Investigation of Acoustic Injection on the MPU6050 Accelerometer

Abstract

Acoustic injection is one of the most dangerous ways of causing micro-electro–mechanical systems (MEMS) failures. In this paper, the failure mechanism of acoustic injection on the microprocessor unit 6050 (MPU6050) accelerometer is investigated by both experiment and simulation. A testing system was built to analyze the performance of the MPU6050 accelerometer under acoustic injection. A MEMS disassembly method was adopted and a MATLAB program was developed to establish the geometric model of MPU6050. Subsequently, a finite element model of MPU6050 was established. Then, the acoustic impacts on the sensor layer of MPU6050 were studied by acoustic–solid coupling simulations. The effects of sound frequencies, pressures and directions were analyzed. Simulation results are well agreed with the experiments which indicate that MPU6050 is most likely to fail under the sounds of 11,566 Hz. The failure mechanism of MPU6050 under acoustic injection is the relative shift of the capacitor flats caused by acoustic–solid resonance that make the sensor detect false signal and output error data. The stress is focused on the center linkage. MPU6050 can be reliable when the sound pressure is lower than 100 dB.

Theoretical and Experimental Study on Nonlinear Failure of an MEMS Accelerometer under Dual Frequency Acoustic Interference

“…Compared to a single frequency acoustic attack, the maximum offset of the output error acceleration (∆ a b ) was 4.4 m/s 2 and the maximum fluctuation amplitude (∆ a f ) was 4.97 m/s 2 . In the experimental results of the existing single frequency attack accelerometer, the maximum offset of the single frequency acoustic interference was 1.27 m/s 2 without amplitude fluctuation [ 17 ]. Firstly, the interference amplitude of the dual frequency attack greatly improved.…”

“…The acceleration of the amplitude fluctuation caused by the AC signal was recorded as Δa f = 2.6 m/s 2 . There was no generation for the acceleration of the amplitude fluctuation in previous research [ 17 ].…”

“…The maximum value was 4.4 m/s 2 . The previous acoustic injection attack accelerometer experiment resulted in an offset of 1.27 m/s 2 [ 17 ]. We achieved 3.46 times the previous result.…”

“…The main cause of ultrasonic shock is the disharmony between the gyroscope’s sensitive axis and driving axis [ 16 ]. In 2019, the Hui Li scientific research team of Wuhan University verified the influence of acoustic interference on a MEMS accelerometer through ANSYS multiphysical field simulation [ 17 ].…”

Investigation of Potting-Adhesive-Induced Thermal Stress in MEMS Pressure Sensor

“…It showed worse accuracy when the sensors were heated. Zhang et al [ 12 ] studied the output error of inertial measurement unit caused by acoustic injection. Tran et al [ 13 ] investigated the effect of temperature on the output of a piezoresistive sensor and concluded that the thermal performance instability is mainly attributable to the effects of temperature, the residual stress due to fabrication and the residual stress due to packaging.…”