Gyroscopes and accelerometers help to precisely control the robot's movements

With the assistance of accelerometer

Precisely controlled movement

Accuracy

Only when a robot can master its position in space and the speed of movement can it ensure the accuracy of its moving position and perform the required actions. It needs to rely on gyroscopes and accelerometers to detect the angular rate and acceleration of movement. This article will introduce the development and characteristics of gyroscopes and accelerometers, as well as the characteristics of the highly integrated 6-DOF XYZ-axis gyroscope and XYZ-axis accelerometer launched by Murata.

Equipped with electric gyroscope and accelerometer

Gyroscopes and accelerometers are both used to measure the motion of an object. They are often used in many products, such as tablet computers, robots, etc.

The operating principle of a gyroscope is to use the gyroscopic effect, which is a physical phenomenon that when a rotating object is subjected to an external force, it will generate a torque that causes its rotation axis to change. In a gyroscope, a rotor is fixed on three axes. When the gyroscope is subjected to an external force, the rotor will be subjected to a torque, causing the gyroscope to rotate, so that the rotation state of the object can be measured.

The operating principle of an accelerometer is based on Newton's second law of motion, which states that when an object is subjected to an external force, it will experience acceleration. In an accelerometer, a mass is attached to a spring. When an external force is applied to the accelerometer, the mass is compressed or stretched by the spring, which allows the acceleration of the object to be measured. Typically, accelerometers are mounted on three axes to measure the acceleration of an object in three directions.

Gyroscopes and accelerometers are often combined to form a device called a six-axis sensor. A six-axis sensor can measure both the rotation and acceleration of an object and transmit the data to a computer or other device for further analysis and application.

In recent years, with the development of technology, gyroscopes and accelerometers have also made some new developments. First, the accuracy and stability of gyroscopes have been greatly improved. At present, some high-precision (micro-electromechanical system) gyroscopes have appeared on the market, which can achieve centimeter-level measurement accuracy and have high stability and anti-interference.

On the other hand, the application scope of gyroscopes and accelerometers is also expanding. In addition to traditional applications such as sports and mobile phone sensing, there are now many emerging applications, such as fitness, virtual reality, etc. In order to cope with these applications, the accuracy and sensitivity of gyroscopes and accelerometers are also further improved, and more functions and features are added, such as low power consumption, small size, multi-axis measurement, etc.

In general, with the development of science and technology, the application prospects of gyroscopes and accelerometers are becoming more and more broad, and technological innovation and upgrading will continue to meet more and higher-end application needs.

Choosing gyroscopes and accelerometers based on application requirements

There are many factors to consider when choosing a gyroscope and accelerometer. First of all, the application scenario must be considered. Different application scenarios require different gyroscopes and accelerometers, such as mobile phone sensing, drone control, etc. When choosing, you must choose the appropriate gyroscope and accelerometer based on the specific application requirements.

In addition, accuracy and stability are important performance indicators of gyroscopes and accelerometers, and products with different accuracy and stability are usually selected according to specific application requirements. Next, we need to consider sensitivity and range, which are important parameters of gyroscopes and accelerometers. The higher the sensitivity, the smaller the acceleration range that can be measured; the larger the range, the wider the acceleration range that can be measured. Therefore, it is necessary to select gyroscopes and accelerometers with different sensitivities and ranges according to specific application requirements.

On the other hand, choosing a reputable supplier can ensure the quality and service of the product. Of course, cost is also an important factor to consider when choosing gyroscopes and accelerometers, and you need to choose the right product according to your budget.

Choosing gyroscopes and accelerometers requires comprehensive consideration of multiple factors and choosing the right product based on specific application requirements. When choosing, you can refer to the product's technical specifications, performance evaluation, supplier and brand information for comprehensive comparison and evaluation.

Highly integrated 6-DOF gyroscope and accelerometer

Murata develops and manufactures gyroscope and accelerometer components based on the company's mature 3D MEMS technology and highly integrated devices. Murata's gyroscopes provide a level of performance that is usually only available for expensive module products. The sensor device and measurement circuit are assembled in a pre-molded plastic dual in-line (DIL) package, protected with silicone and covered with a stainless steel lid. The products are RoHS-compliant and suitable for lead-free reflow soldering.

The gyroscope sensor launched by Murata can be applied to robot motion sensing detection. This SCHA63T is a 6-DOF XYZ-axis gyroscope and XYZ-axis accelerometer suitable for industrial applications. This single-package 6-DOF component can achieve an orthogonality error better than 0.14° after cross-axis calibration. The gyroscope bias instability is as low as 1°/h, and the gyroscope noise density level reaches 0.0015°/s/√Hz. It has stable offset and sensitivity over the entire temperature range, and has outstanding linearity and vibration performance. It has extensive self-diagnostic functions, as well as an angular rate measurement range of ±300°/s and an acceleration measurement range of ±6g. It can operate in a temperature range of −40℃ to +110℃, supports 3.0V to 3.6V voltage, and is a 32-pin rugged SO shell component that complies with RoHS standards. The size is 19.71 mm × 12.15 mm × 4.6 mm (length × width × height), and can be used in safety-critical applications.

The SCHA63T sensor is the first single-package 6-DoF part to offer this level of performance, which was previously only available in expensive, high-end inertial measurement unit (IMU) modules. The sensor enables centimeter-level accuracy in machine dynamics and position sensing in harsh environments and helps ensure reliable, robust and validated designs.

SCHA63T is suitable for applications requiring high performance and harsh environmental requirements. Typical applications include inertial measurement units (IMU), navigation and positioning, machine control and guidance, dynamic inclination, robot control and UAV products.

Combined high performance 3-axis angular rate sensor

and 3-axis accelerometer

The SCHA63T series includes two products - SCHA63T-K01 and SCHA63T-K03. Both SCHA63T-K01 and SCHA63T-K03 are combined high-performance 3-axis angular rate sensors and 3-axis accelerometers. It consists of X, Y and Z-axis angular rate sensors and an integrated 3-axis accelerometer based on Murata's mature 3D-MEMS technology. Processing is done through two mixed signals, and these ASICs provide angular rates through flexible SPI digital. The sensor components and ASICs are packaged in a pre-molded SOIC 32 plastic housing to ensure reliable operation throughout the product's life cycle.

The SCHA63T-K01 and SCHA63T-K03 are designed, manufactured and tested to meet high stability, reliability and quality requirements. The parts have very stable outputs within the temperature, humidity and vibration ranges, and have a variety of advanced self-diagnostic functions. They are suitable for SMD mounting and comply with RoHS and ELV specifications.

In terms of gyroscope specifications, the maximum range of SCHA63T-K01 is (XYZ) ±125°/s, and that of SCHA63T-K03 is (XYZ) ±300°/s. The amplitude response of both models is 13, 20, 46 or 300Hz, and the offset temperature dependence is (Z) ±0.085°/s, (XY) ±0.65°/s. The sensitivity of SCHA63T-K01 is (Z) 160 LSB/°/s, (XY) 160 LSB/°/s, and that of SCHA63T-K03 is (Z) 80 LSB/°/s, (XY) 80 LSB/°/s. Both products support digital/SPI output types.

The SCHA63T-K01 and SCHA63T-K03 have the same specifications for the accelerometer, with a maximum range of ±6g, an amplitude response of 13, 20, 46 or 300Hz, an offset temperature dependence of (XYZ) ±7.3mg, a sensitivity of 4905 LSB/g, and an output type of digital/SPI.

Conclusion

Gyroscopes and accelerometers are key components for robot applications and have a significant impact on the accuracy of robot movement. The highly integrated 6-DOF XYZ-axis gyroscope and XYZ-axis accelerometer launched by Murata using 3D MEMS technology can meet the requirements of robot applications in terms of accuracy, volume, and temperature range, and will be an ideal choice for robot applications.

Review editor: Liu Qing