Influence of Acoustic Noise on the Dynamic Performance of MEMS Gyroscopes

Advances in MEMS technology have resulted in relatively low cost gyroscopes and accelerometers and, correspondingly, inexpensive inertial measurement systems. This has opened up the field of applications for inertial measurement units (IMUs) and they are currently being proposed for use in a wide variety of possible applications, with environmental conditions ranging from mild to harsh. Of particular interest in this study are MEMS gyroscopes, which are based upon vibratory, rather than rotational, designs and are especially susceptible to the effects of acoustic noise, as compared to conventional gyroscopes. This is particularly true for certain applications. For example, in some aerospace environments, noise levels can be greater than 120 dB and extend over a frequency range greater than 20 kHz. Output signals can be overwhelmed by such effects, becoming extremely contaminated and noisy and, can even be completely saturated. So, it is important to develop an understanding of the influence of high levels of noise on MEMS gyroscope performance and to develop methodologies to mitigate such effects. In the present investigation, a series of experimental studies were conducted for a variety of MEMS gyroscope designs. Each unit was exposed to a range of acoustic noise amplitudes and frequencies. The output signals were recorded and analyzed. The results are presented and discussed in detail. Strategies for mitigating such effects were identified and tested. Those results are also discussed in detailed.

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MEMS Gyroscopes Susceptibility to High Frequency Acoustic Noise

Volume 1: 22nd Biennial Conference on Mechanical Vibration and Noise, Parts A and B ◽

10.1115/detc2009-87854 ◽

2009 ◽

Author(s):

Grant Roth ◽

George T. Flowers ◽

Robert Dean

Keyword(s):

High Frequency ◽

Detrimental Effect ◽

Acoustic Noise ◽

Harsh Environments ◽

Sound Power ◽

High Frequencies ◽

Inertial Measurement ◽

Mems Gyroscopes ◽

Measurement Units ◽

Mitigation Techniques

MEMS gyroscopes are becoming more prevalent in inexpensive inertial measurement units used in a variety of harsh environments. It has been shown in previous studies that high power high frequency acoustic noise can have a detrimental effect on these devices. This study examines the threshold of the sound power levels required at these high frequencies to generate detrimental effects on the output of MEMS gyroscopes. This study provides basic background work for further research into mitigation techniques for higher powered high frequency acoustic noise.

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Mems Technology Quality Requirements as Applied to Multibeam Echosounder

Polish Maritime Research ◽

10.2478/pomr-2018-0132 ◽

2018 ◽

Vol 25 (4) ◽

pp. 59-64

Author(s):

Krzysztof Bikonis ◽

Jerzy Demkowicz

Keyword(s):

Inertial Sensors ◽

Low Cost ◽

Microelectromechanical System ◽

Power Efficient ◽

Inertial Measurement ◽

Multibeam Echosounder ◽

Mems Technology ◽

Measurement Units ◽

And Performance

Abstract Small, lightweight, power-efficient and low-cost microelectromechanical system (MEMS) inertial sensors and microcontrollers available in the market today help reduce the instability of Multibeam Sonars. Current MEMS inertial measurement units (IMUs) come in many shapes, sizes, and costs - depending on the application and performance required. Although MEMS inertial sensors offer affordable and appropriately scaled units, they are not currently capable of meeting all requirements for accurate and precise attitudes, due to their inherent measurement noise. The article presents the comparison of different MEMS technologies and their parameters regarding to the main application, namely Multibeam Echo Sounders (MBES). The quality of MEMS parameters is crucial for further MBES record-processing. The article presents the results of undertaken researches in that area, and these results are relatively positive for low-cost MEMS. The paper undertakes some vital aspect of using MEMS in the attitude and heading reference system (AHRS) context. The article presents a few aspects of MEMS gyro errors and their estimation process in the context of INS processing flow, as well as points out the main difficulties behind the INS when using a few top MEMS technologies.

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Testing of the Possibilities of Using IMUs with Different Types of Movements

Geoinformatics FCE CTU ◽

10.14311/gi.12.10 ◽

2014 ◽

Vol 12 ◽

pp. 61-66 ◽

Cited By ~ 2

Author(s):

Pavol Kajánek

Keyword(s):

Inertial Navigation System ◽

Low Cost ◽

Indoor Navigation ◽

Integrated System ◽

Test Results ◽

Inertial Measurement Units ◽

Inertial Measurement ◽

Improve Accuracy ◽

Different Types ◽

Measurement Units

Inertial navigation system (INS) is a self-contained navigation technique. Its main purpose is to determinate the position and the trajectory of the object´s movement in space. This technique is well represented not only as a supplementary method (GPS/INS integrated system) but as an autonomous system for navigation of vehicles and pedestrians, also. The aim of this paper is to design a test for low-cost inertial measurement units. The test results give us information about accuracy, which determine the possible use in indoor navigation or other applications. There are described some methods for processing the data obtained by inertial measurement units, which remove noise and improve accuracy of position and orientation.

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POF-IMU sensor system: A fusion between inertial measurement units and POF sensors for low-cost and highly reliable systems

Optical Fiber Technology ◽

10.1016/j.yofte.2018.04.012 ◽

2018 ◽

Vol 43 ◽

pp. 82-89 ◽

Cited By ~ 4

Author(s):

Arnaldo G. Leal-Junior ◽

Laura Vargas-Valencia ◽

Wilian M. dos Santos ◽

Felipe B.A. Schneider ◽

Adriano A.G. Siqueira ◽

...

Keyword(s):

Low Cost ◽

Sensor System ◽

Inertial Measurement Units ◽

Inertial Measurement ◽

System A ◽

Reliable Systems ◽

Measurement Units

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On Using Inertial Measurement Units for Solving the Direct Kinematics Problem of Parallel Mechanisms

Robotics ◽

10.3390/robotics8040099 ◽

2019 ◽

Vol 8 (4) ◽

pp. 99

Author(s):

Stefan Schulz

Keyword(s):

Low Cost ◽

Parallel Mechanisms ◽

Inertial Measurement Units ◽

Inertial Measurement ◽

Sensor Structure ◽

Prismatic Joints ◽

Measurement Units ◽

Linear Actuators ◽

Achievable Accuracy ◽

Direct Kinematics

In this paper, we investigate the accuracy and the computational efficiency of an IMU-based approach for solving the direct kinematics problem of parallel mechanisms with length-variable linear actuators under dynamic conditions. By avoiding to measure the linear actuators’ lengths and by using orientations instead, a comprehensive, low-cost sensor structure can be obtained that provides a unique solution for the direct kinematics problem. As a representative example, we apply our approach to the planar 3-RPR parallel mechanism, where P denotes active prismatic joints and R denotes passive revolute joints, and investigate the achievable accuracy and robustness on a specially designed experimental device. In this context, we also investigate the effect of sensor fusion on the achievable accuracy and compare our results with those obtained from linear actuators’ lengths when the Newton-Raphson algorithm is used to compute the manipulator platform’s pose iteratively. Finally, we discuss the applicability of inertial measurement units (IMUs) for solving the direct kinematics problem of parallel mechanisms.

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Technology in Rehabilitation: Evaluating the Single Leg Squat Exercise with Wearable Inertial Measurement Units

Methods of Information in Medicine ◽

10.3414/me16-02-0002 ◽

2017 ◽

Vol 56 (02) ◽

pp. 88-94 ◽

Cited By ~ 24

Author(s):

Tomás E. Ward ◽

Eamonn Delahunt ◽

Brian Caulfield ◽

Darragh F. Whelan ◽

Martin A. O'Reilly

Keyword(s):

Lumbar Spine ◽

Lower Limb ◽

Low Cost ◽

Objective Evaluation ◽

Inertial Measurement Units ◽

Lower Limb Injury ◽

Inertial Measurement ◽

Increased Risk ◽

Measurement Units ◽

Single Leg Squat

SummaryBackground: The single leg squat (SLS) is a common lower limb rehabilitation exercise. It is also frequently used as an evaluative exercise to screen for an increased risk of lower limb injury. To date athlete/patient SLS technique has been assessed using expensive laboratory equipment or subjective clinical judgement; both of which are not without shortcomings. Inertial measurement units (IMUs) may offer a low cost solution for the objective evaluation of athlete/patient SLS technique.Objectives: The aims of this study were to determine if in combination or in isolation IMUs positioned on the lumbar spine, thigh and shank are capable of: (a) distinguishing between acceptable and aberrant SLS technique; (b) identifying specific deviations from acceptable SLS technique.Methods: Eighty-three healthy volunteers participated (60 males, 23 females, age: 24.68 +/− 4.91 years, height: 1.75 +/− 0.09 m, body mass: 76.01 +/− 13.29 kg). All participants performed 10 SLSs on their left leg. IMUs were positioned on participants’ lumbar spine, left shank and left thigh. These were utilized to record tri-axial accelerometer, gyroscope and magnetometer data during all repetitions of the SLS. SLS technique was labelled by a Chartered Physiotherapist using an evaluation framework. Features were extracted from the labelled sensor data. These features were used to train and evaluate a variety of random-forests classifiers that assessed SLS technique.Results: A three IMU system was moderately successful in detecting the overall quality of SLS performance (77% accuracy, 77% sensitivity and 78% specificity). A single IMU worn on the shank can complete the same analysis with 76% accuracy, 75% sensitivity and 76% specificity. Single sensors also produce competitive classification scores relative to multi-sensor systems in identifying specific deviations from acceptable SLS technique.Conclusions: A single IMU positioned on the shank can differentiate between acceptable and aberrant SLS technique with moderate levels of accuracy. It can also capably identify specific deviations from optimal SLS performance. IMUs may offer a low cost solution for the objective evaluation of SLS performance. Additionally, the classifiers described may provide useful input to an exercise biofeed-back application.

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