Dataset Information

Effect of IMU Design on IMU-Derived Stride Metrics for Running.

ABSTRACT: Researchers employ foot-mounted inertial measurement units (IMUs) to estimate the three-dimensional trajectory of the feet as well as a rich array of gait parameters. However, the accuracy of those estimates depends critically on the limitations of the accelerometers and angular velocity gyros embedded in the IMU design. In this study, we reveal the effects of accelerometer range, gyro range, and sampling frequency on gait parameters (e.g., distance traveled, stride length, and stride angle) estimated using the zero-velocity update (ZUPT) method. The novelty and contribution of this work are that it: (1) quantifies these effects at mean speeds commensurate with competitive distance running (up to 6.4 m/s); (2) identifies the root causes of inaccurate foot trajectory estimates obtained from the ZUPT method; and (3) offers important engineering recommendations for selecting accurate IMUs for studying human running. The results demonstrate that the accuracy of the estimated gait parameters generally degrades with increased mean running speed and with decreased accelerometer range, gyro range, and sampling frequency. In particular, the saturation of the accelerometer and/or gyro induced during running for some IMU designs may render those designs highly inaccurate for estimating gait parameters.

SUBMITTER: Potter MV

PROVIDER: S-EPMC6603669 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Effect of IMU Design on IMU-Derived Stride Metrics for Running.

Potter Michael V MV Ojeda Lauro V LV Perkins Noel C NC Cain Stephen M SM

Sensors (Basel, Switzerland) 20190607 11

Researchers employ foot-mounted inertial measurement units (IMUs) to estimate the three-dimensional trajectory of the feet as well as a rich array of gait parameters. However, the accuracy of those estimates depends critically on the limitations of the accelerometers and angular velocity gyros embedded in the IMU design. In this study, we reveal the effects of accelerometer range, gyro range, and sampling frequency on gait parameters (e.g., distance traveled, stride length, and stride angle) est ...[more]

PMID: 31181688

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Dataset Information

Effect of IMU Design on IMU-Derived Stride Metrics for Running.

Publications

Effect of IMU Design on IMU-Derived Stride Metrics for Running.

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