title: Gait posture estimation using wearable acceleration and gyro sensors.
abstract: A method for gait analysis using wearable acceleration sensors and gyro sensors is proposed in this work. The volunteers wore sensor units that included a tri-axis acceleration sensor and three single axis gyro sensors. The angular velocity data measured by the gyro sensors were used to estimate the translational acceleration in the gait analysis. The translational acceleration was then subtracted from the acceleration sensor measurements to obtain the gravitational acceleration, giving the orientation of the lower limb segments. Segment orientation along with body measurements were used to obtain the positions of hip, knee, and ankle joints to create stick figure models of the volunteers. This method can measure the three-dimensional positions of joint centers of the hip, knee, and ankle during movement. Experiments were carried out on the normal gait of three healthy volunteers. As a result, the flexion-extension (F-E) and the adduction-abduction (A-A) joint angles of the hips and the flexion-extension (F-E) joint angles of the knees were calculated and compared with a camera motion capture system. The correlation coefficients were above 0.88 for the hip F-E, higher than 0.72 for the hip A-A, better than 0.92 for the knee F-E. A moving stick figure model of each volunteer was created to visually confirm the walking posture. Further, the knee and ankle joint trajectories in the horizontal plane showed that the left and right legs were bilaterally symmetric.
authors.affiliation: Division of Human Mechanical Systems and Design, Graduate School of Engineering, Hokkaido University, N13 W8, Kita-ku, Sapporo 060-8628, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Takeda
authors.forename: Shigeru
authors.initials: S
authors.lastname: Tadano
authors.forename: Akiko
authors.initials: A
authors.lastname: Natorigawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Todoh
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yoshinari
mesh_terms: D000054:Acceleration; D000328:Adult; D003198:Computer Simulation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D011187:Posture / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers