MEMS Inertial sensor: IMU measures angular velocity and acceleration

KJ3002X1-BF1 MEMS accelerometers are used to measure the linear acceleration of objects, and capacitive MEMS accelerometers currently dominate the market. MEMS accelerometer is a device that can measure the linear acceleration of an object. It is usually composed of mass block, damper, elastic element, sensitive element and adaptive circuit. The measurement principle is as follows: In the process of acceleration, the acceleration value can be calculated by measuring the inertial force of the mass block. When the initial velocity is known, the linear velocity can be obtained by integrating the acceleration with time, and the linear displacement can be calculated by integrating the linear velocity with time. According to the sensing principle, MEMS accelerometers can be divided into piezoresistive, capacitive and thermal types, among which capacitive MEMS accelerometers have high sensitivity, high precision and low temperature sensitivity, and currently occupy a dominant position in the market.

KJ3002X1-BF1 MEMS gyroscope uses Coriolis effect to measure angular rate, which is mainly used in navigation, attitude perception, platform stability and other applications. The core of the MEMS gyroscope is a micromechanical (MEMS) chip, a special control circuit (ASIC) chip and stress isolation package, and the Coriolis effect is its basic working principle: The movable mass block oscillates at high speed under the control of the drive circuit. When the object rotates, the mass block has a transverse displacement perpendicular to the direction of oscillation. The transverse displacement is proportional to the input angular rate, so the diagonal velocity rate can be measured by measuring the transverse displacement.

KJ3002X1-BF1 The IMU is composed of accelerometer and gyroscope, which can measure the angular rate and acceleration speed of the object in three-dimensional space, and help the pedestrian robot to achieve attitude control and balance maintenance. An IMU usually contains three axial gyroscopes and three axial accelerometers, which can measure the angular rate and acceleration of the object in the three-dimensional space. IMU is a key sensor for humanoid robot to maintain balance and motion control, which can help humanoid robot to achieve attitude control, balance maintenance, navigation and positioning. Attitude control and balance maintenance: The inertial stability control system continuously monitors the attitude and position changes of the system, and uses the control algorithm to control the servo structure, so as to dynamically adjust the attitude of the system to achieve the goal of maintaining a stable attitude and balance.

KJ3002X1-BF1

Navigation and positioning: By integrating diagonal speed and linear acceleration according to time and superposition, humanoid robots can dynamically determine their own position changes, and because they do not need external information, they can avoid being affected by external interference.

KJ3002X1-BF1 The global MEMS inertial sensor market is expected to continue to grow, and IMUs are gradually replacing standalone MEMS gyroscopes. MEMS inertial sensor is a device that converts the acceleration, position and attitude of an object into an electrical signal, including MEMS accelerometer, MEMS gyroscope, magnetometer and inertial measurement unit (IMU). According to Yole Intelligence data, in terms of the overall market size, the global MEMS inertial sensor market size has grown from $2.831 billion in 2018 to $3.509 billion in 2021. The market size is expected to reach $4.944 billion by 2027, with a CAGR of 6.39% from 2018 to 2027; In terms of the product structure of the market, the market for MEMS accelerometers, magnetometers and IMUs continues to grow, while the market for MEMS gyroscopes is shrinking year by year, mainly due to the gradual replacement of independent MEMS gyroscopes by IMUs in high-end consumer electronics and automotive electronics markets.

The MEMS inertial sensor market is dominated by international manufacturers, and the market concentration is high. According to Yole Intelligence data, in the MEMS accelerometer market, Bosch, ST, MURATA, NXP, ADI are the top five manufacturers, with a CR5 market share of 84%; In the MEMS gyroscope market, TDK, ADI, HONEYWELL, Bosch and ST are the top five manufacturers, with a CR5 market share of 83%. In the IMU market, Bosch, ST, TDK, HONEYWELL and ADI are the top five manufacturers, with a CR5 market share of 88%. The domestic MEMS inertial sensor industry started late, and the overall sales scale of domestic enterprises still has a large gap compared with foreign leading enterprises, so the main market share of the MEMS inertial sensor market is still occupied by international manufacturers.