this to calculate the attitude of the object. It has very important application value in navigation. IMUs are mostly used in equipment that require motion control, such as cars and robots. It is also used in situations where precise displacement calculations using attitude are required, such as inertial navigation equipment for submarines, aircraft, missiles and spacecraft.

The principle of an inertial measurement unit is very similar to taking small steps in the dark. In the dark, due to the error between your estimate of the step length and the actual distance traveled, as you take more and more steps, the difference between your estimated position and the actual position will become farther and farther. When taking the first step, the estimated position is relatively close to the actual position; but as the number of steps increases, the difference between the estimated position and the actual position becomes larger and larger. This method is extended to three dimensions, which is the principle of the inertial measurement unit.

The academic expression is: Based on Newton’s laws of mechanics, by measuring the acceleration of the carrier in the inertial reference system, integrating it over time, and transforming it into the navigation coordinate system, the velocity in the navigation coordinate system can be obtained. , yaw angle and position information.

Therefore, in layman’s terms, the inertial measurement unit is a strapdown inertial navigation system. The system consists of three acceleration sensors and three angular velocity sensors (gyros). The accelerometer is used to feel the acceleration component relative to the vertical line of the ground. The speed sensor is used to get a feel for the angle information.

It is worth noting that the inertial measurement unit provides relative positioning information. Its function is to measure the movement route of the object relative to the starting point, so it cannot provide information about your specific location. Therefore, it is often combined with GPS. Used together, when the GPS signal is weak in certain places, the IMU can play its role, allowing the car to continue to obtain absolute position information and not get “lost.”

If you want to purchase an IMU please contact us.

concate me：

website：https://www.ericcointernational.com/inertial-measurement-units

Email: info@ericcointernational.com
WhatsApp: +8613992884879

How to Improve the Long-term Stability of the Quartz Accelerometer?

 

Quartz accelerometer is an inertial navigation device that uses Newton’s second law (Law of inertia) to measure acceleration, and is widely used in aerospace, aviation, navigation, transportation, oil and other fields. Because of its simple structure, small size, high precision and sensitivity, good stability, low power consumption, low cost, it is more widely used in the space field of missiles and launch vehicles. From the perspective of various models, the long-term stability of quartz accelerometers has also become a bottleneck restricting the development of inertial systems. Therefore, this paper will briefly introduce how to improve the long-term stability of quartz accelerometer from the following points.

Factors affecting long-term stability

Influence factors of partial value

It can be seen from the important indexes that affect the stability of the quartz accelerometer that the size of the offset value and the long-term stability play an important role in its accuracy. For example, the bias of ER-QA-03A1 is 3mg, and the bias repeatability is 10μg, which has the attribute characteristics of high precision. According to the main reasons affecting the occurrence of bias, in the current technical state, according to the quartz accelerometer error model, the main reasons affecting the stability of the offset value are the zero change of the differential capacitance sensor (the size drift of the support structure) and the change of the elastic recovery Angle of the pendulum plate beam (the slow release of the processing stress and the structural stress), which cause the direct cause of the offset error.

Scale factor influencing factors

Calculation formula of scale factor K1: K1=P/KT=mL/ BlL

It can be seen from the formula that the stability of the scale factor is determined by the torque coefficient and the pendulum property. Further analysis is determined by the stability of the detection mass m, the working air gap magnetic induction intensity B, the effective length of the coil wire l, the distance from the detection mass center of mass to the pivot L and the distance from the electromagnetic force center to the pivot L. The change of the performance of the pendulum component and the instability of the scale factor of the torquer are the main reasons leading to the change of the accelerometer factor stability, that is, increasing the scale factor stability of the torquer can improve the scale factor stability of the accelerometer.

Concrete measures for long-term stability

Application of new high performance permanent magnets

The role of a permanent magnet is providing the magnetic induction in the formula. Theoretically, as long as the mass, length and magnetic induction intensity do not change, the current value can accurately calibrate the acceleration value. However, in general, the magnetic properties of permanent magnets change with temperature and time. The change of temperature directly determines the accuracy parameters of the accelerometer, and the drift of time directly limits the stability parameters of the accelerometer. Therefore, temperature and time are the two most important factors restricting the application of accelerometers. Under the premise of ensuring the remanent temperature coefficient, the coercive force temperature coefficient is also more than one order of magnitude lower than that of traditional magnets, which can effectively reduce the magnetic field drift caused by the fluctuation of coercive force field, and the magnetic field will show better temperature stability and time stability, which is expected to ensure the long-term stable use of quartz accelerometers in variable temperature environments.

Temperature compensation technique

Temperature is an important aspect that affects the accuracy of quartz accelerometer. The fluctuation of the operating temperature inside the inertial device and the thermal gradient around the shell will cause errors. The thermal expansion and cold contraction of the material will deform the structural parts of the accelerometer and cause interference torque to the accelerometer. Temperature changes will also change the physical parameters of various materials inside the device, and the change of magnetic properties of the torquer will also directly affect the measurement accuracy of the accelerometer, so the accuracy of the accelerometer can be improved through magnetic temperature compensation. At present, the products represented by ER-QA-01A3 have applied this technology to ensure its accuracy in long-term use.

Through the analysis of the factors affecting the long-term stability of the quartz accelerometer, it is realized that its stability is closely related to the energy of the pendulum material and the magnetic field stability of the torquer. The long-term stability is improved by using new high performance permanent magnets and temperature compensation technology.

The full text link:https://www.ericcointernational.com/application/how-to-improve-the-long-term-stability-of-the-quartz-accelerometer.html

Email : info@ericcointernational.com

 Whats app:13992884879

Inertial Measurement Unit Error Calibration

The inertial measurement unit (IMU) is an inertial measurement device composed of a three-axis accelerometer, a three-axis gyroscope, and a three-axis magnetic sensor. It is mainly used to measure the angular rate, acceleration, and magnetic heading of the aircraft’s three degrees of freedom. The navigation-grade MEMS IMU independently developed by ERICCO can independently seek north. It adopts MEMS design and system integration methods. This product has the advantages of light weight, small size, low cost, and high reliability, and has been widely used in military and civilian fields.

The measurement accuracy of the inertial measurement unit is not only related to the detection accuracy of the inertial measurement component itself, but also to the processing technology and installation accuracy. Therefore, the research on the calibration and error compensation of the inertial measurement unit is of great significance.

The calibration methods of the IMU mainly include the traditional multi-position and angular rate calibration method based on the turntable and the on-site multi-position calibration method. Based on the position calibration method, a gyro calibration method that eliminates the north misalignment is given. The traditional calibration method is based on a high-precision turntable, and the calibration process is very complicated. On-site calibration can not only reduce the workload, but also effectively improve the calibration accuracy. Another calibration method is to combine the traditional static multi-position and rate calibration method and propose a 6-position calibration method based on a dual-axis rotating mechanism. This method is more convenient to solve the scaling factor and installation error, but it has a few steps when solving the constant drift. More cumbersome.

Next, the error sources of the IMU unit will be analyzed. An improved calibration method based on accelerometer and gyroscope is proposed. To understand this improved calibration method, we need to first understand the error model and calibration method of the inertial measurement unit. It will be further introduced from the accelerometer and gyroscope.

1.Inertial measurement unit error model

As shown in Figure 1, OXnYnZn is the orthogonal coordinate system, OXbYbZb is the coordinate system of the inertial measurement unit, and the three axes of the ideal gyroscope and accelerometer are respectively installed on three orthogonal surfaces to form a right-handed coordinate system. However, due to the working principles and structures of gyroscopes and accelerometers, as well as integrated manufacturing and installation, the input coordinate axes of the accelerometer and gyroscope in the inertial measurement unit cannot be orthogonal, and there are 6 orthogonal coordinate systems. Installation error angles θxy, θxz, θyx, θyz, θzx, θzy. The purpose of sensor calibration is to compensate for the calibration factor between the output value and the measured value, to compensate for the zero offset error, and to compensate for the installation coupling error caused by machining accuracy, assembly technology, etc.

                                             Figure 1. Installation error angle in non-normal coordinate system

1.1Gyro error model

The gyro output data is affected by the orthogonality of the coordinate system, installation accuracy and ambient temperature, which will cause changes in the gyro’s zero bias, scale factor, installation error angle and noise. Therefore, the gyro’s output model is. Therefore, the gyro’s output model is One part is the measured angular velocity vector of the sensitive axis, and the other part is the real angular velocity vector, which will include a linear scale factor, a non-orthogonal matrix, a constant drift (zero bias), and a gyro noise error. Considering that it has a small impact on the calibration results, the noise is ignored. The impact of errors on calibration. Let K = I + Sω + Nω, then the formula can be expressed as:

Among them, Kyx and Kzx are the coupling coefficients of the installation error angles θxy and θxz of the sensitive axis xg. Kxy and Kzy are the coupling coefficients of the installation error angles θyx and θyz of the sensitive axis yg. Kxz and Kyz are the coupling coefficients of the installation error angles θzx and θzy of the sensitive axis zg. Coupling coefficients, Kxx, Kyy, Kzz are the calibration coefficients of the sensitive axes xg, yg, zg, Dωx, Dωy, Dωz are the constant drift (zero bias) of the gyro sensitive axes xg, yg, zg.

1.2 Accelerometer error model

The accelerometer output data is affected by the orthogonality of the axis system in the coordinate system, installation accuracy and ambient temperature, which will cause changes in the accelerometer’s zero bias, scale factor, installation error angle and noise, so the output model of the accelerometer is part of Measure the acceleration vector for the sensitive axis, and part of it is the true specific force vector, which will include nonlinear scaling factors, non-orthogonal matrix constant drift (zero bias), and gyro noise errors. Considering that it has a small impact on the calibration results, the noise is ignored The impact of errors on measurement results. Let C = I + Sa + Na, then the formula can be expressed as:

Among them, Cyx and Czx are the coupling coefficients of the installation error angles θxy and θxz of the sensitive axis xg. Cxy and Czy are the coupling coefficients of the installation error angles θyx and θyz of the sensitive axis yg. Cxz and Cyz are the coupling coefficients of the installation error angles θzx and θzy of the sensitive axis zg. Coupling coefficient, Cxx, Cyy, Czz are the calibration coefficients of the sensitive axes xg, yg, zg, Dax, Day, Daz are the constant drift (zero bias) of the accelerometer’s sensitive axes xg, yg, zg.

2.Calibration of inertial measurement unit

2.1 Gyro calibration method

The scale factor and installation error of the gyroscope can be calibrated by the multi-position method. In order to minimize the calibration state, make the sensitive axis of the gyroscope point east or west during initial calibration, then the component of the earth’s rotation rate in this axis is zero. Based on this principle, 4 states are selected from 24 states for gyro calibration. Rotate the inertial measurement unit to four different positions as shown in the figure below, record the output data of the three axial gyroscopes in sequence, and calibrate the zero bias, scale factor and installation error of the gyroscope.

2.2 Accelerometer calibration method

In its natural state, the accelerometer is not affected by any external force or angular velocity input except the acceleration of gravity and the rotation of the earth. The accelerometer calibration adopts the static multi-position calibration method. The IMU is rotated to 6 different positions as shown in the figure below, and the three-axis accelerometer output data output at each position is recorded in turn, and the zero bias and scale of the accelerometer are calibrated. factors and installation errors.

This article proposes a calibration method for low-cost inertial measurement unit zero bias, scale factor and installation error angle, which simplifies the calibration process and improves calibration efficiency. The calibration method was applied to the inertial measurement unit, which met the expected test requirements and verified the correctness and effectiveness of the compensation method. A scale factor temperature model and a zero-bias temperature model can be established to further improve the accuracy of calibration. The ER-MIMU-01 and ER-MIMU02 independently developed by our company (ERICCO) are calibrated using the above calibration method, which effectively improves the accuracy of the product. If you want to learn about and purchase IMU, please contact our technical staff.

The Advantages and Disadvantages of the Transmission Mode of Tilt Sensor

In today's industrial and commercial environment, tilt sensors are increasingly used to measure and monitor the tilt angle of equipment or structures. Depending on the data transmission method, inclination sensors can be divided into wired and wireless types. In this article, we'll delve into both types of tilt sensors, including the pros and cons, and how to choose the best solution for your specific needs.

1. Wired tilt sensor

Wired inclination sensor built-in high performance MCU built-in algorithm, through a high oversampling rate, improve the high frequency characteristics of the data, through the data filtering algorithm to remove unreasonable accidental error data, Kalman filter algorithm for higher precision data processing, suitable for monitoring the structure deformation monitoring field with high monitoring frequency requirements. Wired inclination sensors usually use RS485 bus or other similar bus protocols to transmit inclination signals. RS485 is a serial communication protocol widely used in the field of industrial automation, which has the advantages of noise suppression and high signal quality. ER-TS-3160VO is a linear inclination sensor with an accuracy of 0.01°, its cable standard length is 1.5m, and it can output RS232 at the same time, RS485 can be customized, the measurement range can reach 0~±180°, and the impact vibration resistance is strong.

The main advantage of the wired inclination sensor is that the signal stability is high, and the signal quality is not easy to be disturbed because of the wired transmission mode. In addition, wired sensors have a long service life, lower maintenance costs, and a lower failure rate. However, this sensor also has some disadvantages, such as the need to lay cables, high requirements for the field environment, may exist in some application scenarios wiring difficulties.

2. Wireless tilt sensor

Wireless inclination sensors have become more and more popular in recent years, and common wireless inclination sensors include NB-IoT wireless inclination sensors and LORO wireless inclination sensors. These sensors transmit tilt signals via wireless communication technology without cable connections, making them highly flexible.

The main advantages of wireless tilt sensors are their flexibility and convenience. Since no wiring is required, the sensor can be easily installed anywhere it is needed, without considering the laying of cables. In addition, wireless sensors also have the advantages of high mobility, easy expansion and maintenance. However, wireless sensors also have some disadvantages, such as signal quality may be affected by radio interference, and signal stability and reliability may not be as good as wired sensors. ER-TS-12200-Modbus is a high-precision tilt sensor using Bluetooth and ZigBee wireless transmission technology of the internet of things, eliminating the complicated wiring and noise interference caused by long cable transmission, using lithium battery power supply, good long-term stability, zero drift, can automatically enter low-power sleep mode, get rid of the dependence on the use of environment.

Generally speaking, the mass of the building structure is huge, and the rate of change of inclination is relatively small, and there is a development process. The sampling frequency of conventional structural health monitoring is not high, and once a day can meet the requirements. In this case, the choice of the wireless inclination sensors with its own battery is the most appropriate, and the installation is very convenient.

3. How to choose the most suitable tilt sensor for you

When choosing an inclination sensor, you need to consider the following factors:

(1) Application scenarios: Different application scenarios have different requirements for sensors. For example, in some scenarios where long-term stability measurements are required, wired sensors may be preferred; Some use cases, such as house monitoring, basically have 220V mains power in the field, and low cost wired tilt sensors can be used. Of course, for monitoring scenarios with high acquisition frequency requirements, choosing a wired inclination sensor is a wise choice. In scenarios that require flexible deployment, easy scaling and maintenance, wireless sensors may be more suitable.

(2) Signal quality: For some application scenarios that require high-precision measurement, such as precision equipment monitoring or large-scale structure monitoring, it is necessary to choose a wired sensor with higher signal quality. For some application scenarios with low precision requirements, such as logistics and transportation, agricultural monitoring, etc., wireless sensors may be enough to meet the needs.

(3) Cost and maintenance: For some application scenarios that require a large number of sensors to be deployed, such as large-scale facility monitoring or logistics tracking, the deployment and maintenance cost of wireless sensors may be lower. For some cost-sensitive scenarios, such as small device monitoring or small structure monitoring, the cost of wired sensors may be lower.

(4) Durability and reliability: For some scenarios that require long-term continuous operation, such as equipment monitoring and fault warning systems in petrochemical, electric power and other fields, it is necessary to choose wired sensors with higher durability and reliability. For some scenarios that require portable and temporary use, such as construction sites, agricultural monitoring, etc., wireless sensors will be more suitable.

In short, when choosing an inclination sensor, it is necessary to choose according to actual needs and specific scenarios. Both wired and wireless sensors have their own advantages and scope of application. Only by fully understanding the characteristics and application scenarios of various sensors can we make the most appropriate choice.

A tactical grade inertial measurement device

Today, microelectromechanical systems (MEMS) inertial sensors and inertial systems have become an indispensable development direction for future navigation technology. MEMS technology is widely used due to its advantages such as small size, light weight, low power consumption, low cost, and impact resistance. At present, the development of MEMS inertial technology is relatively mature. It forms a combined system with auxiliary systems such as gyroscopes and accelerometers to provide suitable solutions for most navigation applications. The inertial measurement unit developed by Ericco is divided into MEMS IMU and FOG IMU. MEMS inertial measurement units are divided into tactical grade and navigation grade. Navigation-grade IMUs can seek north independently, while tactical-grade inertial measurement units can rely on magnetometers or GNSS to find north. Below we will introduce and recommend an ERICCO tactical grade IMU.

Next, we mainly learn about a new inertial measurement unit — ERICCO INERTIAL SYSTEM tactical-grade inertial measurement unit: ER-MIMU03 (high-precision navigation/stability control MEMS IMU).

ERICCO launches tactical-grade inertial measurement unit (IMU): ER-MIMU03 uses high-quality and reliable MEMS accelerometer and gyroscope. Equipped with three-axis precision gyroscopes of (complement code) numerical temperature, angle, accelerometer hexadecimal temperature, acceleration hexadecimal complement); It can also output floating point dimensionless values of gyroscope and accelerometer data processed by underlying calculations. ). The IMU has a built-in acceleration sensor and gyroscope, which can measure linear acceleration and rotational angular velocity in three directions, and obtain the attitude, speed and displacement information of the carrier through analysis. Applications for this tactical-grade IMU include azimuth, attitude, position measurement and maintenance in GNSS-assisted INS. Heading, pitch, roll measurement in UAV AHRS Robot control and control of autonomous machines, UAV directional stabilization and control of satellite antenna pointing, target tracking system Guidance, navigation and control attitude and attitude IMU orientation in tactical MEMS weapon systems Corner retention and positioning. Motion survey and maintenance of MRU and other application areas.

The high-precision navigation/stability control MEMS IMU integrates a three-axis MEMS accelerometer and a three-axis MEMS gyroscope in a unique redundant design that maximizes performance while reducing device size.

In terms of performance specifications, the high-precision navigation/stability control MEMS IMU has excellent gyroscopes and accelerometers. The gyroscope has a bias instability of 0.3°/h. Achieve long-term dead reckoning and maintain excellent heading performance. The MEMS sensor in ER-MIMU03 has extremely low vibration correction errors and can withstand high vibration environments up to 6.06g.

With extremely low gyroscope bias instability, the navigation performance of the high-precision navigation/stability control MEMS IMU can work normally when GNSS is interfered with or has no signal. This tactical-grade IMU has relatively high accuracy compared to tactical-grade IMUs from other peer companies. If you want to purchase our IMU, please contact our relevant personnel.

website：https://www.ericcointernational.com/inertial-measurement-units

Email: info@ericcointernational.com

Whatsapp: 13992884879

Advantages of Fiber Optic North Seekers in Mining

The fiber optic gyro north seeker is an inertial product with a gyroscope as its core component. Fiber optic gyroscope is a kind of gyroscope with simple structure and easy to be mass-produced. Its development is based on low-loss optical fibers and small and reliable semiconductor light sources. It is an interferometer composed of optical fibers and is a static gyroscope. Its main advantages are: ① It uses solid-state devices, no moving parts, and the instrument is firm and stable. ②Long continuous working time. ③Long life, low power consumption, stable and reliable signal. It is precisely because of the advantages of fiber optic gyroscopes that are different from other traditional gyroscopes that many domestic and foreign research institutions attach great importance to the development of fiber optic gyroscope north seekers. Therefore, it has a broad application market and high research value.

Determining the north direction is an important parameter during the mining process and is also an important guarantee for the normal operation of the project. The underground conditions are complex and changeable, and magnetic field interference has a great impact on the project. The fiber optic gyro north seeker has strong anti-interference ability and a large measurement range, making it suitable for mining operations.

Ericco Company has a low-cost three-axis fiber optic north seeker, which is mainly used in mining. It not only uses a closed-loop fiber optic gyroscope as the core component, but is more suitable for customers with limited budgets. https://www.ericcointernational.com/north-finders/fiber-optic-gyro-north-finder/er-fiber-optic-gyro-north-finder-for-mining.html

If you are interested in fiber optic gyro north finder, you can discuss it with us.Contact information:

Web: https://www.ericcointernational.com/north-finders

Email: info@ericcointernational.com

Whatsapp: +8613992884879

Wechat: 13992884879