Assessing the Impact of IMU Sensor Location on Spatio-Temporal Gait Parameter Estimation.

Gait analysis is essential for understanding human locomotion patterns and diagnosing gait disorders. While traditional methods typically rely on complex equipment and laboratory settings, recent advances in technology have enabled gait analysis outside of controlled laboratory settings. This study explores the impact of sensor placement on the accuracy of gait parameter estimation using inertial measurement units (IMUs). We conducted experiments involving 31 healthy participants walking under controlled conditions while wearing multiple IMU sensors at different locations on their bodies, including three locations to simulate commercially available wearable devices - earphones, watches, and smartphones. In addition, participants wore a robotic hip exoskeleton to test an IMU sensor and joint angle sensors in it. The Combination of sensors in the exoskeleton was found to be the best when averaged for four gait parameters: speed, stride length, step length, and gait phase; and for each gait parameter, the best sensor location was all different. These findings have important implications for the design of wearable devices for gait analysis and rehabilitation applications, as well as for clinical practice and sports medicine.